91 sse cutting out when cold- runs fine warm!

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pbgunrunner
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Posts: 3
Joined: Sat Dec 13, 2014 5:40 pm
Year and Trim: 1991 SSE

91 sse cutting out when cold- runs fine warm!

Post by pbgunrunner »

OK, this would seem to be an easy one right? the two wire temp sensor- but it wasnt! So, heres the symptoms-

When its cold (sub 50) out the car starts fine. a few seconds later (assuming when it starts to read the sensors) it starts to cut out and run like crap. the service engine light and the small temp idiot light will both "flicker" on and off. it acts almost like the ignition is getting turned off and on, and theres a very strong gas smell. Going down the road it will hesitate and buck and act like it has a strong miss. Once its warmed up i can shut it off and turn it back on and itll be ok for the rest of the day or until it gets really cold again. it did this at the end of last winter, but not during the hot summer months.

So far Ive replaced the maf, the crank sensor, the two wire temp sensor and cleaned out the egr. if i unplug the o2 sensor and put it into the service mode it runs just fine. Im open to suggestions here!!! Im going to go out and try to pull the codes in a few min, ill advise what i find.

Please save me and my bonnie! if i cant get it fixed in going to invest in a gallon of gas and a book of matches!! :angry4:
pbgunrunner
LE Member
Posts: 3
Joined: Sat Dec 13, 2014 5:40 pm
Year and Trim: 1991 SSE

Re: 91 sse cutting out when cold- runs fine warm!

Post by pbgunrunner »

Also- the service engine soon light and the temp idiot light will continue to randomly flash when the key is in the "run" position, even when the engine is not running. Once they stop the "spluttering flashing" the car runs fine. I've also replaced the IAC valve...
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MattStrike
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Re: 91 sse cutting out when cold- runs fine warm!

Post by MattStrike »

Unplug the o2 sensor and it works fine: My '89 does the same thing. I would start by replacing the O2 sensor. I haven't really dug into the issue on mine yet.
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pbgunrunner
LE Member
Posts: 3
Joined: Sat Dec 13, 2014 5:40 pm
Year and Trim: 1991 SSE

Re: 91 sse cutting out when cold- runs fine warm!

Post by pbgunrunner »

I'm not sure if the o2 sensor is the issue though or if it being unplugged just throws it into the non sensor mode?
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