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Hummer H3For the Hummer driver who wants the rugged look and off road capabilities of the Hummer, but in a smaller size and with a more fuel economy friendly engine.
How is it dangerous? been my go to test for many decades, also works great when I have to pull a towed in parking lot drop, fuel pump failure, into the shop, to repair. You can also try starting fluid, which may cause damage to the engine, or throttle body cleaner works too. If it starts, then you have a fuel issue, if not, you know there's another problem.
Btw, as state above you can take a prybar on the CK pulley and see if moves.
Update... Root of my problem was that the timing belt tensioner broke. The oil on top of the valve cover was a small crack (now fixed). A bag of money later and my engine has been rebuilt. Runs great...
Problem - I still have the infamous stalling when the truck is warmed up and coming to a stop. It does not happen in the first 10 mins when truck is cold. After than, RPMs bounce around and it periodically stalls unless I hold the RPMs wit hthe gas pedal while slowing down to a stop.
Any ideas? Ive read a lot here and online re this stalling issue. Ive removed and cleaned TB 2X, MAF 2X, tried changing the EGR valve. What next? Thinking O2 sensors, MAP sensor, fuel filter/pump.... Also booked an appt w dealer to update PCM (fingers crossed).
Thanks.
Last edited by gwarrend; Nov 26, 2020 at 12:13 PM.
I changed my Camshaft Position Sensor to a generic amazon one. Today I bought an AC Delco and now the truck seems to idle better but still stalls when the truck is warmed up and harder braking/stopping.
Thanks Doc. I have checked and the manifold is tight.
Yesterday, I did a number of hard stops to simulate and diagnose. One time the Word OIL flashed on the dash so I pulled over and checked .... the oil was at the bottom of dipstick. Odd since engine was rebuilt 1200 kms ago. I topped up the oil and has not stalled since. Guess H#s have an auto shutoff for where the oil gets too low. Will continue to monitor. Fingers crossed I don't have a leak somewhere.
Thanks Doc. I have checked and the manifold is tight.
Yesterday, I did a number of hard stops to simulate and diagnose. One time the Word OIL flashed on the dash so I pulled over and checked .... the oil was at the bottom of dipstick. Odd since engine was rebuilt 1200 kms ago. I topped up the oil and has not stalled since. Guess H#s have an auto shutoff for where the oil gets too low. Will continue to monitor. Fingers crossed I don't have a leak somewhere.
Was this resolved . I am having the same symptoms and I am now afraid that if I replace the timing chain and tensioners, it might be something else. The truck is throwing errors p0016, p0017, p0365 and p0366.
Was this resolved . I am having the same symptoms and I am now afraid that if I replace the timing chain and tensioners, it might be something else. The truck is throwing errors p0016, p0017, p0365 and p0366.
Help!
One more thing. When the truck is at idle , the oil light comes on and if I accelerate, the light goes out. The stalling only happens sometimes when starting the truck.
Was this resolved . I am having the same symptoms and I am now afraid that if I replace the timing chain and tensioners, it might be something else. The truck is throwing errors p0016, p0017, p0365 and p0366.
been my go to test for many decades, also works great when I have to pull a towed in parking lot drop, fuel pump failure, into the shop, to repair. 
You can also try starting fluid, which may cause damage to the engine, or throttle body cleaner works too. If it starts, then you have a fuel issue, if not, you know there's another problem.
