Help Needed! Misfire at 1600 RPM

[Philthy]

My car misfires at 1600 RPM but runs very good at all other speeds.

I have eliminated the plug wires, coils and chip.

Car has not been run in about a month and did not behave like this when last driven

I feel like it is a sensor.......

Any ideas??????...its driving me crazy....

 

[WS6]

In park revving to 1600? or under load? in first gear or 4th gear?

 

[Philthy]

Its slightly noticeable in Park and very pronounced under load.....

And I have left it in 1st gear past 1600, with the same results....

 

[WS6]

Are your running a scanmaster? or have access to a data stream type scan tool?

Any codes set?

 

[Philthy]

I am not getting any codes.....

No scan master available.....A power logger is in my near future however...

 

[Quiky One]

Check the cam sensor. prolly set a little wrong.

 

[WS6]

If it were me I'd check the free stuff first. Spark plug gap(s), loose plug wire at plug, cam sensor(ala Jason) all sensor connections.

If not those I'd be looking at the MAF sensor as suspect. I'd think you could rule out the TPS based on it happening under all load conditions.

If you have the '89 service supplement manual for the TTA there are some good driveability and emissions troubleshooting flow charts in there.

 

[Philthy]

WS6,

you were on the right track .....it does not do it in park....

It endedup being the lock-up solenoid starting to fail. It eventually got worse then I figured it out......

Bought a new one and will install some time over the next month or so.....

Thanks for the help

 

[WS6]

Interesting....so it it must have been doing it at light throttle in 3rd or 4th gear.