c4 problems
Thread Starter
Heel & Toe
Joined: Jun 2009
Posts: 20
Likes: 0
From: Ontario
c4 problems
On a hot day after driving my car for about an hour it starts to run bad looses power sputters when you hit the gas peddal. Seems to run fine at night when it is cool out. It's a 1994 coupe. Anyone have any ideas?
Thread Starter
Heel & Toe
Joined: Jun 2009
Posts: 20
Likes: 0
From: Ontario
I have it in the shop now they say tune up and opti, and while they are there waterpump too. I changed the fuel filter last oil change, it does run a little warm tho. Well hope they fix it. Ty for the replies.
Race Director
Joined: Dec 2000
Posts: 17,551
Likes: 26
From: El Paso Texas
They need 3 things to run correctly, and three things only;
1. The correct mixture of fuel and air.
2. A sufficiently strong spark delivered at the correct time.
3. Sufficient compression.
That's it. If those 3 conditions are met, they run correctly. If one is missing or deficient, they either run incorrectly or not at all. Your job is to narrow down which one is the culprit, and then figure out WHY it's the culprit.
We can probably eliminate #3 right off the bat if your car runs fine when it's cold. With bad compression, it either would run poorly all the time or not at all. Which leaves us with #'s 1 & 2. The emissions systems affects both of these as well.
Sooo....it's time to run some tests. Troubleshoot, DON'T GUESS. Don't throw parts ($$$) at the car trying to fix it unless you're independently wealthy and have nothing else occupying your time. If you approach it methodically, you WILL find the problem and be able to rectify it. I've never had one I couldn't get to run correctly.
Let's start with #1. What is your fuel pressure? Check with a guage on the schrader valve. Tape it to the windshield and drive the car. What is the pressure when an event (running poorly) takes place?
Post the results of that test and we will go from there.
1. The correct mixture of fuel and air.
2. A sufficiently strong spark delivered at the correct time.
3. Sufficient compression.
That's it. If those 3 conditions are met, they run correctly. If one is missing or deficient, they either run incorrectly or not at all. Your job is to narrow down which one is the culprit, and then figure out WHY it's the culprit.
We can probably eliminate #3 right off the bat if your car runs fine when it's cold. With bad compression, it either would run poorly all the time or not at all. Which leaves us with #'s 1 & 2. The emissions systems affects both of these as well.
Sooo....it's time to run some tests. Troubleshoot, DON'T GUESS. Don't throw parts ($$$) at the car trying to fix it unless you're independently wealthy and have nothing else occupying your time. If you approach it methodically, you WILL find the problem and be able to rectify it. I've never had one I couldn't get to run correctly.
Let's start with #1. What is your fuel pressure? Check with a guage on the schrader valve. Tape it to the windshield and drive the car. What is the pressure when an event (running poorly) takes place?
Post the results of that test and we will go from there.
