No first swap coil to another cylender & change plugs (inspect all plugs but especially cyl 4....if still skipping compression test followed by leak down test...most of the ones I see with the heads off are not customer work...just H3's that are for sale that didn't have monitors set..(we set monitors before selling) if it was a customer off the street we don't try to sell them BS services that don't work most of the time like fuel injector services,etc...we do above steps. You obviously did not read what Tainter & original poster posted...

 

I just replaced all my Sparkplugs, cleaned trottle body swap cyl. 4 coil, and this morning P0304 again so now I know it's not the spark plug or the coil. My warranty expired in November 2013 but in October 2013 they checked it at the dealership for a P0304 and swapped the coil and swapped the spark plugs. Anyone knows if they should still repair it under warranty?

 

. That depends on the dealership...I would definetly call and see what they are willing to do...

 

I want to say thank you to all and the forum for the help. After spendind alot of time and money trying to track down my rough idle I looked up my issue here. I found this post and decided to try and clean the TB and what do you know my H3 runs like a baby again. Almost 100k on it and she still runs great. $15 and about 30 minuets of my time and my issue is fixed... I cant believe the dealer couldnt even fix this. I think I will check here first next time.

Thanks again to all.

 

Excellent work! Nice to see you read between the lines, there are many that want to start by taking your head off.

 

First off to the guy who first posted this when you tighten down your bolts to your intake manifold and and a few days later the code came back well when your valve cover blows out oil you dont tighten the bolts more thinking the gasket will hold up you "replace" the "GASKET" to "Fix" the problem because once a gasket starts to leak or has been exsposed its been compromised meaning its junk and time for a new one .If your engine light is on solid its not to bad but if its blinking then you have bigger problems and what I mean is if its solid theres a 2 second difference in the timing and if its flashing theres a 10 second difference in the timing. And dont listen to "TAINTER" when he said " YOU HAVE TO USE ACDELCO OR IT WONT WORK" because I dont use nothing but "BOSCH" in my hummer h3 and ACDELCO is JUNK to me and ive been a mechanic for over 13 years and now my story I had this code come up and looked into it and the first step I did was flip flopped all the coils and still the engine light was on replacd spark plugs still the light was on then I replaced the throttle body still the light was on then the mass air flow sensor still the light was on and then I checked the INTAKE MANIFOLD bolts to see if any where loose and sure as hell there was one loose and I took off the manifold and put a new FELPRO GASKET in and my engine light went bye bye

 

Welcome to HF and the electrifying post in a TWO YEAR OLD thread!

https://www.hummerforums.com/forum/n...bumping-23220/

 

Thanks too for the headache I got trying to follow that long run on sentence.

 

[QUOTE=Doc Olds;343863]Welcome to HF and the electrifying post in a TWO YEAR OLD thread!

Time for a new calendar Doc. 3 Year old thread!

 

[QUOTE=Broken Halo;343868]OK, OK.............. you got me. THREE YEAR OLD Thread!!!!!