Running poor when cold
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Running poor when cold
Hi. New user here. I have a 1986 F150 5.0 auto overdrive that has a cold running problem. I have just replaced the timing chain. In the process the following parts were replaced. Plugs,wires,cap,rotor,Ignition module and fuel pressure regulator.The problem is when the truck is cold it will start right up and run about 30 seconds and then shut off. It restarts fine. If you goose it and let it build a little temperature it runs fine. When it is warming up seems to be running rich. Once it is warm truck purrs like a kitten. Truck has 92,000 miles on it. No codes are showing. Could the computer be in closed loop when cold then fine when warm?
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From: Virginia
Running poor when cold
Here's a shot in the dark if you don't have any codes. There are some guys on here from time to time that have been having problems with intake plenum gaskets leaking on the 5.0 fuel injected truck engines. Maybe yours is leaking air, and then as it warms up, the casting swells a little and it seals off.
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Running poor when cold
Steve:
Funny you should ask. I inherited the truck from my father. I checked the check engine ( emission on this truck) . I found someone cut the light socket out. Only 2 wires left. However, I had a scan tool on it a couple of weeks ago and it did not come up with anything.
Funny you should ask. I inherited the truck from my father. I checked the check engine ( emission on this truck) . I found someone cut the light socket out. Only 2 wires left. However, I had a scan tool on it a couple of weeks ago and it did not come up with anything.
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Running poor when cold
Dave F:
I just went thru the intake gasket on the 250. I have checked all sensors and vacumn lines. I did notice something this morning though. Just after I started the truck I accidently hit the turn signal. Nothing. After the truck warmed up a couple of minutes the turn signals worked. Will dig deeper this weekend I hope.
I just went thru the intake gasket on the 250. I have checked all sensors and vacumn lines. I did notice something this morning though. Just after I started the truck I accidently hit the turn signal. Nothing. After the truck warmed up a couple of minutes the turn signals worked. Will dig deeper this weekend I hope.
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Joined: Nov 2002
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From: Memphis, TN
Running poor when cold
Originally posted by groots
scan tool on it a couple of weeks ago and it did not come up with anything.
scan tool on it a couple of weeks ago and it did not come up with anything.
Did the scantool's light not come on at all? 
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Running poor when cold
Steve:
Did not have access to scanner tool. Pulled codes with a volt meter KOER. Here is what I got 24-41-77-25 and then they repeated.If I read them right 24 is IAT, 25 is knock sensor, 41 is
system lean, and 77 system did not receive goose pulse. Does any of this make sense?
Did not have access to scanner tool. Pulled codes with a volt meter KOER. Here is what I got 24-41-77-25 and then they repeated.If I read them right 24 is IAT, 25 is knock sensor, 41 is
system lean, and 77 system did not receive goose pulse. Does any of this make sense?
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Post Fiend
Joined: Nov 2002
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From: Memphis, TN
Running poor when cold
25 & 77 are operator error - you're supposed to stomp the gas & do something to trigger the KS, but you'd have to read the Haynes for specifics.
The ACT (IAT) could be bad causing the lean condition, but you should test them all with a multimeter according to Haynes.
So why did you say you got no codes?
Here's my code list.
The ACT (IAT) could be bad causing the lean condition, but you should test them all with a multimeter according to Haynes.
So why did you say you got no codes?
Here's my code list.
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Running poor when cold
Steve:
When I originally posted one of my friends stopped with his scan tool. We hooked it up and it did not show any codes. Maybe the tool had a problem. that is why I tried to puul them with a meter. Will look into the manual for the testing.
Thanks!!
When I originally posted one of my friends stopped with his scan tool. We hooked it up and it did not show any codes. Maybe the tool had a problem. that is why I tried to puul them with a meter. Will look into the manual for the testing.
Thanks!!
