HELP Please! Bucking//Shuddering in Overdrive
I need advice on a major studder in OD and a slight up and down idle. Just got done installing injectors that were rebuilt to 155cc by Warren Diesel after hearing nothing but good things. They claim that my issue is more than likely an injector not sealing properly. I am somewhat skeptical about their diagnosis. Also, I know a lot of you will tell me that I should have only gone with OEM replacements or Alliant injectors, but since mine were doing so well prior to the solenoids/coils getting fried I thought having them rebuilt was worth a shot.
I torqued them down to 30 ft/lbs. They recommend 32 ft/lbs. I did not clean out the injector cups with a brush or anything like that, but I did blow out the injector hold down bolt holes. They said if my injectors were sticking that it would show up during cold starts and not just in OD.
Like I said my injectors were all doing great prior to my FICM frying and taking several out on the electrical side with it. Now after having them repaired and reinstalling them this issue has showed up. The truck doesn't feel like it has quite as much power as it did before the problem. Plus while I was getting my FICM rebuilt I got the ATLAS 40 tune on it and also had my ECM strategy rolled back to a VXCF4 stategy so that along with 155cc injectors with stock nozzles you would think I'd have more power. Also, why would my injectors suddenly be sticking?
What should I do to properly diagnose my problem? Warren Diesel said I will have to pull injectors until I find the one that is leaking past the copper gasket. A mechanic I trust said that the symptoms would be diffrent if that was the case. I am at a loss. I have an AE scan tool. Should I do a Power Balance test? I will probably do a buzz test while I am at it, but don't forsee that showing any issues since Warren Diesel just tested them. Because of the sudden onset I am convinced it is injector related but don't know how to best diagnose which injector is giving me fits. Is it a sealing issue or a sticking issue? If so what is sticking? The spool valve? Wouldn't that show up on cold starts as well? It starts fine with no bucking/rough running. Any advice is greatly appreciated.
Last edited by 03RaptorCV; 05-05-2013 at 09:37 AM.