My 04 has recently started idling real rough. I did some searching on this site and found some that said to run an injector cleaner in the tank and in fuel filter canister. i did this and also ran the truck pretty hard for about a week but the shake seems to only get worse. Any ideas or advice?

Thanks

Eli

 

Does it idle rough all the time or just at start up? Make sure you are not idling the truck for long periods of time. This can cause the injectors to clog up.

 

How many miles on the truck? Maybe you need to change the fule filter, don't wait until the recommended time to chnge the filter. I have to change mine evey season adn or every 10-12k miles. You propably got some bad fuel and need to change it anyway.

 

I don't Idle the truck at all and i change my fuel filter every 5-10k. The truck has 79k on the odometer. I am wondering if this is a sign of an injector or lift pump or some kind of valve or sensor in the injector pump. what do you think?

Eli

 

does it only idle rough at start up?

 

No it idles rough all the time. It seems to get worse once it is warmed up.

 

I have had this happen a couple of times.
All I did was shut the truck off and open the water drain on the filter housing and drained a bit of fuel and the truck ran perfect afterwards.
NOTE: I did not get a dash light warning of water in the system...I just did the drain thing as it was easy and free...and it has worked for me a couple of times.....now whether or not I actually had water in the system...or turning off the engine did a reset, I don't know....but it worked.

 

Mine had a slight shake @ idle with a/c on not real bad but you could notice it . I also had excess black smoke under load or excelleration. pulling a trailer it would smoke all the time. It was 3 leaking injectors, a new set (with high flow nozzles) and all is fine. You might want to try some power service for a couple of tanks.

 

Taking it to the dealer today to have them check it out. thanks for your input. My guess is that it is an injector. we will see I guess. Anybody know if the dealers keep injectors in stock or is this going to be a long drawn out deal if it is an injector. thanks

Eli

 

Did you try pulling your Dr Perf box off first? That's the first thing I would have looked at...

 

yes the box is off and it is still acting up. I took it to the dealer tech who is a friend of mine and a diesel genius and he hooked up the computer to it and no codes were thrown. He said that north texas has been getting some bad fuel lately and to run some CRC diesel injector cleaner for a few tanks to see if that helps. He did the injector kill test on each injector and there was no change when he killed them. He said if the CRC doesn't work then they will probably have to replace all of the injectors. Either way is fine since it is under warranty.

Eli

 

Under warranty?? Injector or a dropped valve seat due to a fueling box.

 

It is my understanding that the dr performance box is not a fueling box which means that it doesn't boost fuel pressure in the rail. I am starting to believe that it may not be an injector. I have been running the cleaner through the tank and it seems to only get worse. What would be the symptoms of a damaged valve seat?

Eli

 

Rough idle.maybe a noise,low compression etc. some have also reported dropped valve seats and usually if not all were running a box.High EGT spikes.

 

Eli - were you running an EGT (pyro) gauge along with your Dr. Perf box?

Otherwise,