Cold Start issue on 89GT
#18
Team Owner
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you should be using Bosch silver tips ,
they are about 2.00 each,
part # 7900 Bosch
they are about 2.00 each,
part # 7900 Bosch
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kmascotto (06-04-2023)
#22
Rennlist Member
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I fail to see how a CPS sensor can cause a lean condition but your NBO2 sensor most certainly can.
The male connector on the CPS sensor can and will disintegrate after 15 plus years of service as will the 3 pin male junior powertimer connectors on the Hall Trigger, the knock sensors and the idle switch connector. Why this happens when the female connector it slides into invariably is perfectly OK fascinates me given I have no answer for this phenomena. One might think the male connector would be more protected.
The male connector on the CPS sensor can and will disintegrate after 15 plus years of service as will the 3 pin male junior powertimer connectors on the Hall Trigger, the knock sensors and the idle switch connector. Why this happens when the female connector it slides into invariably is perfectly OK fascinates me given I have no answer for this phenomena. One might think the male connector would be more protected.
#23
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Hi Fred, as you suggested, I replaced the NB02 because as you noted, its the most likley reason why the A/R is off...but it didnt make a difference.
I will say that first noticed the change in the A/F after adding fuel injector cleaner (I may have been a little to generous with the fluid) Ive since emptied the tank and refiled the car with fresh premium fuel. Currently at idle, its hovers around 16.5, at about 2500rpm if around 14.7...so thats good.
I'm still dumbfounded as to why the car won't go through the cold start high idle process.
I will say that first noticed the change in the A/F after adding fuel injector cleaner (I may have been a little to generous with the fluid) Ive since emptied the tank and refiled the car with fresh premium fuel. Currently at idle, its hovers around 16.5, at about 2500rpm if around 14.7...so thats good.
I'm still dumbfounded as to why the car won't go through the cold start high idle process.
#24
Rennlist Member
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Hi Fred, as you suggested, I replaced the NB02 because as you noted, its the most likley reason why the A/R is off...but it didnt make a difference.
I will say that first noticed the change in the A/F after adding fuel injector cleaner (I may have been a little to generous with the fluid) Ive since emptied the tank and refiled the car with fresh premium fuel. Currently at idle, its hovers around 16.5, at about 2500rpm if around 14.7...so thats good.
I'm still dumbfounded as to why the car won't go through the cold start high idle process.
I will say that first noticed the change in the A/F after adding fuel injector cleaner (I may have been a little to generous with the fluid) Ive since emptied the tank and refiled the car with fresh premium fuel. Currently at idle, its hovers around 16.5, at about 2500rpm if around 14.7...so thats good.
I'm still dumbfounded as to why the car won't go through the cold start high idle process.
Suggest you check your temp2 sensor resistance values when cold- should be around 3k to 4k ohms as I recall dropping to about 200 ohms when warmed up. Check both channels pin to earth
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kmascotto (06-05-2023)
#25
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Honest question for the good wrenches here: why not check the ISV, in this case? Prior to the lean condition, that's where my thoughts went but I'm looking to learn and improve my diagnostic skills.
Good luck OP, you've got the Wolves helping your shark.
Cheers
Good luck OP, you've got the Wolves helping your shark.
Cheers
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kmascotto (06-05-2023)
#26
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#28
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The input info was difficult cold starts and the revs were not picking up- this to me suggests the brains are not being told the engine is cold thus the difficulty becuase it will not be getting cold start enrichment.
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Zirconocene (06-05-2023)
#29
Team Owner
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in the CPS picture what is the wire thats wrapped with tape or silicone wire wrap?
A knock sensor wire?
A knock sensor wire?
#30
Rennlist Member
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A dead WOT switch will not trigger the WOT enrichment map.
Check your WOT Switch
Peruse here:
https://rennlist.com/forums/928-foru...itch-help.html
Check your WOT Switch
Peruse here:
https://rennlist.com/forums/928-foru...itch-help.html
Last edited by Shirah; 06-06-2023 at 06:33 PM.