Engine/Transmission (1998.5 - 2002) I can't stands it no more...!

[ToddStephens]

My 2002 has a severe miss at idle! After it warms up to operating temperature and it idles for any length of time, she misses like a blind gunfighter shootin' a Tommy Gun ! It shakes the entire truck, but when you hit the pedal it all goes away. I've replaced the cam position sensor since I've heard that might cause this. I've heard the IAT sensor could cause it, but I haven't replaced it yet. My fuel pressure at idle is 14-15psi and I can almost pull it down to 5 or 6 psi if I try real hard @WOT. The only mods I have are a large air filter and a straight pipe. Fuel filter is changed religiously ever 15,000 miles.

It's been doing this for 40,000 miles and it's driving me insane! Other than that, I got no complaints.

Anyone else ever run into this? Know what it is?...

 

[JWelch]

Have you checked for codes. Turn key on/off 3 timesw and leave on for third time. If there are any they will appear in the odometer window. This might be the lift pump.

 

[coreyallan]

How many miles on the truck, engine, injectors? Is it the original VP?

 

[KevinSmith]

Fuel line sucking Air? Codes would really help narrow the search.

 

[ToddStephens]

No codes are being thrown. I've tried turning the key over 3 times and it brings nothing to the dash. The truck is just under 70,000 miles on the original VP. It's all original and nothing is showing up as being wrong. I haven't noticed any performance problems. From time to time I pull a 1 ton Ford on a 20' trailer and it pulls it just fine. I'm confused to say the least! Thanks for your help!!

 

[JKinney]

I would guess dirty injectors

 

[coreyallan]

I was also under that impression, mabey a bad injector or injectors. Kinda far feched but? I had a 97 chew cab Ford w a 7. 3 in it and my buddie had diagnostic eqpt that could test the injectors individually when the truck was running dunno if the same applies for a Dodge. .

 

[ToddStephens]

I run Red Line diesel injector cleaner thru it from time to time. Maybe I should pull them out and give them a bath.

 

[JKinney]

Mine was doing that, I picked up a set of rv 275s dropped them in, no more stumble.

 

[DCreed]

with only 70k on the clock isnt it still under warr. ?

 

[draymorris]

I posted a similar issue on a thread that was started about my low power and my turbo (sorry I don't know how to insert links to threads).



I have a the same problem,just not as rough at idle.



Can one clean the injectors? If so, how?

 

[ThrottleJockey]

Double the amount of fuel injector cleaner next tankful and CLEAN the IAT and the MAP sensor at the same time.



Then take it out and drive it like you stole it.

 

[draymorris]

Is the IAT Intake Air Temp?

Where is it located?

Would either one throw a code if they were not reading correct?

Thanks

 

[ThrottleJockey]

Nah, it will just idle like crap.



IAT is intake temp sensor, yes.

 

[JR2]

Here is a thread that started it all... as far as the IAT goes.

https://www.turbodieselregister.com...ion-1998-5-2002/11726-iat-sensor-cleaned.html