454MPI 330hp repair old EFI, convert to Holley HP or go carburetor
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454MPI 330hp repair old EFI, convert to Holley HP or go carburetor
Need Help with my 97 330hp 454 mpi..
Long story short my ECM thinks my Coolant temp goes from -40 to 180 at random thus flooding the engine. usually when i floor it out of the hole... Been fighting it for years.
my kids are old enough to want to ski and tube so i have to do something...
my options are:
1. find an old ECM and hope its in good condition. I'm also having VST issues now...so that's more money on old stuff
2. convert to Holley HP EFI or something similar, and still have to do something about the VST
3. Convert to a Carb... whats all involved besides intake and the carb,and flame arrestor? Ive had mixed answers on this
any and all help is needed and appreciated here. i'm definitely savvy on wrenching on cars... I'm also familiar with Holley HP EFI since i run it on one of my cars (its pricey though)
Long story short my ECM thinks my Coolant temp goes from -40 to 180 at random thus flooding the engine. usually when i floor it out of the hole... Been fighting it for years.
my kids are old enough to want to ski and tube so i have to do something...
my options are:
1. find an old ECM and hope its in good condition. I'm also having VST issues now...so that's more money on old stuff
2. convert to Holley HP EFI or something similar, and still have to do something about the VST
3. Convert to a Carb... whats all involved besides intake and the carb,and flame arrestor? Ive had mixed answers on this
any and all help is needed and appreciated here. i'm definitely savvy on wrenching on cars... I'm also familiar with Holley HP EFI since i run it on one of my cars (its pricey though)
Last edited by f252br; 06-20-2024 at 04:49 PM. Reason: mis spellings
#2
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If it's a mefi 1it wont be locked (should be since it's a 97) it could simply be programmed to add 0 fuel at -40, when I tune any mefi I always put zero extra fuel in the -40 box anyways as that is ALSO the default it will revert to if connection is lost to ect. I would be inclined to believe you have a loose ect connection or damaged wire in harness as a open ect circuit will plunge the tune into-40. On a mefi 3 it adds 40+% fuel for -40, not many of us get much -40 boating in
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SB (06-21-2024), sutphen 30 (06-21-2024)
#3
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its not the ecu,,its in the ect wiring.
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or,pull the 4 wire plug on the distributor and slap an intake and carb on it.your choose