Acceleration problems

[Dan94Z34]

I have an 89 Regal 3.1 auto. I went to the store today and noticed, once you gave it over 1/2 throttle it simply would cut out like it was dead. If you let off the gas, and give it 1/4 throttle it will accel. It has no codes stored and the fuel pressure is good. If you sit in park and rev it, it revs just fine with no hesitation. I also noticed it is now leaving puddles of trans oil the size of a silver dollar where ever I park at. I checked the tans oil, and it is with in the operating range. Any ideas?

[Dan94Z34]

I also checked all the fuses under the hood and fuse panel inside, and found none of them blown.

[Crazy K]

sounds like you have a bad TPS sensor. try unhooking it and see if the car responds the same.

 

try to isolate the leak. major areas could be typical culprits in likely order:

pan gasket

cooling line hoses

either axle seal

I also saw a chysler once that had a leak at the base of the dipstick...

 

 

 

[Dan94Z34]

I unpluged the TPS and drove it around the block. It does the same thing only worse now. Would that confirm the TPS is bad?

[jman093]

I unpluged the TPS and drove it around the block. It does the same thing only worse now. Would that confirm the TPS is bad?

 

No, it means that isn't the problem if it does it with the it unplugged. You might try the same thing with the MAP sensor unplugged and see if that doesn't get rid of the problem, but I would guess a bad coil pack or ignition module. Can provide spark under light loads (less than half throttle and in park), but not when there's a lot of load (over half throttle).

[jtwmechanic]

do you have any codes stored. is your check eng light on. you will probally want to reset the the ecm because you have unplugged sensors which will throw codes. so reset the ecm and drive the car. hopefully it will throw you a code to help track down your problem.

[Dan94Z34]

I did have a problem with it misfiring badly under load last winter. That ended up being two bad coil packs and a bad ICM. I put two new coil packs and a used ICM in it and it solved that problem. My bee the used ICM decided to go south?

 

I went out for another test run tonight. It accelerates normally to about 2800-3000 RPMS and then its like hitting a brick wall. If I hold the foot feed steady after it "hits the brick wall", it will try to accel. for a sec, then cut out, try to accel for a sec. cut out, etc. When its doing this the car is also real jerky.

 

I checked the computer for codes again, and there were none stored. The SES light hasn't come on at all during this ordeal. I will try unpluging the MAP sensor and see if that does any good. I do have another ICM laying around in the garage that came off a running car. I could try swaping it and see what it does too.

 

 

[jman093]

I did have a problem with it misfiring badly under load last winter. That ended up being two bad coil packs and a bad ICM. I put two new coil packs and a used ICM in it and it solved that problem. My bee the used ICM decided to go south?

 

I went out for another test run tonight. It accelerates normally to about 2800-3000 RPMS and then its like hitting a brick wall. If I hold the foot feed steady after it "hits the brick wall", it will try to accel. for a sec, then cut out, try to accel for a sec. cut out, etc. When its doing this the car is also real jerky.

 

I checked the computer for codes again, and there were none stored. The SES light hasn't come on at all during this ordeal. I will try unpluging the MAP sensor and see if that does any good. I do have another ICM laying around in the garage that came off a running car. I could try swaping it and see what it does too.

 

 

 

O'reilly or Autozone has a machine to test the ICM as well. Does it need a tune-up? Worn plugs will keep killing an ICM. I kept ruining ICM's every few months on the Lumina and thought the plugs had been changed, but it turned out my dad had only changed the fronts since the rears were a pain. After I realized that and changed all the plugs it's been fine.

[Dan94Z34]

I have an O' Reilly in town. I will take the ICM off tomorrow and have it tested. The plugs and wires were replaced last summer.

[GOT2B GM]

Clogged cat made those exact symptoms on the old 87 Z24 with a 2.8.

[ns87]

For me, it was always a popped off/broken vacuum line at either of those sensors at the top-back of the engine

[Dan94Z34]

OK, I swapped the ICM with my spare, and still have the same problem. I checked the vacuum lines, and they are all connected. I did notice when I started it up cold this morning, there was a rattle from the exhaust. It maybe a clogged cat. I will have to jack the car up and see.

[BXX]

Injectors.......

 

Ohm them, find the bad ones, replace, and enjoy!!

[Dan94Z34]

I took the cat converter off the car. The stuff inside the cat was loose and rattling around. I test drove the car again, the car runs better, but does the same thing, only it does it around 4K rpms now. I think an exhaust restriction was a part of it, but there is still something else wrong.

 

I checked the two fuel injectors I can get to without pulling the upper intake off. The one in the front left was at 8.1 Ohms, and the other at the back right was at 13.2 ohms. I think I may have found the problem. bad fuel injectors, well at least one bad one. Looks like I'm going to have to pull the upper intake and check the rest now.

[BXX]

ZING!!!

 

I win...

 

8.1ohms is definately bad... Be prepared to have more than 1 bad though

[Dan94Z34]

Does anyone have any spare fuel injectors they would want to part with?

[AL]

I have some from a 98 3800 S2 with 44k... I dont know what they are worth tho.

[Dan94Z34]

Will injectors from a 3100 work? I found a set at my local wrecking yard for cheap.

[Crazy K]

I have some from a 3.1 I have enough for a matched set, and I will OHM check them.

[DavidHowell3633]

There may be one other check to make. I had similar missing/stumbling upon accelration last week. It was corroded spark plug wires at the plugs. Hope this helps.

[Dan94Z34]

Plugs and wires were already checked. Thanks for the suggestion though.

[88Regal Limited]

I have an 89 Regal 3.1 auto.

I FOUND YOUR PROBLEM!

 

My ICM did the exact same thing when it was dying, and so did a burnt plug wire.

 

Injectors would cause the same thing though.

[BXX]

 

 

I checked the two fuel injectors I can get to without pulling the upper intake off. The one in the front left was at 8.1 Ohms, and the other at the back right was at 13.2 ohms. I think I may have found the problem. bad fuel injectors, well at least one bad one. Looks like I'm going to have to pull the upper intake and check the rest now.

 

 

I have an 89 Regal 3.1 auto.

I FOUND YOUR PROBLEM!

 

My ICM did the exact same thing when it was dying, and so did a burnt plug wire.

 

Injectors would cause the same thing though.

 

 

[Dan94Z34]

Crazy K set me up with a set of fuel injectors. Hopefully they come in the mail tomorrow, so I can get this thing running correctly again.

[Dan94Z34]

The car is fixed. It ended up having three bad injectors.