Engine cold:Runs great Engine warm: not so much
Thread Starter
Pro
Joined: Mar 2004
Posts: 654
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From: Linthicum MD
Engine cold:Runs great Engine warm: not so much
Friend of mine has a '92. When the car is cold, it runs great. Full throttle/part throttle, doesn't miss a beat. When it warms up, it stumbles under load and dies while driving. Funny thing is it will start back up every time with hardly any cranking.
The car will still run rough with some black smoke coming from the exhaust and he will have to limp home. When it cools down, its fine.
I haven't had that problem with mine. Has anybody here had problems like this and what was the solution.
In the last 3 years he has replaced:
Spark plugs
wires
coil
map sensor
injectors
o2 sensors
He's getting fuel pressure. 42psi when I checked it.
The car will still run rough with some black smoke coming from the exhaust and he will have to limp home. When it cools down, its fine.
I haven't had that problem with mine. Has anybody here had problems like this and what was the solution.
In the last 3 years he has replaced:
Spark plugs
wires
coil
map sensor
injectors
o2 sensors
He's getting fuel pressure. 42psi when I checked it.
Melting Slicks
Joined: Oct 2006
Posts: 2,238
Likes: 10
From: College Station TX
Sounds like something is going bad when it hits closed loop. Could be an O2 sensor, or another senor feeding the computer bad data. I would start by driving it with a scanner hooked up and see what is happening when it starts running bad.
Last edited by Mojave; May 30, 2009 at 10:22 PM.
Thread Starter
Pro
Joined: Mar 2004
Posts: 654
Likes: 18
From: Linthicum MD
The sputtering will start after the car has been running for about 10 minutes. The sputtering only happens under load and is VERY harsh. It seems like the engine is being flooded with fuel.
Melting Slicks
Joined: Dec 2008
Posts: 2,772
Likes: 64
From: Mystic CT
The only thing of any consequence that changes in ten minutes is going from open loop to closed loop. Only 2 things that would make a big difference is bad O2 sensors or coolant temp sensor. My bet is with the scanner you will see very few O2 sensor cross counts and a very lean reading from the dead sensor that may or may not be dead enough to throw a code. If you disconnect the O2 sensors it should throw a code and go back into open loop.. Worth a try I would think. If a coolant sensor it is coorect with a cold engine but wrong with a warm one adding un-needed fuel scanner will show this as well.
Dave
Dave
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Pro
Joined: Mar 2004
Posts: 654
Likes: 18
From: Linthicum MD
My friend informed me this morning that his coil that he had bought 3 years ago is a cheap jegs model
. All of his symptoms would match up with that(I hope its that simple).He just bought the o2 sensors last year.
Would a bad coolant temp sensor really cause the car to basically shut down when under load?
. All of his symptoms would match up with that(I hope its that simple).He just bought the o2 sensors last year.Would a bad coolant temp sensor really cause the car to basically shut down when under load?
