LT1-LT4 Modifications 1993-97 Gen II Small Block V8

Big problem

Old Oct 10, 2010 | 03:37 AM
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Default Big problem

Today I was driving on the freeway in my 1995 z28 when I lost power. First it shut off in traffic, then it just went limp and wouldn't rev above 3000 rpm and I had to floor it to get it to that and off the freeway. I pulled over put some more coolant in it since it sprayed all of it on the side and managed to limp it home. Anyone have any advice on what may have gone wrong here?
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Old Oct 10, 2010 | 05:21 AM
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Did the coolant leak all over the opti spark?
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Old Oct 10, 2010 | 08:35 AM
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Default opti

Originally Posted by LT1
Did the coolant leak all over the opti spark?


That'd be my first guess.
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Old Oct 10, 2010 | 10:42 AM
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The coolant came out after I stopped, I'm just baffled at how I lost so much power all of a sudden.
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Old Oct 10, 2010 | 12:26 PM
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1. overheated
2. limp mode
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Old Oct 10, 2010 | 12:44 PM
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Originally Posted by LSWHO
1. overheated
2. limp mode
Can you explain this in further detail?
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Old Oct 10, 2010 | 12:45 PM
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He can't.
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Old Oct 11, 2010 | 07:38 AM
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Originally Posted by LSWHO
1. overheated
2. limp mode

I'm probably wrong, but isn't that when the pcm is triggered by the car's overheating and cuts power to "avoid" damaging the engine?
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Old Oct 11, 2010 | 08:37 AM
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Originally Posted by RogueLT1
I'm probably wrong, but isn't that when the pcm is triggered by the car's overheating and cuts power to "avoid" damaging the engine?
Good question for LSWHO. If anyone can answer it, LSWHO, Chief of Bad Information Police, can!
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Old Oct 11, 2010 | 09:31 AM
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Originally Posted by SS RRR
Good question for LSWHO. If anyone can answer it, LSWHO, Chief of Bad Information Police, can!
>>>>>>>>WARNING - EXPLANATION AHEAD<<<<<<<<

True limp mode is a PCM condition when the PCM loses most ALL of it's critical inputs. Very rarely does this happen. What most people consider "limp mode" is when one or two inputs are lost and the PCM defaults to a predetermined set of values (either by internal tables or making "educated guesses" from other sensors) for those inputs that are lost - it's basically just guessing. This is not "limp home mode", a term that is grossly overused and mostly misunderstood.
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Old Oct 11, 2010 | 09:51 AM
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Originally Posted by RamAir95TA
>>>>>>>>WARNING - EXPLANATION AHEAD<<<<<<<<

True limp mode is a PCM condition when the PCM loses most ALL of it's critical inputs. Very rarely does this happen. What most people consider "limp mode" is when one or two inputs are lost and the PCM defaults to a predetermined set of values (either by internal tables or making "educated guesses" from other sensors) for those inputs that are lost - it's basically just guessing. This is not "limp home mode", a term that is grossly overused and mostly misunderstood.
lol. Thanks for the warning. You're gonna shock a lot of people by giving an explanation. Thanks for clarifying too, I guess i was sorta right.
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