Car has a miss, can anyone help me figure out the reason?

[ceecee8384]

Hi everyone, I have a 1995 Chevrolet Corsica, 4 cylinder. When it idles, there's a miss, and when I am trying to go up hills, the car loses power no matter how fast I go to try to get up it, I usually bottom out at about 20 miles per hour. I have replaced the head, coil packs, spark plugs and wires a couple time, oxegon censor mass air flow censor, etc etc in censors, also I have replaced the fuel filter, checked compression it was fine. Is there something I'm missing here? The car does have 239,000 miles on it and starts right up, never given me a problem. I just don't understand why it is still missing and has no power going up hills. I tried to take it to autozone to see if the could hook it up to a computer to see if it threw any codes, but of course my car is too old. Any ideas would be greatly appreciated.

[jsgold]

Did you have the ignition module checked when replacing the coils? The coils you installed were new I assume also. Only other thing that comes to mind would be plugged injectors.

[Airjer_]

Plugged cat. Drop the exhaust from the manifold and take it for a drive.

[ceecee8384]

Originally Posted by jsgold

Did you have the ignition module checked when replacing the coils? The coils you installed were new I assume also. Only other thing that comes to mind would be plugged injectors.

The coils were brand new that I purchased from the dealer. I used the fuel injector cleaner, should I just purchase new injectors or should I just try to clean them again?

[ceecee8384]

Originally Posted by Airjer_

Plugged cat. Drop the exhaust from the manifold and take it for a drive.

The car missed while idling, would that still be a plugged cat? I was told that if it missing while idling it couldn't be a plugged cat.

[Airjer_]

Two ways to check. Drop the exhuast or check backpressure.

Does it have a vacuum EGR or electric. If its vacuum what happens when you disconnect the vacuum hose.

[ceecee8384]

Originally Posted by Airjer_

Two ways to check. Drop the exhuast or check backpressure.

Does it have a vacuum EGR or electric. If its vacuum what happens when you disconnect the vacuum hose.

How do I check the back pressure? It has vaccuum, and I am pretty sure when it was disconnected, it cut out.

[captan]

I have an 89 buick I have had problems of stalling when coming to stop signs or when I let my foot off the gas in turning a corner. It got really bad cause I would loose power steering in the middle of a turn. I checked everything. Cleaning the throttle throat and making sure no codes were present. It was driving me crazy!! I filled the tank with (white from US GAS Station) gas and used high test 93 octane. The first tank it stalled a couple of times. The second tank it has not stalled at all. It runs better, no more stalling and gets better take off. I always bought gas at the same place used regular. I won't buy from my old gas station again. Gas does make a difference!

[ceecee8384]

Ok, so the car is still having the miss. The cat coverter was taken off, hollowed out, and still has a miss!! Now, when going up a hill it pops and sounds like it's back firing through the intake. Guess I'm going to have the put new injectors in or maybe buy a new car Any other ideas before she goes to the junk yard?

[Airjer_]

I wouldn't bother with the injectors. If you can hear it popping through the intake than there is probably a timing issue. Are you sure you have the wires going to the correct cylinders?

[ceecee8384]

Yes, the firing order has been checked. I also replaced the timing chain and gear a few months ago. Forgot to add that to the parts that were changed. It was one of the original ideas we had come up with that was wrong with it. The old timing chain and gear we took off was perfectly fine. If it isn't timing chain and gear, plugs, wires, coil pack, what else could it be?

[ceecee8384]

Also, I forgot to mention did the entire fuel injector cleaner thing again, no change. My dad took it for a drive so I could show him how bad the car is running, and he put it down in 2nd to see if it would gain speed, the engine just roared. He said maybe it's starving for gas. We changed the fuel filter before. I was told if it's the fuel pump, it wouldn't start at all. I think it's just time to retire it. 2 mechanics can't figure out what's wrong with and I've picked tons of online brains, and nothing.