I will try to give you the abbreviated story - sorry its so long. I finally got my truck fixed last week. The problem that I had, was when the truck was up to operating temperature the engine sometimes would start to buck, it would come and go. I took it into the shop about 3 weeks ago, and the CPS and Exhaust Back Pressure Sensor codes came up. The tech replaced the CPS and sent me on my way. (he did not believe the EBPS had anything to do with my problem). I called back a couple of days later because it was still doing the same thing. I took it back in he checked the codes and again the EBPS code was back in, and he still did not believe that was the problem. We went for a test drive and he could start to feel the miss or bucking. I drove back to the shop while he played with the computer and he noticed the fuel pulse was a little weird, then he found the engine oil temperature was reading 178F and then it would drop to 52F and it would move around. Went back in and put a new engine oil temperature sensor in and went for another test drive and the oil temp stayed at 196F to 194F. The tech said when the oil temp would drop the engine would inject in more fuel to try and warm up the engine. (I think that is what he said.) That was fixed last Monday and everything is still fine. I hope someone can use this info.
This is a post by Nascarjunky years ago
