ECU engine kill?
Twizted_3KGT
06-18-2007, 01:56 AM
So I was wondering, let's say hypothetically one were to try to race a GTO on the highway and misshift 4th and hit 2nd instead at ~110 mph, one then pushed in the clutch, and the engine died. In this hypothetical situation, does the ECU kill the engine when it sees wayyy more RPMS than it should?
(yeah...i almost shit my pants cuz i was sure I blew my motor or at least jumped the timing belt, had to have been like 12k rpms. First time i ever missed an upshift. Pulled off the side of the highway afraid to restart it, but finally tried and it was all fine)
(yeah...i almost shit my pants cuz i was sure I blew my motor or at least jumped the timing belt, had to have been like 12k rpms. First time i ever missed an upshift. Pulled off the side of the highway afraid to restart it, but finally tried and it was all fine)
Linebckr49
06-18-2007, 10:31 AM
nope, ECU will not kill the engine or limit the revs b/c that's a mechanical over-rev.
when you dropped it to 2nd gear, did you let the clutch out? if so, mechanical over-rev = bad news for your heads. i would seriously not drive the car before you 1) check the timing, 2) leak down test, 3) compression test.
mechanical over-rev usually means bent valves.
when you dropped it to 2nd gear, did you let the clutch out? if so, mechanical over-rev = bad news for your heads. i would seriously not drive the car before you 1) check the timing, 2) leak down test, 3) compression test.
mechanical over-rev usually means bent valves.
Twizted_3KGT
06-18-2007, 08:42 PM
nope, ECU will not kill the engine or limit the revs b/c that's a mechanical over-rev.
when you dropped it to 2nd gear, did you let the clutch out? if so, mechanical over-rev = bad news for your heads. i would seriously not drive the car before you 1) check the timing, 2) leak down test, 3) compression test.
mechanical over-rev usually means bent valves.
Yeah I let out the clutch, I was racing lol, even hit the gas too...only for a split second...the instant I felt myself go forward instead of backward, I slammed the clutch back in and coasted...that's when I noticed the engine had shut itself off. I'm thinking the ECU saw me past redline, cut the injectors, and because I had let off the gas and slammed the clutch in, they didn't turn back on and it just died....unless it has some protective thing that kills the engine when it sees that much RPM.
I thought for sure I had at least jumped timing or seized the motor...but I must have caught it in time, because once I got the courage to try starting it again, it ran just fine. No noises or problems.
when you dropped it to 2nd gear, did you let the clutch out? if so, mechanical over-rev = bad news for your heads. i would seriously not drive the car before you 1) check the timing, 2) leak down test, 3) compression test.
mechanical over-rev usually means bent valves.
Yeah I let out the clutch, I was racing lol, even hit the gas too...only for a split second...the instant I felt myself go forward instead of backward, I slammed the clutch back in and coasted...that's when I noticed the engine had shut itself off. I'm thinking the ECU saw me past redline, cut the injectors, and because I had let off the gas and slammed the clutch in, they didn't turn back on and it just died....unless it has some protective thing that kills the engine when it sees that much RPM.
I thought for sure I had at least jumped timing or seized the motor...but I must have caught it in time, because once I got the courage to try starting it again, it ran just fine. No noises or problems.
Linebckr49
06-18-2007, 09:01 PM
unless you hit fuel cut, but even then i don't think the ECU shuts the engine off, rather the car will just buck violently until you back off the throttle.
still, for piece of mind, if it was me, i would check timing, and perhaps do a compression and/or leak-down test.
still, for piece of mind, if it was me, i would check timing, and perhaps do a compression and/or leak-down test.
youngvr4
06-19-2007, 12:09 AM
yea best thing to do is check things out before you begin to drive it as normal again
Stealthee
06-19-2007, 07:08 AM
There is nothing mechanical or electrical thay would cause teh car to shut itself off. Most likely what happened is when you pressed in the clutch the RPMs fell so fast that the IAC and ECU couldnt catch up and keep the car running.
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