cletuz

Hi guys, I have a 2003 1500HD LQ4 with 295000KM. It runs really well most of the time, save for a couple little intermittent issues. Occasionally at idle, out of the blue it will go into an extremely rough idle - as if it's dead missing on several cylinders and then clear right up. It's so intermittent that I haven't been able to catch it on my scan tool. The truck also sometimes slightly misses under light acceleration - it's got a performance muffler and I can hear it sputter when gently accelerating at low speeds. The truck has lots of new parts that I have installed in the past to get my LTFT's down: New upstream O2 sensors (both cycling well now), new exhaust manifold gaskets with stainless bolts, new intake manifold gaskets (injectors were checked for debris and cleaned), new injector o-rings. LTFT's are around 3 at idle and 7 ish while cruising which satisfies me, I don't have any reason to believe I have any vacuum leaks. My next step was going to purchase a fuel pressure gauge and see if the rough idle correlates with a drop in fuel pressure. Any other advice I'm happy to hear, thanks for reading.

Hi guys, I am about to purchase a 2004 1500HD tomorrow, I have to drive 800 km each way to purchase it. I'm friends with the previous owner who's selling it to me for a very good price. It has some drivability concerns - low on power and misfiring (sometimes through the exhaust). It has a slew of trouble codes that keep returning even after he threw tons of parts at it. Some parts being all new coils/plugs, fuel injectors, crank sensor (he hasn't done a CKP relearn since) and a couple of the O2 sensors. Being that I have a long drive ahead of me with the truck, I was wondering if anyone here might be able to lend a hand in some parking lot diagnosis of the truck once I get to it tomorrow. This will be my first time dealing with a gas chevy V-8. I am hoping that there is possibly simply a ground issue that might clear things up as this list of codes seems too long and unrelated to all be occurring at the same time. Any advice on things to check would be greatly appreciated. I'll have my scanner and multimeter with me as well. Cheers.