8.1L Vortec Issue

[TurboToys]

Good evening everyone,

I have a 2001 Condor by R-Vision class a with the 8.1L Vortec V8. It only has 11k miles but has been sitting for around 10 years. Having trouble getting it running correctly. We have replaced the plugs, plug wires, TPS, cleaned the EGR. It’ll start but idles at 250ish RPMs. RPMs won’t go over 700ish even on the gas pedal. Batteries are super dead obviously not sure if that could be why (been jump starting it with my truck). The check engine light and reduced engine power light are on. I tried to plug in my code reader but it wouldnt read the codes for some reason. Also, it had less than a 1/4 tank of gas in it, we added 15 gallons of fresh gas with Lucas treatment. Any help would be greatly appreciated, thank you.

[Full-Timers]

A dead battery would sure do it. The computers won't operate under 9 volts.

[Massparanoia]

Originally Posted by TurboToys

Good evening everyone,

I have a 2001 Condor by R-Vision class a with the 8.1L Vortec V8. It only has 11k miles but has been sitting for around 10 years. Having trouble getting it running correctly. We have replaced the plugs, plug wires, TPS, cleaned the EGR. It’ll start but idles at 250ish RPMs. RPMs won’t go over 700ish even on the gas pedal. Batteries are super dead obviously not sure if that could be why (been jump starting it with my truck). The check engine light and reduced engine power light are on. I tried to plug in my code reader but it wouldnt read the codes for some reason. Also, it had less than a 1/4 tank of gas in it, we added 15 gallons of fresh gas with Lucas treatment. Any help would be greatly appreciated, thank you.

Replace the battery. Drain all the fuel out of it, flush the tank and replace fuel filter

[SmilingSam]

the car guys would have drained all the gas not just add, old stale 10yr old gas is a no-no, and car guys go by smell, and if not gas smell should have dumped it all !!


also, ALL fluids should be changed rad, engine and brakes, but smell & appearance again is key to brake fluids but why not change it ?


also the throttle position sensor may be bad - but get those code read - it will help you figure this out !!!



borrow or buy a good obdII reader with LIVE data capability, will be useful for all vehicles, spend the ~$130 or so for a good reader !!


google - how to get old barn find up and running - should tell you the MUST DOs !!



GL


ps: was recently looking at used mh and many had only 10k mi but were 20yrs old, so new buyer OR dealer would have to do all that you need to do.

[LETMGROW]

You need a good battery before going any farther. You should also remove the air filter and the Mass Air Flow sensor (MAF) and give the sensor a good cleaning with cleaner made for this purpose available at most auto supply stores. Replace the air filter, and if you haven't already, replace the fuel filter.
You may need to have someone check your systems with a true diagnostic scan and data tool rather than just a code reader

[MrMark52]

I’m using a Foxwell N301 scanner to diagnose our ‘02 8.1 (If I were to buy again today, I would get the N600 version).

I agree with everyone who say it would have been better to drain the old fuel. It’s not too late to do so.

I would drop the tank to get rid of all the old gas. Running it dry with the fuel pump is not good for the fuel pump as any solids will clog the filter on the pump. Plus you can flush the tank with a cleaner, and then you might as well replace the fuel pump with a quality replacement.
Then, replace the line filter on the chassis rail just above the rear axle.

Check for a failed fuel dampener/regulator on the fuel rail - top side, driver side left. I found mine was bad by simply pulling the vacuum hose off of it after the engine had not run for several days. Fuel spewed out. That shouldn’t happen, at all!
Failure of the dampener dumps raw unmetered fuel into the intake manifold between #7 and #8.

Once you’ve confirmed it’s condition, go to O’Reilly’s or AutoZone and borrow a fuel pressure test kit. There is a test port on the fuel rail above #4. Pressure should be something like 50 to 65 pounds (see service manual for the Workhorse).

And then once you get the engine running, do a hard look at all coolant lines and radiator hoses, belts, and tires.
You may not need new plugs, but you might as well change them while your replacing and upgrading your plug wires to Magnum’s from Brazels.
Do a complete flush of the brake hydraulic fluid (I would do this one 2-3 times over the next 3-6 months). I would recommend replacing the two front and 1 rear hose to be on the safe side.
Oil and tranny fluid change with filter replacements. If your tranny is an Allison 1000, do the TranSynd flush and upgrade (your tranny I’ll love you for it - mine had champagne, chocolates, and flowers waiting for me the next morning after I did the change). 😀
Radiator touch and refill.
Full chassis lube.
New shocks (yes, shocks can age out).

After all that, hopefully you’ll have enough $ left over to go on your first trip. 😀

[Arch Hoagland]

Replace the battery and then see what happens.

[ktoutoor]

Make sure batter cables are tight especially the ground cable from the battery down to the frame. A bad ground at the frame can cause all kinds of trouble.

[TurboToys]

Fuel was drained, including most of the system, filled with 15 gallons of fresh gas. Replaced all 3 batteries with brand new ones. Still the same issues, idling at 250 rpms, won’t even get up to 1000rpms using the throttle. Cleaned the MAF sensor too. Maybe crankshaft position sensor? Or MAP sensor? OBD2 port is not functioning properly. Unable to read the codes

[MrMark52]

Originally Posted by TurboToys

Fuel was drained, including most of the system, filled with 15 gallons of fresh gas. Replaced all 3 batteries with brand new ones. Still the same issues, idling at 250 rpms, won’t even get up to 1000rpms using the throttle. Cleaned the MAF sensor too. Maybe crankshaft position sensor? Or MAP sensor? OBD2 port is not functioning properly. Unable to read the codes

Measure fuel rail pressure?

Did you check the fuel dampner/regulator on the fuel rail? Remove the vacuum line from the dampner - do you see any fuel what-so-ever in the vacuum line?

While I doubt an issue, but have you checked all vacuum lines - there is one going to a vacuum reservoir up near the radiator, the one at the fuel dampner/regulator, and one headed to the EVAP canister (left side of engine going back to under the floorboard)?

What do you see and smell coming out of the exhaust?

Have you pulled any plugs since replacing to see if they were wet, and if so, what? Coolant? Oil? Gas?

Is the radiator burping (pressurizing) as a result of blown head gasket(s)?

Have you tried a different OBDII scanner to make sure the issue isn’t your scanner?
Like I think I mentioned before - I’m using a Foxwell N301 and getting everything I need but the tranny fluid temp.

Really need codes! Your shooting in the dark, guessing, without. Even KOEO codes are probably better info than running engine codes would be at this point.

Not to mention I didn’t think any gasoline engine would run 250 RPM without assistance from the starter.

[jeff0210]

Not sure if they brake down over time. My truck had same issues after numerous miles. Cat's were clogged. Pull the O2 censors ahead of the cats and see if the air flow improves. If it does that could be your problem. A plugged exhaust of some sort. Heck...could have dead critters up in there somewhere. Good luck.

[F4Gary]

I love how some folks suggest drain or drop the tank like it's no more difficult than draining the oil.
Out tanks don't have drain plugs, unfortunately, and dropping a tank is a major undertaking. Not many of us can do that.

[crawford111]

This sounds like the exhaust system is close up or chocked off. maybe disconnect cat see if the power comes back.?

[Kluffinator]

Have you checked the throttle body for a sticky butterfly?