Running problems. Need help

[LWDUPPONG]

I posted a while back about my truck stumbling after startup. It was recommended I try some 2 cycle oil to see if it helps. It seemed to help but it was hard to be sure since I basically run a full tank through every time I fill.

It will stumble after I start it but not to the point of dying out. It also started several other "symptoms". It is worse after it's hot. #1. It will idle smooth and stumble the same as it does after start up. #2. while it is idling it seems to advance the timing for a split second and have more clatter from the engine. It used to do it occasionally but now it is about every 15 to 30 seconds. again it is worse when it is hot. #3. When I go to take of from a dead stop and start to let the clutch out it will drop rpm's and then rev up almost like it is starving for fuel for a second or 2. Again worse when it is hot. #4. It has been surging, not bad but noticable. I mainly drive interstate with a load but I have noticed it when running empty also. No codes have shown up.



I recently installed a FASS 95 pump to get rid of the stock lift pump problems but it didn't seem to help this problem.



I am open to any input you can give me.

 

[blacksheepdiesel]

What is your fuel pressure at the injection pump?



Godspeed,

Trent

 

[p-Bar]

Your system is a HPCR I assume . I would try replacing the FCA on the back of the CP3 injection pump.

 

[LWDUPPONG]

I'm not sure what the pressure is at the rail and it is the common rail system. I had read numerous threads about the FCA and even mentoned to the local Cummins service manager. He didn't know what the FCA was.

 

[TCDiesel]

Factory Pumps DO NOT Like the Pressure Most of the aftermarket Pumps Produce. The NEW Pumps Will leak if pressure exceeds 12PSI when we Mod New Pumps we machine a New snap-ring like former pumps had. You are welcome to try our test sensors (Pressure,LV,FCA,MAP,COV) You must promised to return these, I use to just let them be used But do to the fact People abused this I now require a $300. 00 deposit which will be refunded when returned, 15 days is the Max allowed Time unless we are contacted.

 

[JJPage]

FCA / fuel control actuator. You mentioned that you believe it periodically seems to advance timing, because of increased rattle. You could have a crank or cam shaft position sensor going bad, first I would check their connections, look for worn or chaffed wiring, maybe you can duplicate the symptom by wiggling the connection while the truck is idling. You may try the same with the FCA connection, without any codes showing it is very hard to isolate, and it gets expensive replacing parts for no good reason.



The FCA is just over $100. 00 at Cummins, I believe the sensors (crank/cam) are less, but not sure. There was a post a couple years back about a wire from the alternator rubbing on the AC refrigerant line on the passenger side of the motor, causing wierd intermittent problems, may want to check that also.

 

[p-Bar]

I'm not sure what the pressure is at the rail and it is the common rail system. I had read numerous threads about the FCA and even mentoned to the local Cummins service manager. He didn't know what the FCA was.

Not sure if I would be taking my truck there. Or maybe it's the PETER principle promoted to the level of their incompetency. Any how did you try the 2 stroke oil in the fuel tank ??

 

[LWDUPPONG]

I finally found the problem. FCA was going bad. I found some info that was the identical symptoms I had. Put The new FCA in and it fixed all of the symptoms. Thanks to all the input.