Would shorted sensor wires cause me to stall?
Thread Starter
Cruising
Joined: Mar 2020
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Would shorted sensor wires cause me to stall?
My 96 auto used to run nice and strong up until two weeks ago. I had a coolant leak earlier, so I thought the opti had offed itself.
when I put in a new one in, I tested it before reinstalling the wp and it fired right up. Once I had everything assembled back to normal, it wouldn’t start.
there’s three sensors that were unplugged when it started; the MAF, IAT, and coolant temp. I tried unplugging one at a time and then the different combinations of two at a time. I found that my car starts and runs when the temperature and IAT sensors are unplugged.
What do you guys think causes this? Did the harnesses go bad between the two and are now shorting out?
when I put in a new one in, I tested it before reinstalling the wp and it fired right up. Once I had everything assembled back to normal, it wouldn’t start.
there’s three sensors that were unplugged when it started; the MAF, IAT, and coolant temp. I tried unplugging one at a time and then the different combinations of two at a time. I found that my car starts and runs when the temperature and IAT sensors are unplugged.
What do you guys think causes this? Did the harnesses go bad between the two and are now shorting out?
Team Owner
Joined: Sep 2001
Posts: 62,119
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From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
The computer relies heavily on Coolant temp and MAF readings to do the A/F in open loop operation, which is immediately at startup. If all 3 are messed up somehow, I wouldn't be surprised that it won't run well at all.
Team Owner
Joined: Sep 2001
Posts: 62,119
Likes: 1,725
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
Thread Starter
Cruising
Joined: Mar 2020
Posts: 11
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So I've replaced the two sensors in question, but to no avail. I have also looked at the pcm wiring diagrams and they don't seem to have any common connections.
Did the summer heat melt any wires? On the day it died, it had a really hard start and would miss when I stepped on the gas pedal. I managed to limp it home after work but it didn't turn on afterwards.
Did the summer heat melt any wires? On the day it died, it had a really hard start and would miss when I stepped on the gas pedal. I managed to limp it home after work but it didn't turn on afterwards.
Thread Starter
Cruising
Joined: Mar 2020
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Okay so with the engine running, I tested the two sensors with a paper clip.
When I closed the circuit on the coolant lead, the engine kept running but the idle speed was no longer constant. When I closed the IAT circuit, the engine very quickly stalled.
what does this mean? I don’t know what to make of my results
When I closed the circuit on the coolant lead, the engine kept running but the idle speed was no longer constant. When I closed the IAT circuit, the engine very quickly stalled.
what does this mean? I don’t know what to make of my results
