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jprisbe · 06-02-2013, 01:10 PM

1995 F53 chassis.
Last Sunday I went to start her up and the engine would turn over fine but she would not fire up.
Checked for spark and I had good spark.
Checked the inertia switch and it was not tripped.
Attached the fuel pressure gauge and when I turned the key to on it showed 0 (zero) psi.
While doing this I noticed that I did not hear any relays click as I turned her to on.
Next I grounded pin 6 of the test connect and still nothing. All of a sudden, while pin 6 was grounded and the key was turned to on, I heard a click... fuel pressure shot up to 35 psi so I turned the key and she fired right up. While running the fuel pressure settled at 30 psi. As I pressed the accelerator the fuel pressure rose and then settled back to 30 psi with the accelerator still depressed.

Monday morning she fired right up so we took a chance and went on vacation. Drove two hours on the freeway, up and down hills and she ran just fine. No hesitation, fuel mileage seems unchanged, no back firing or anything. Three days into vacation I tried starting her again and again she would not start until I grounded pin 6.

This morning when we left for home I again had to ground pin 6 but it seems like the ground did not do anything at first until I turned the key off and on a few times then I heard the click and she fired right up. Drove the two hours home on the freeway and she ran just fine.

One other note... last July I had this on a trip up north. After two hours of driving we stopped at a rest area and when we went to leave she would not start. Waited about a hour and then she started right up. Did not have a fuel pressure gauge then. I did replace the fuel pump relay at that time and we never had another problem till this week.

Does this sound like a bad fuel pump or something else?

subford · 06-02-2013, 01:18 PM

I would replace the PCM Power relay and the Fuel Pump relay.
You could just for a test just swap them with the blower relay and the horn relay.
As for the fuel pump it sounds like it is OK.

TeJay · 06-02-2013, 02:09 PM

With a coach that age it could still be the fuel pump. Just yesterday I was out working in the garage and noticed a Dodge truck in my driveway. It was a couple of workers that had stopped because their truck would not start. They new a little about what to check but not to much. I found the schrader valve on the fuel rail. I showed them how to check for fuel. It did have some fuel coming out but not under much pressure. They were about to call a tow truck so I went into the garage and got a dead blow hammer. I told the helper to reach under and smack the fuel tank a few times. He did and it started right up. Those fuel pumps can become corroded and not work all the time. Maybe grounding pin #6 allows a few more volt to the pump and it starts. Who's to say what voltage drops might be present on the usual route to the fuel pump. As mentioned the relay contacts may be slightly corroded and losing some voltage through those contacts. I think you are on the right track.

TeJay

subford · 06-02-2013, 02:32 PM

A bad fuel pump will not stop the relays from clicking.
He has either bad relays or a bad ground as he said it would crank and did have spark when it did not start.
But he did not hear the PCM Power Relay or the Fuel Pump Relay click when he turned on the key.
So that tells us he has power going to the coil of the PCM Power Relay because he had spark. So the only thing left is a bad relay or a bad ground for the relay coil.

I would bet on a bad ground or relay.

jprisbe · 06-02-2013, 04:34 PM

Thanks guys.

I'm going to try swapping relays after work tomorrow and see what happens.

flbicyclist · 06-02-2013, 04:39 PM

jprisbe- fellow Firan owner.
I can't help with your starting problem but subford;s diagnosis sounds spot on & during the 5 months that I've mostly lurked on iRV2 his posts have been very helpful in enhancing my overall RV knowledge. I also own a 96 FIRAN Raven XL with 2 minor differences. Mine is a 34 footer & my F53 was manufactured 4/96. http://www.irv2.com/forums/f84/1996-...wb-161308.html Ive sent you a link to my previous thread in order to give you some context . Perhaps you have the original owners manual?, do you know what the ," Arctic Package", button actually does. In my rig it is located next to the water heater button in the kitchen. Thanks for any help you can provide & as I continue to upgrade and adapt the MH to my wife's changing medical state, I will post photos and share info if you need.

jprisbe · 06-02-2013, 05:04 PM

Hi, FLBICYCLIST.

Glad to meet a fellow Firan owner. The arctic package is the holding tank heaters. If you look on top of the tanks you will see the heating pads.

I do have the owners manual. We bought our Firan 3 years ago and up till now have had no issues with it.

flbicyclist · 06-02-2013, 08:10 PM

thanks for the quick reply jprisbe. I suspected the tank heaters but in the times that I've been under the coach while working on wiring projects the large volume of foam insulation prevented me from spotting the heating grids. My rig has been in Florida for the last 12 years as the owner was a neighbor so that the arctic package was not important. In the next couple of months I should be able to complete all the upgrades and will take the MH to NY several times a year so it will be nice to have the tank heaters though I'll still use antifreeze out of an abundance of caution & past mistakes on my part. For the past 25 years I've owned several RV's ,(A,B & C class) so that systems & appliances are familiar but it would still be nice to have the manual. Please send me a private message so that I can give you contact information & of course I'll compensate for your time as well as all expenses.
I am generally impressed with the overall construction quality of the Firan . Well above average for a MH of this vintage. As best as I've been able to research 96 was the last year of production as Firan was bought by another manufacturer for their production facilities & the brand was discontinued. Maybe you or others have better info as it would be nice to know.
My rig has a BIG FOOT leveling system made by QUADDRO Mfg. which is located in your neck of the woods, (Michigan). I've had some issues with the left front retraction. will check fluid level tomorrow & contact them if that isn't the issue.
I hope you can solve your starting problem.

Mekanic · 06-02-2013, 08:29 PM

Quote:

Originally Posted by jprisbe

1995 F53 chassis.
Last Sunday I went to start her up and the engine would turn over fine but she would not fire up.
Checked for spark and I had good spark.
Checked the inertia switch and it was not tripped.
Attached the fuel pressure gauge and when I turned the key to on it showed 0 (zero) psi.
While doing this I noticed that I did not hear any relays click as I turned her to on.
Next I grounded pin 6 of the test connect and still nothing. All of a sudden, while pin 6 was grounded and the key was turned to on, I heard a click... fuel pressure shot up to 35 psi so I turned the key and she fired right up. While running the fuel pressure settled at 30 psi. As I pressed the accelerator the fuel pressure rose and then settled back to 30 psi with the accelerator still depressed.

Monday morning she fired right up so we took a chance and went on vacation. Drove two hours on the freeway, up and down hills and she ran just fine. No hesitation, fuel mileage seems unchanged, no back firing or anything. Three days into vacation I tried starting her again and again she would not start until I grounded pin 6.

This morning when we left for home I again had to ground pin 6 but it seems like the ground did not do anything at first until I turned the key off and on a few times then I heard the click and she fired right up. Drove the two hours home on the freeway and she ran just fine.

One other note... last July I had this on a trip up north. After two hours of driving we stopped at a rest area and when we went to leave she would not start. Waited about a hour and then she started right up. Did not have a fuel pressure gauge then. I did replace the fuel pump relay at that time and we never had another problem till this week.

Does this sound like a bad fuel pump or something else?

What I underlined is Normal pressure. There is a pressure regulator on the fuel rail that uses manifold vacuum to regulate fuel pressure.
Sounds like you have intermittent grounds issues .

DFWtechie · 06-03-2013, 04:59 PM

Also you may want to check the Relay in the fuse box, I had an issue with the AC in my work truck and the compressor intermittently turning the compressor on. Turned out the prongs on the relay were not getting a good connection in the fuse panel and they bent the prongs slightly so the relay fit in the plug tighter. Long story short the fuse panel needs replaced but my The Multi billion dollar company I work for is to cheap.