96 Grand Am Quad-4 Bucking

[odmbc3]

Here is the problem...when I get up to speed and I'm just off the gas and cruising at about 45-50MPH the car starts bucking and spitting. Press on the gas it goes away or drop down into 3rd goes away. Had it to a mechanic and put on computer said the car has misfired at least 6000 times in its life of which 3000+ were from the 4th cyl. Had fuel cleaner system blown through and replaced the castle and plugs. Short term fix for the problem, now it is back to doing the samething. Any clues as to if it is a tranny problem or injector problem or something else. Thanks for the help.

[Scrapper]

could be injector..have you pulled the plugs out and see if there black?? if burning to rich they will turn black...i'd try some sea foam before injector to make sure it dosn't have moister in gas if not i'd change filter first..good luck..

[skibum1111]

With a misfire situation you have either a bad plug, plug wire (looks like a little boot that goes from the coil pack to the plug), coil or coil housing, or a bad ignition module. I'd start with the plugs and wires, and while you have the coils off check for carbon tracks. I had a bad coil cover on my 95 quad, didn't find it until I had the cover off checking spark and one of my friends happened to see it arcing to the top of the motor. Good luck.

[odmbc3]

Well so far I have replace the ignition coil housing and plugs before and it happen again. Started bucking and sputtering to the point it wouldn't go over 10mph. Checked the plugs and they were fine no carbon build up, replaced the ignition coil housing since it was under warrenty from the last time. Also when this happens the check engine light comes on and the ETS Off light comes on. Which means I don't have Electronic Tracking System working correct. So does this mean that the bucking and sputtering that happens at 45-50 mph have something to do with the transmission. I have looked at other forums and have seen that it may be torque conveter or maybe even EGR valve. Thanks for the input so far Scrapper and Skibum1111, much appreciated and anyone else that might be able to help me.

[Scrapper]

now i'm wandering if it's your catalatic converter??

[xeroinfinity]

Sounds like an injector wire is shorting out.
Double check the wiring harness.
Just my

[odmbc3]

Well after a few snow days and finally a chance to get it tested. The results of the test have shown that the torque converter solenoid is going bad and needs to be replaced. When I reach a speed of 45-50mph or overdrive its losing some contact when it is engaging which is causing the bucking. When you drop it down in 3rd it goes away. There was no codes because there is still contact made by the solenoid. So off to the order the part and hopefully that will solve the problem. I'll keep you posted on what happens and if this really solves the problem or if it is just another elemination that I can add to the list. Thanks for everyones information and input so far on helping to diagnos this problem.

[xeroinfinity]

Most likly the scanner you used doesnt read Trans codes.
Because if it is your TCC then it would trow a DTC.

Here is a link with some good infomation on the TCC.
http://autorepair.about.com/cs/doityourself/l/aa011703b.htm