BatmanLS1

I own a 1994 Regal 3800 w/ 115,000 miles.

When I bought it a year ago, I noticed on the highway that it would have a slight miss when going down the road at a steady 65- 70 mph. It would just feel like the car was hesitating for a fraction of a second...not all that bad.

Well, a year later it's still there, but getting much worse and much more frequent. As soon as the car shifts into overdrive (at any speed), within a few seconds the car will start stumbling. The RPMs stay steady on the tach, but the car kinda shakes and feels like it's missing (not accelerating).

This has been going on for a month, and I could usually get the car to quit doing it by making it downshift back into 3rd. Now, it is starting to miss while I accelerate in any gear. The rpms still climb, but it's like something is telling the car to go/not-go 100 times per second when I try to accelerate.

The car starts on the first try everytime and idles fine. I have done some basic things like spark plugs and PCV valve. A year ago, the water pump was replaced by a mechanic (before I owned the car). I'm just not sure whether this is a sensor (crank, cam, other), the pcm, or fuel related.

Any help is appreciated. I would like to keep the car, and I don't want to just throw parts at it.

Thanks.

dmhoo29

Look to see if the plug wires are the originals. If so,that is probably your prolem.

My car did the same thing,and after changing the plugs it still did it,then i changed the plug wires and it was my plug wires.

Next ,try the fuel filter.These are the cheaper trials and errors.lol

GOOD LUCK
Let me know what you find.

88Regal Custom

my car also did something like that,
it ended up being the catilitic converter was getting plugged until the morning i could not get it past 20 MPH with it floored!

brunnj

I agree. I had the same problem with my wife's Regal. I put new plugs in it and it started to miss. I found two things. One, I put Bosch Platinum plugs in hers. I pulled them all back out and rechecked them. On two of the plugs I noticed the tip was loose. I tightened them and reinserted them. I then looked at the plug wires and saw lots of carbon deposits where they connected to the plugs. I replaced the wires as well and her miss has gone away. Hope yours ends up being a cheap and easy fix.

BatmanLS1

Replaced the fuel filter - no change.

Changed plugs back to platinums and changed the spark plug wires. All is well.

It appears one of the spark plug wires was not original (no cylinder # on it and it was way too long...went to cylinder #2). My theory is this one was the culprit b/c I changed the front 3 (1,3,5) first and I still had the problem. Then did the back ones (2,4,6) and it's all fixed. This wire also did not have the plastic cover thing the other 2 had where it runs across the engine. I will try to get one as this may have led to it breaking down.

It's been a while since the Regal ran this smooth.