Unsolvable Misfiring Problem

[Eidolon]

I have a stock 92 Talon 2.0L N/T with an automatic and 130k miles. When I'm heavily accelerating, especially after downshifting from 3rd or 4th back to 2nd the car hesitates for a moment and I can feel the car lose power, the Check Engine light comes on and then it suddenly bucks forward again for just a second. Its worst in 2nd gear, then gets better as it keeps shifting up, and sometimes the symptoms clear up if you continue accelerating. When I stay cruising it'll keep its speed except every few seconds it gives a quick buck or two. When decelerating the Check Engine light stays on and the car shakes. When I come to a full stop and try to idle the car shakes and struggles to keep from stalling, or just plain stalls. 90% of the time it only happens once the car is fully warmed up and I can usually reproduce the problem if I try. I'm also getting pretty poor gas mileage and it can be a pretty poor shifter. The problem seemed to go away after my Power/Economy switch became disconnected while I was detailing the center console but came back a month or two later. I've been trying to solve the issue and so far I've changed the spark plugs+wires, and found out that my thermostat, o2s, and coolant sensor needed replacing. At one point I thought it may have been carbon deposits from running 93 octane (using only 87 again) so I also cleaned the cylinders and then I cleaned the MAF after reading up on it. I'm planning on inspecting the ECU and ignition coils next but I need to know if there's anything else I missed that could be related to this problem. I've wanted to do some basic mod's to it, but I'm not going to bother until it runs right first. Thanks for your help.

 

[BISHILVR]

What code is the ecu setting? Check fuel pressure?

 

[Kloopofadown]

Sounds allot like my MAF sensor when It had BOTH honeycombs removed. Does it idle better when you unplug the MAF sensor?

 

[BISHILVR]

Also check for oil down inside of the spark plug wells, if you have oil on your plug boots they will misfire. The n/t 4g63 tends to ping also, when that happens the plugs will misfire under a load even though they look fine. Try replacing them again and see if it goes away for a while.

 

[sytrus]

Well I have had a similar problem to this one, and I replaced the plugs and i continued... I know this sounds stupid... but make sure your battery terminals are cleaned and tightened, this sounds exactly like what happened to me about a year ago. Hopefully this is the cause, because it's an easy fix... and it should be done anyway. Other than that as previously mentioned make sure you don't have any oil by your plugs.

 

[Eidolon]

Well, I want to thank everyone for your advice but I have some horrible news. My 92 was totaled today. A woman in a Camry pulled out in front of me while I was heading to the junk yard. The front end of the frame is gone. Thankfully everyone was alright, and it wasn't my fault. I'm considering getting either another 1g or a 3000GT next. I'll get a few photos later.

 

[spyderturbo007]

Sorry to hear about the car, but at least you are ok