I have a very serious problem with H2 engine shutting down while driving on the freeway. Once it shuts down, I pull over and I can start the engine right away. The shutdown is random. This is a 2003 H2, original owner, low mileage. First time the shutdown occurred was about a year ago. I had it checked by the dealer. Of course, it behaved when the dealer had it for a week of testing. They ended up replacing the main computer. But the guy said this issue may be an additional problem (of course) and that the computer was bad anyway!

Since then, I have replaced the spark plugs, fuel filter and lately one very confident mechanic swore that the problem was the faulty idle box. We replaced that as well. None has fixed the problem as it shut down again a couple of days ago. Does anyone have any solution to this problem? I appreciate any help I can get.

 

I think I'd be looking for a faulty ignition switch..........

 

I've heard of this happening on other vehicles where the cause was the transmission control unit, speed sensor, or transmission pressure sensor.

 

Cam shaft sensor, ignition switch, mass air flow meter. I had a Corvette once (was a 1989). Engine would just shut down. Same thing restart no problem. Turned out it was a Mass airflow meter.

 

have you had it scanned recently ,if so what were the codes. the check engine light does not have to be on to store a code.

 

Thank you for the quick reply. I will pursue this one as it may be the cause.

 

I had it sacnned the first time when they replaced the main computer. Apparently, there were a few error codes. I have not scanned recently but I am taking the H2 in for a scan.

 

I will check these if the ignition switch idea doesnt work.

 

Anyone help i know this os super old but im having this issue now i plugged the pc and it said the main computer the trannny compyuter n the fuel computer hep i dont want to start changing computers and end up being something else

 

I could try to help but not sure what you mean. Plugged pc? Main comp, trans comp, fuel comp hep? Not sure what your getting at here.