Question Asked: Engine stops running abruptly at about 2,000-2,500 rpm.
August 19, 2010, 03:03 PM
The problem began after the engine was replaced with a lower mileage, used engine (punctured radiator from highway debris caused it to overheat and warp). A couple of weeks after the replacement, it stalled on the freeway without warning. Now it will start and run until the speed reaches about 2,000-2,500 rpm. Then it just quits, like the key had been turned off. It will immediately restart and do the same over thing again. Sometimes the check engine light will come on, sometimes it will flash, sometimes it will not come on at all. The mechanic who replaced the engine checked the throttle position sensor, plugs, wires, injectors, distributor, put at least two or three different used ECM's in and did everything else he could think of (including consulting other mechanics) and finally gave up. Fortunately he didn't charge anything since he didn't fix it. Took it to the GM dealer who replaced the fuel filter and said there is good fuel and spark but the ground on the ECM is lifting right at the point the engine quits and wanted to replace the ECM again and rewire it. Unless I am missing something, I would think that the wiring should be OK if it runs consistently at the lower speed and never cuts out until the engine speed is increased. Any thoughts or suggestions would be appreciated.
Question Asked: Engine starts but won't accelerate
January 25, 2010, 10:13 AM
The engine quit without warning on the freeway and now will start and idle but dies as soon as the accelerator is pressed. Diagnostic code shows a bad ignition module and main computer but replacing them makes no difference. We have had it to two different shops and both are stumped. The original engine blew a head gasket and was replaced with a lower mileage but identical engine about six month ago. Compression, plugs, etc. all check out OK.