I have a problem with my v10. It is a 1999 dodge 3500, 4x4 dually extended cab. With 75,000 miles. The truck will start fine then in about 2 min. it will start to run rough, but is alot worse when warm, if you step on the gas it coughs and backfires. Doesn't throw on the check engine light. I did have it on the scanner when it acted up and it says Runs lean. Checked all hoses, O2 sensor tested ok, catalytic converters seem to be cracked, but when taken out, problem continues. Anyone run into the same problem or have any ideas? Thanks.

 

Is there a sensor behind the converter? If so, you need to reinstall a converter or get an oxygen sensor simulator.

Also, check your fuel pressure. A weak pump can cause issues similar to this. I know this from experience.

If it runs bad when it's warm, it could also be an issue with the Idle speed motor or the throttle position sensor. Their input is what matters after the truck is out of "warm-up" mode.

Also, make sure you've done this: http://p211.ezboard.com/fdodgeramv10...icID=292.topic

 

Thanks for responding. I read about the wire problem in a recall forum. I checked and mine are wired correctly. No sensors behind the converters. I have replaced the idle speed motor and trottle position sensor - no luck. There is a drop in the fuel pressure. But, I didn't think a bad fuel pump would act up, but be a continuous problem. Once it gets out of this warm mode, it runs fine down the road. It doesn't happen on a cold start.

 

I wish people would follow up with answers or things they have tried. My 95 Dually 4x4 v10 is doing the same thing. 2 minutes after a cold start up I hear a slight stumble and the check engine light is on for "Left bank Lean. Funny thing is when it is in closed loop for the 2 minutes it is running perfect.

The 5 and 7 wires are routed correctly, plugs and wires are a few years old.
New O2 sensors and have same problem.
I have swapped out both coolant sensors, IAT, The throttle body including TPS and IAC.

I was able to get a snap-on MT2500 scanner and look at what is going on.
When initially started the O2's look OK, but as it gets warmer the left bank definately goes lean. The Long term adaptive I believe was 27%.

I had 40 PSI on the fuel rail, but decided to put a new pump and filter/regulator.
Still have 40 PSI now.

I decided to pull the upper intake to remove the fuel rail to look for rust in the line and check the injectors.

Pulled the intake and found the EGR valve. The EGR solenoid has a plastic diaphram that was melted. As I read in the service manual the EGR should not be able to function without the diaphragm working.

I went ahead and pulled the fuel rail off and it was clean as far as i could tell by looking.
I inspected the injector inlet screens and they looked clean as well.

I pulled the injectors out of the intake, connected them to the fuel rail that is now off the truck, connected the old fuel pump/filter regulator and used a Snap-On injector testor to pulse the injectors.
All the injectors seemed to have the same flow pattern which was like a pencil. I was expecting more of a cone pattern, but I ran the same test on a set of 96 V10 injectors and they also looked like a pencil.

I am going to swap the injectors from left bank to right.
put an EGR block plate on.
Plug the EGR vac line and leave the solenoid connected so it doesnt throw a code.
RE-TEST

If this gives the same problem next I will look into the ignition, wires, coils, module, as I have access to another V10 truck that runs perfect.

My concern is that I thought somewhere in the past I had read that some higher mileage V10 heads could develop cracks in the intake port. That could definately cause a side to go lean. I have not been able to find any information to verify that. Or even if pulling the valve cover would help in looking for cracks.

So if anyone has had this problem and fixed it I would sure like to hear from them.

 

I replaced the intake manifold gasket and that seems to have fixed the problem. I did make a block off plate for the egr while I was in there.