lbw6303: Have you got to the bottom or your engine issue?
Did you go with FASS-TS or AirDog-II-4G?
And you asked about the digital fuel pressure gauge I mounted in my dash. So here are some other Amazon links about the type of fuel gauge I installed just under my dash.
Note: These aftermarket gauges have brighter colored displays than my Freightliner dash... and while I tapped into the instrument panel (dim-able) light it still is brighter... so IMO you don't want to mount this gauge up higher.
Note: I think the digital gauge is nice, but it's another $130 and 3 more hours of time to install. And after you look at this gauge for the first 1,000 miles it will not be as exciting... and you may wish you just installed an oil filled fuel pressure gauge on top of your #3 filter for $25.
In my coach, I like looking from the top-down to read the oil filled fuel pressure gauge, because my fuel filters are remote mounted in my Freightliner engine bay and not on the side like Spartan chassis owners use.
Therefore, you Spartan and Roadmaster chassis owners many want to go with a side-view gauge. Just make sure you get the right adapter because most side-view pressure gauges have larger faces and use 1/4" NPT and the only adapter I found is for an 1/8" NPT to 10mm (27 thread). This also means you need clearance on top!
** Also, the smaller 1-1/2" gauge face types use a 1/8" NPT thread. However, the 10mm thread is not tapered so you need to buy a neophreme o-ring separate at any ACE Hardware store. (HD & Lowe's don't carry it.)
=== ~ ===
...But if you go with the digital GlowShift gauge, this kit will come with a M10 x 1.0 Male to 1/8-27 NPT Female Gauge Sensor Sender (with tapered thread) which you can screw into the top of your #3 Filter (if there is a port there) or you can use the FASS or AirDog 1/8" NPT port.
=== Other parts that may work better ===
This gauge below is a 1/4" NPT - Side view - Oil Filled pressure gauge. Also notice it only displays + fuel pressure.
* You can also order 100' of 3/8" split-plastic loom pm Amazon for your gauge wires; and you will need 15'-25' of 1' to 1-1/8" for your fuel lines where it gets hot around your engine. Get the high heat type at Walmart or your auto parts store.
**** I still don't have any information about AirDog-II-4G pumps being better than FASS, but it's coming. Another owner is in the process of installing an AirDog pump now so I'm waiting on his feed back. Stay tuned!
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Imnprsd,
As always very helpful info. Thanks. Will be ordering a 165 GPH FASS system soon and will be doing a dash gauge as well. I assume all fittings and hoses on the coach are metric (2001 HR Endeavor on a Roadmaster) so if I use my existing lines to and from tank not yet sure how all interfaces. It'll all get figured out in due course.
I assume we have not heard what the OP root cause was. I will be interested in know where that 115 psi was coming from. Also looking forward to hearing more on the AirDog install. Take care.
Thanks for checking in on my progress. Here's a status update:
RE the 3 stalls on my trip to Fla from Mn in Oct 2019. All of which looked like contaminated fuel/bad filters, but now don't seem to fit that diagnosis.
1) I went to an RV show in Tampa in Jan 2020. Cummins and Freightliner reps. see no problem with continuing t o 'Suck Fuel" over several feet by CAPS pump.
I sense something else going on that they don't want to talk much about.
2) I've been to the Cummins facility in Tampa for discussions. I plan to take my coach there this week 3/9/20. Will report findings when I know more.
Input from their Mechanic was that I likely have a "restriction" somewhere btwn the fuel tank and primary filter causing/allowing air to be sucked into the primary filter somehow/somewhere, thus causing the lean air/fuel mix in the CAPS and somehow causing the stall.
No comment on what is actually triggering/doing the Shutdown and subsequent "healing" that allows the unit to start up a few hours later and run normally, nor why I see no Codes set. No one seems to want to venture an answer to that question for me. I'll just have to wait for them to do a diagnosis.
3) I anticipate abandoning the fuel supply line and letting them run a new one just to rule out the fuel supply line.
4) I've determined that my Tank vent line is clear and open -- No mud daubers plugging it up. There is still a possibility that a "restriction" could be in the "inside-the-tank" pick up tube from a buildup of sludge in the tank -- All tbd. Not sure what that fix looks like or entails.
5) I'm still not ruling out the ECM, but expect them to check it out thoroughly.
6) There's NO question in my mind that Air is getting in somewhere prior to the primary filter. I don't think it's in the lift pump, but my pump is apparently older and doesn't even look like the ones others have posted, so the supply line theory is plausible to me.
7) I hope to report on my "Cummins experience" in a few days.
8) Beyond that, I've found a local FAS installer that I think has the experience to install that system once I get through the Cummins shop. His suggestion -- Let Cummins replace the supply line no matter what. He will tap into that as close as he can to the tank so he "Pushes" fuel most of the way. Not exactly sure where he will mount the FAS unit, but it will be near the fuel tank. Not resolved yet with him, is how where to locate the filters. my sense is that he should just install the pump and use the rest of the existing infrastructure, including the lift pump so that I can "fail soft" if the FAS pump fails and revert back to the original CAPS/Lift Pump design in order to keep moving, or get to a repair facility.
9) I still can't explain why the pressure guage that I installed on my Secondary filter is reading 110 lbs of pressure. Hoping Cummins can either fix that or declare it "normal".
10) Still no measure of Vacuum pressure on the primary filter side.
11) My FAS installer knows that I want Gauges in my cockpit for vacuum, fuel pressure, or both and says it's straight forward to do. I still plan to add that feature.
More to come later. This Forum has been a HUGE help.
lbw6303.
I have read that some owners end up running a new fuel line when all else cannot be explained. ...And that did the trick. However, these posts are on coaches older than 2002.
Apparently, the rubber used prior to 2002 was different. But after 2003 I have not read about any hose issues. And believe me, when I was having all these fuel delivery issues, I thought about replacing my fuel-in hose, because that is all the experts had left to look at. And those SOBs didn't even tell me about how I should first try tightening my 3-lift pump bolts, which fortunately for me turned out to fix my fuel delivery issue. But by then I was so "rattled" I decide to install the FASS-TS pump and I am very glad I did.
I also understand that while an old fuel line will let air to get sucked-in... this same old fuel like will NOT let fuel leak out! Therefore, it would appear you can install a FASS-TS or AirDog-II-4G pump without worry over changing your old fuel line. (TBD)
That said, I will also say it's a misnomer that you need to install either of these 12v pumps near your fuel tank. In fact, these pumps can be placed anywhere so long as they are not more than 3 feet above the sump in the tank. And I personally would prefer not to mount a fuel filter under the coach, because I want easy access to it.
The "old school" mechanics will tell you have to (or should) mount the pump near the fuel tank, but that is incorrect.
I think I would spend the money on a new FASS or AirDog first, but clearly you have much smarter people at Cummins working on your problem.
Just one thing: If they are so smart, then why don't they know more about the benefits of a FASS or AirDog pump? ...Or maybe they do, but their "Cummins Culture" has them tongue-tied!
Personally, I think Cummins has always known about this problem. But they sell engines.
It's the coach manufactures who put Cummins engines in diesel pushers. So who is responsible for ensuring proper fuel delivery?
...The owner of the RV that's who. Otherwise, I would have organized a "Class Action." Not to mention it takes 50,000+ miles before these type of fuel delivery problems start to happen. So again, IMO, each RV owner needs to decide "when" they upgrade to a FASS or AirDog 12V pump... and not "if" they should.
I promised to report progress in resolving my "stall issues". It's been several weeks of not enough progress, so here's where I am. In a nut shell, i stalled 3 times on a trip from MN to fl last October with my 2004 Monaco ISC 8.3 Cummins. I Believe I will need to install FASS system B4 I can have confidence in the reliability of my unit, but first I want the Cummins people to do their evaluation I finally got the rig over to Cummins Tampa about 4 weeks ago. Their backlog is high this time of year and exacerbated by COVID19. I'm relying on their forensics skills to sleuthe out what really happened:
1) first look was --- "You don't have a CAPS Pump!" Mine is a "High Pressure Common rail" type pump. likewise, it's a different/older style lift pump as well;
2) This explains the 110 PSI reading at secondary filter that everybody on the forum thought was too high. Apparently it's correct and maybe even too low;
3) The tests they've run so far has them thinking more in terms of an electrical issue than a fuel related one. I'm reminding them that I know for certain that The 2nd stall showed air in the primary filter suggesting that I was actually out of fuel -- wasn't! and that air was somehow getting into the fuel supply chain.
4) They know that I've verified that the fuel tank vent is NOT plugged at all;
5) I know that there is a lot of "clickety click" happening when I turn on the ignition switch suggesting that there are relays being armed/energized for things like the lift pump, the ECM and the glow plugs. So I'm prepared to believe that It could be an electrical component that has failed. up to and including the ignition switch and/or the ECM. although I seriously doubt it's the switch. Beyond that, I'm so skeptical of the suction fuel delivery design in these rigs that I still plan to install the FASS, but I don't want that to mask any other issues. I'll wait for Cummins recommendations.
6) I wish I could provide better, more conclusive status, but that's what I have for now. Cummins has cleared the decks a bit and should be able to put more time on it this week. more to come and once again, thanks to all on this forum for the great help you've provided. lbw6303.
Hi Everyone: it’s been several weeks since I updated this thread as I promised to do. My 2004 Monaco has been in the Cummins shop in Tampa for almost 2 months. In a nutshell, they can’t find anything wrong!!! even though they acknowledge that the stalls (3 of them) aren’t my imagination. I’ll try to be as brief as I can, but will also try to be “complete” with a brief history summary :
1) The “general case” --- Stall happens;
2) Immediately try to restart – Engine cranks, lift pump runs, but engine doesn’t “light up”;
3) Several hours later, it pops right off and runs fine for several hours. Not even a burp or a hiccup;
4) That surely sounds/acts like an overheated electronics that just needs to cool off a while
5) (OR some sort of “vapor lock” as though I’m out of fuel?).
6) After the first stall (south of Birmingham), cool down and new filters. – Popped right off and drove about 60 miles to Montgomery uneventfully;
7) Next day drove several hours, about 300 miles lots of hills in Al & Fl. Just cruising thru Perry, Fl at 30mph. no warning or symptoms --- (2nd) stall. Won’t start, but engine turns over as normal. Believe that we had no Injection pump output, but don’t know. Do know that lift pump was operating and the primary filter had air in it. Mobile mech thought I’d run out of fuel;
8) Next day (after new filters again), overnight in a parking lot. Cranks up runs fine, we drove almost 200 miles to Tarpon Springs Florida. Stalls in stop and go traffic. Same start up attempts. No joy. Towed into parking lot;
9) (By now I’m suspicious of something other than bad fuel) Next day cranks right up and drove about 6 miles to storage unit;
10) Cranked and ran several times while in storage (several months) – never a hiccup.
11) (March 2020) Drove 30+ miles from Palm Harbor to Cummins, towing my Truck on Hillsborough Ave across Tampa. No problems.
12) ECM??
13) Thermal sensor in Pump from running too lean, thus the pump heats up and ECM shuts it down?
14) I still believe I have air getting into the fuel system causing the pump to run too lean, resulting in some sluggish behavior. The only stall that showed sluggish was the FIRST one south of Birmingham, where it started to run sluggish before it just stopped. The other two times, it just “QUIT” w/o warning. But if the stalls are related to Chassis battery and related electrical, Why does it turnover as normal , but not actually start, as though the Injector pump isn’t working, or there’s some sort of Vapor lock?
15) No codes ever set. A CEL only just as the first stall happened. Went away when it cranked the next day.
16) I plan to have a FASS system installed no matter what, just to mitigate, or remove the issue of air getting sucked into the fuel delivery system, that may be all I need to do, but I’m not convinced that it is the only solution needed. I still suspect electronics somewhere.
17) This summary back to Cummins was after they tried to declare victory based on finding and replacing a defective Chassis battery cutoff switch. I told them I’d get back to them.
18) Final point in this introduction summary --- I found out that I DON’T have a CAPS pump!! Those were replaced on rigs like mine in about 2003 (My Monaco is a 2004 With Cummins ISC 8.3 330/350) in favor of a High Pressure Common Rail (HPCR) system and a different injector pump design (lift pump too I think). That explains why everyone helping on this thread expected me to report about 20 PSI after I installed a pressure gage and I was getting about 120PSI.
Good morning (Cummins)l:
I’ve thought a lot about my situation this weekend. You need a decision and I need to make one. I will address it all in two parts”
1) Fuel system;
2) Electrical systems;
1) Fuel system – You indicate that you’re not able to find anything wrong. I accept that. I’ve done extensive reading and interacting on the “forums” and find that there is a plethora of examples of what I think is wrong with my coach WRT fuel system and delivery. I see no point in chasing this any further. I intend to eliminate what I believe to be the underlying root cause of “Air getting into the fuel supply” (and causing my pump to run under-lubricated and to overheat) , by having someone install a FASS system, because with such a system, wherever air is getting in, should also have fuel leaking out where it can be detected.
The FASS fix will include eliminating/abandoning the supply line that comes from Tank to Primary filter (just in case there’s resistance there caused by deterioration caused by “ULSD” and/or debris getting into or beyond the filters to the injector pump. Unless the installer prefers a different method, I would retain everything from that point all the way to the Injector pump – Existing filters, Lift pump. Fuel tank return/recirculation lines. I also plan to have him install a Fuel pressure gauge that I can monitor from the cockpit.
I see no need to replace the Injector pump at this time, but I would like data from your testing indicating the Pressure readings you saw (and/or the range of those pressures). If your Tech’s think I should consider changing it, I’ll surely listen and discuss. Like-wise I see no need to change/replace the lift pump- two reasons, 1) I may bypass it altogether anyway, but 2) as of now, I think it should stay put, and operate just like it does now in the event of a FASS failure on the road (it would just be a backup pump).
I would like two part #’s pertaining to my fuel system –
1) Injector pump Name, Vendor and Part #,
2) Lift pump Name, vendor and part #
2) Electrical system – I’m a retired Aerospace electrical Engineer and have had to chase MANY intermittent issues like I might have here. I simply can’t see how the Chassis battery cut-off switch can be a solution to my stall problem. I agree that the stalls could be related to an electrical issue/failure, but I need to ask some more questions.
a) When I turn on the Ignition switch, I assume a number of things get activated. I hear a whole bunch of “clickety click” sound that I assume is relays or such, enabling things to happen: 1) lift pump, 2) ECM, 3) glow plugs, 4) starter solenoid, 5) etc, etc.
My first question is – Of all of those elements, Which ones , if they failed, would cause the engine to stall ? I know that the ignition switch, the ECM and perhaps the TPS could cause it to just STOP!! -- But Other relays may, or may not, so I’m interested in checking out, and perhaps changing critical elements that could cause a sudden stall. In other words for the Techs, if this was your rig and all you can do now is just “throw parts at it”, Which one or two parts would you change first?? (never got an answer to this question)
My 2nd question(s) is/are – What is the model and/or part # of my ECM? This unit has been bolted to the engine for 16 years and 67K miles in a terrible (hot) environment. Has it ever been replaced? Upgraded? Is a newer version perhaps having more features and capability available? If so what is the cost to replace? Does it even make sense? Are there other “smart electronics” functions for such as the transmission, that could likewise cause an engine stall if they malfunctioned? (don’t have an answer to this question either).
b) The reason I suspect Intermittent kind of failure is twofold:
First, The rig “heals itself” after sitting for several hours. To this old electronics engineer, that seems like a thermal-related problem. Cold solder joints will do that. So too will corroded/dirty contacts, particularly when they warm up, from resistance to the current flowing thru them. There is also an “avalanche” phenomenon that happens in diodes and transistors from operating out of design spec.(and overheating).
Second, If I try to start the engine right after the stall, It appears to go through all of the normal start-up items, including cranking the engine (and turning on the lift pump), but it won’t fire up. But let it set for a few hours, and it starts and runs smoothly. That doesn’t act like ignition switch failure to me, nor does the chassis battery cutoff switch that you replaced, fit the symptoms. The ECM is complicated enough that I could be convinced that it can cause the stall, but still be partially operational.
C) Would I change the ECM? Not necessarily, but I might want to have a spare, or at least know the part number so that I could get
one quickly if I’m travelling. Likewise, there never were any codes set (unless you found some hidden ones with your
equipment), So, if a newer better version is available that would better facilitate the forensics effort to track down the cause of
the stall, I’d like to be able to consider it. (Don’t have an answer to this question either)
a) I’d like the ECM model & Part #
Please review this with your Tech(s) and see if they have any other suggestions. I feel like some sort of sensor in the ECM OR the pump is detecting an overheated pump and somehow shutting it down. For me, that still points to the ECM (why no codes) OR air getting into the fuel supply.
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(Cummins) I forwarded your email to my lead tech and this is his response:
Morning , I’m the lead tech at Cummins and have been strictly a troubleshooter for 20 years. When it comes to cases like yours when it may take some time for a problem to appear, we usually fix what we see is broken, repair that issue and give it a try. I know that’s not very comforting but we have no idea how long it will take for the issue to show itself. That being said, the
Battery switch seemed like a good place to start, if the contacts in the switch are not making a good connection in the switch it increases the load on a circuit causing the wiring to heat up and stress the circuit. In my experience though the #1 cause of the complaint your experiencing is a restriction, we have checked the fuel system and that doesn’t mean you don’t have a restriction at certain times. There’s something we call a flapper, and what that means is a restriction ( causes fuel line to collapse?) chokes the engine til it dies and then the restriction slowly relieves itself and it acts normal again (a piece of trash in the suction line can cause this collapse). I looked at your FASS system, not a fan, when you have air in a suction line due to a restriction it starts to draw air in where ever it can. You already a have a lift pump. If it were my coach I would install a gauge directly to the main fuel pump (has to be compound gauge), maybe a clear line to be used as a tool for checking for air if and when it happens again. Then maybe we could see what’s happening. Coaches have a ton of algae problems that cause restrictions and if I had a coach I would put one on first thing.
We can install this gauge if it is something you would like to do. ( me - DO IT!)
So here’s my (lbw6303) summary of all of the above.
A) It’s probably not an electrical problem!!
B) It is more than likely a fuel system problem which could be blamed on contaminated fuel. I doubt that as well, but I will be more diligent with fuel additives and more particular about where I buy fuel.
C) It could be blamed on ULSD and the deterioration it can cause on older fuel lines causing them to become soft and to collapse from the suction (ie become a “flapper”) (I also knew my fuel tank vent line was not plugged) --- I intend to replace my primary fuel supply line from tank to primary filter and just abandon the original one in place.
D) The new supply line will come from the FASS pump installed close to the tank and connect directly to the existing Primary filter 25 ft away. I don’t intend to replace any of the other “plumbing’. The lift pump will still operate for about 20 secs on startup and then just continue to serve as the conduit to the Injector pump and steer the recirculation fuel back to the tank. The ECM won’t know and won’t care that the lift pump is still there as a backup to the old suction approach if needed, due to a FASS pump failure.
E) I will have a fuel pressure gage in the cockpit that I can monitor as we drive.
F) So for the most part, I agree with the Cummins Tech with only one exception ---- I’m currently a “Fan” of the FASS approach of “pushing” fuel rather than “sucking” it. Why Cummins and Roadmaster are so doggedly against this solution is a topic for another post. Essentially what I got was -- - Yep it’s probably fuel line restriction, but we can’t find it, nor offer a solution!!?? Color me puzzled.
Sorry this is so long. Thanks to all of you who have offered advice throughout this. I probably won’t update this thread again. Although if I discover something worth sharing, I may start a new thread. The Mn Loons are calling & I’ve gotta go North.
Lbw6303
I ain't got all the answers, but the "Clickty clicking" you hear when key is switched on is the Antilock Brake system performing self diagnostics.
The ABS controller sends a reference voltage to each abs valve, when the valve opens/closes it makes a click sound.
Unfortunately nothing to do with your main problem.
I personally had the same issue you described on a semi truck engine for a large leasing company I worked for.
Turns out there was a shop rag in the tank that was causing a sometimes fuel pick up restriction at the pick up.
That truck was towed several times, to a few different shops and a lot of parts/time and money tossed at it before I removed the tank.
Good luck!
__________________
1999 American Eagle
ASE med/heavy certified technician
ASE advanced diesel certified
I’m kinda confused here, and maybe someone can answer this. You say your injection pump is NOT a CAPS, but a HPFR. You say your getting a reading of 110 psi at the secondary filter. Can that lift pump produce this much fuel pressure? Seams high to me since minimum pressure for this pump is 20 psi.
Have you looked into the ECM cooling plate? They have a check valve that could be sticking. Could a malfunction cause fuel to be pulled through the the lift pump instead of the cooling plate after start up, causing the ECM to get hot?
Just thinking out loud.
Also, I have a CAPS pump and when I did my Fass conversion many years ago, I bypassed my lift pump. If you do your conversion I would make sure you route your fuel through the cooling plate. Hope you get this figured out.
Bill
__________________
2003 Country Coach Intrigue 36'
Cummins ISL 400
Thanks for that input. i watched the video and will keep that in mind. doesn't sound like it can actually CAUSE a stall, but can keep it from starting. Never-the-less, it's one more sensor to keep in mind. Since Cummins can't find anything, I'm still focused on the fuel system and the FASS.
I admit i'm confused about CAPS vs HPCR. I think the Pump design changed from CAPS to a new deign when they introduced the Common Rail design in 2003. My pressure gage is NOT on the Primary/Water Sep filter -- The low pressure side that goes to the lift pump. My gage is on the SECONDARY filter where it reads about 110 PSI. Cummins apparently expects to see that because that is, I guess, somewhere on the output of the injector pump (the pressure side)? I don't know the exact routing of the fuel lines to/from the secondary filter. frankly, I'm so frustrated with Cummins that I'm gonna find some other shop for repairs in the future. They keep their techs completely isolated and the service mgr types don't seem that knowledgeable. I'm gonna be relying on my FASS installer to clarify all of that for me.
Right now, i'm wanting to keep all of the plumbing, including the routing thru the existing lift pump, just the way it is. In other words -- one new supply line from the tank to the primary filter. everything else stays the same. The FASS pump would be mounted near the tank and pushing fuel to the existing primary filter. will let you all know if I somehow change that plan.
Irbw8303: RV ownership feels like this sometimes, but I assure you there is a simple solution to your problems and when you look back you will feel both relieved and secure driving your RV in the future.
The Cummins ISC engine is very robust, but when you don't have any engine codes to point you in the right direction, it can be very daunting.
Rest assured you will be able to resolve your concerns:
* Electrical
* Fuel Delivery
* Sensor related
* Ignition or ECM related
...But without a engine code, most diagnosis is based on the process of elimination. So let's start with what you are working with... CAPS or HPFR?
Up until now we have been assuming you have a CAPS pump, in the later half of 2004 some coaches (Winnebago anyway) came with HPFR injection systems.
To know what type of injection system is important for everyone to help you. Fortunately, you can easily tell the difference between a CAPS and HPFR by just looking at you injection pump.
* Does your pump have a large "block" on top? ...If it looks like picture #3 below you have a CAPS injection system like we have been discussing. The big block is known as an Accumulator and in an HPFR system you do not have one of these or 6 fuel lines coming out of a round-distributor.
* Does your injection pump look like picture #1? If so, then take look at this video to see how your fuel delivery system is designed and notice there is an ECM fuel plate and a different lift pump vs. the CAPS system.
This will help you... help us... know how to respond to your email updates in the furture. ...And FYI, I'm not surprised Cummins cannot help you, because all their repair facilities went through a major corporate "shake down" 2 years ago. IMO, you need a capable old school mechanic who can overhaul an injection pump. Maybe you can find a "Diesel Injection Shop" in your area who can held you?
Either that or you take a chance and install an airdog or fass pump and see if this helps you?
Personally, I would not rule out the crank position sensor, but I admit I'm just fishing.
Wow -- This video is VERY helpful. I just rescued my rig after two months in "Cummins purgatory". It was a white knuckle drive to my installer just wondering if/when it would stall again (kinda like a similar drive 2 months ago when i took it there. they Literally found nothing wrong and offered NO suggestions. From talking with their parts guy as I bought some spare/backup belts, I sensed an attitude of -- We fix our engines, and we carry parts for them, but whatever the "Coach guys' do is up to them and You users. Example, he couldn't, or wouldn't try to, determine what other belts (water pump, alternator, AC compressor) were on my engine besides the serpentine that they carry.
in any event, my rig is at the FASS installer's shop and He's pretty much agreeing that my plan to replace the supply line from the tank (abandon the old one) and route directly to the primary filter. The FASS pump will actually be in my filter bay, pulling fuel about 20' thru the new line from the tank and then pushing it through all of the existing plumbing, and filters, thru the lift pump up to the injector pump. It will be instrumented with a low pressure/vacuum gage on the primary filter side that will talk to a counterpart gage in the cockpit. likewise the pressure side where I already have a gage (reading 110 PSI), will be likewise instrumented to a counterpart in the cockpit. So two gages there and also a switch that will allow me to turn off the FASS and fall back to what I currently have, using only the existing lift pump. the only other thing planned right now is to put a camera down into the tank to try to get a visual of the inlet screen at the bottom of the tank. If this all works the way I think it should, the possibility of air getting into the system should be near Zero. Comments? pitfalls? suggestions?
I'll let you know as we go, but should be ready to go w/in 1-2 weeks.
I'm still unsure if you have a HPFR or CAPS pump? ...I'm guessing HPFR if you continually say you are measuring more than +15PSI at your fuel filter, but even then I'm surprised it 110 PSI! ...Not that I would know, but I thought 70PSI was nominal?
Can someone explain how fuel in a HPFR system is delivered from the tank to the Injection pump?
...And I'm unsure how adding a FASS-TS pump will fix your fuel delivery problems in this type of system, if for example you have a bad stock lift pump or the pressure relief valve issue? Maybe it will. IDK.
We hope you can find a solution to your problem soon.
Note: The pictures blow are views Back and Front of the HPRF lift pump that exists behind the ECM cooling plate. So this is different than the CAPS fuel system we all thought you were working with in the beginning.
Please verify these diagrams are representative of your fuel delivery system?
Linear Mode
