Off Road fueling problem!
 

Hi Guys,

Would like to ask if anyone has had this problem.

Hummer H3 2007 3.7lt runs fine on all road conditions, but when off road and after having driven around at angles, a fueling problem develops, I can be driving up a long hill ascent and she suddenly starts to struggle for fuel and sometimes stalls. Once this has happened the H3 struggles to start as if fuel isn?t getting pumped through or air has got into the system. Get the H3 back to level then fuel seems to pump through but more often than not it also continues to struggle to start. After I?ve had this problem, it seems to go into limp mode where power is held back from the engine, can drive it around on a flat surface and its got no pickup and no power, if I keep switching it off and on at some point the engine management light comes on and detects there is or has been a problem, I've worked out that once the engine managment light is on, I can switch the H3 off, disconnect the battery which re-sets the engine management system and all is fine again, full power is back until the same starvation problem happens again.

I?ve done a number of mods and wondering if it?s a mod I?ve done, or has anyone experienced the same problem with a stock standard H3.

Mods done.

Throttle body spacer
Air filter
Branch
Free flow exhaust
Extended fuel tank, but I isolated that for testing this weekend and still same problem


Advice welcome.

Cheers

Adrian

Re: Off Road fueling problem!
 

Try removing the TB spacer.

Re: Off Road fueling problem!
 

I was thinking about taking the TB spacer off, it didn't add much power wise on a dyno, intrested to know if anyone else thinks the same.

Could the TB spacer cause this problem........

Cheers

Adrian

Re: Off Road fueling problem!
 

Finally a solution to the problem??

Crank angle sensor was failing and giving false readings when getting hot.

Crank angle sensor sends all the info to the engine management unit as to where each piston is and when to put fuel in and ignite that fuel, hence the off road fueling problem.

Re: Off Road fueling problem!
 

That a complicated one! How did you figure out the solution?

Re: Off Road fueling problem!
 

8 months I put up with this problem, progressively it got worse to the point where it would do it on each trip. I spoke to my friendly dealer and said ?Come on guys, come out on a trip with me and bring all your computer test equipment? to be honest they have very little choice but to agree, the H3 had been back and forth and several things where tried. On the trip the problem occurred, they plugged in the test equipment which immediately showed them the error code causing the problem. Checking that error code it was found to be the crank angle sensor which they have now replaced and all is working fine. The problem was each time I had the error, on a straight road the problem would clear along with the error, so each time I took it back to the dealer reporting the fault, the fault code was no longer stored.