Hello Everyone, I have an issue with my H2 for the past 3 years.
On a cold start its smooth and perfect but when the engine temp. goes above 95c a random misfire starts on idle, no other issues at all.
Previously i had a short in the engine harness causing the engine to stall under random conditions. i got this sorted out and the vehicle doesn't stall anymore and works normally except for the misfire which can be felt when engine shakes.
Before knowing that there is a short in the harness i have replcaed the following parts with new ones:
1- MAF
2- Alternator
3- Fuel Pump (3 Times)
4- Fuel Pedal assembly
5- Throttle Body and gasket
6- ECU
7- Crankshaft sensor
8- Spark Plugs and Wires
9- Two coils
10- A\C clutch
11- MAP
12- Manifold gasket
13- Fixed Hydrolic steering oil leakage
14- Intake filter with heat resistant straight tube
After fixing the short i replaced the following:
1- MAF
2- Battery
3- Cleaned Grounds
4- ECU with stock tune
5- A\C internal fan
6- A\C fan controller
7- Tranny filter and gasket
8- Tranny cooler
and nothing has changed, it still misfires and shakes on idle.
Note: I live in the middle east in one of the highest temp countries in the world(Kuwait).
I have ran some scans but due to my limited knoweledge i have no idea what is wrong.
Your help is highly appreciated.
Thanks.8Aug2020 5PM Hummer H2 Log.hpl9Aug2020 Humer H2 730PM.hpl9Aug2020 Humer H2 815PM.hpl9Aug2020 Humer H2 820PM.hpl