open loop (idiot mode)
02-26-2008, 01:13 AM
#1
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open loop (idiot mode) what sensors/problems would cause my car to run in limp home mode after a stall?
ive replaced :
MAP sensor
coil
ICM
IAC
plugs
wires are new except one of them is heat cracked
fuel filter is fairly new but not hung on its clamp
TPS is about 8-10 months old
i cleaned the MAF because i had a K&N
EGR is new but im starting to wonder about the solenoid
im stumped. i swapped out my O2s (bosch) for my old oem ones that were sitting and it still stalls right after start up/once every drive cycle at a random idle. also the starter started grinding and spinning freely sometimes after this
it goes into limp home mode and ive been driving it like this for weeks.
could the battery being 7 years old and still holding 13 volts cause it? i heard the ampage could diminish after a few years.
or the VSS?
coolant temp sensor?
ive replaced :
MAP sensor
coil
ICM
IAC
plugs
wires are new except one of them is heat cracked
fuel filter is fairly new but not hung on its clamp
TPS is about 8-10 months old
i cleaned the MAF because i had a K&N
EGR is new but im starting to wonder about the solenoid
im stumped. i swapped out my O2s (bosch) for my old oem ones that were sitting and it still stalls right after start up/once every drive cycle at a random idle. also the starter started grinding and spinning freely sometimes after this
it goes into limp home mode and ive been driving it like this for weeks.could the battery being 7 years old and still holding 13 volts cause it? i heard the ampage could diminish after a few years.
or the VSS?
coolant temp sensor?
Last edited by Revelation Z28; 02-26-2008 at 01:21 AM.
02-26-2008, 02:35 AM
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no, whatever is causing this is making the car switch back into open loop when it tries to go to closed. but only if i drive it. cold start it wont die no matter that i do, only if i drive.
02-26-2008, 03:07 AM
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Open Loop is NOT Limp Mode. Unless they changed how Limp Mode is after 93 . . . Limp mode is your car is LITERALLY limping. You can't give it gas with out it falling on it's face. Imagine breaking both legs, and crawling home by dragging yourself with your arms. That's the equivalent 
Anyways, a bad PCM/ECM is what'll throw a car into Limp Mode. On an ECM, remove the whole EPROM and you'll see what Limp Mode is all about.
That one wire could be bad, not sure. The starter sounds like it's got it's own gremlins, and the battery SHOULD be fine, but it shouldn't have 13vs. I think they're 12.4v. So, alternator could be overcharging. It'd have to be way overcharging I'd think to throw the whole system out of whack.
Anyways, a bad PCM/ECM is what'll throw a car into Limp Mode. On an ECM, remove the whole EPROM and you'll see what Limp Mode is all about.
That one wire could be bad, not sure. The starter sounds like it's got it's own gremlins, and the battery SHOULD be fine, but it shouldn't have 13vs. I think they're 12.4v. So, alternator could be overcharging. It'd have to be way overcharging I'd think to throw the whole system out of whack.
Last edited by Formula350; 02-26-2008 at 03:12 AM.
