Hopefully someone can help..
My son has a 1991 Coupe 3.1L with Headers, problem started about 3 days ago... Problem is car runs smooth, but on occasion sputters, is sluggish. Best way to describe the problem is its running on 6 cylinders, but throught the RPM range it runs like you flipped a switch and cut electrical power to one or 2 cylinders. Then goes back to 6, back to cutting out. Almost like having a straight line for 1 foot then a spike up.. then back to normal. When you try to floor it, it has no power at all when its in the "sputtering mode" almost like trying to jam a radar signal.. Best way to describe it is there is moisture under the distributor cap and there is an intermittent cut out..

So last night, We checked the wires and found 1 terminal on the cap was coroded with white chalk type material when you pulled the wire, and the wire had corosion so we changed it.. The wire and cap. Drove it again.. ran smooth, but then about a mile into the drive, same problem.. brought it back, pulled plugs, they looked good, but we changed them.. drove it.. same problem,, came back.. changed ignition module.. drove it.. same problem...

Car is full with premium fuel 93 ocatane... When I plug my snap on scanner into the port.. no codes at all, car in closed loop.. o2 sensor working correctly. Fuel pump is about 6 months old... Tried Idle relearn.. nothing seems to work..... Also injectors are about a year old, these are replacements and purchased from Fuel Injection connection in georgia.

Any ideas are appreciated.. HELP!

 

Could be just about anything. Guess I'll throw a few ideas out there and see if any of it might be a possibility.

1.Vacuum leak
2.Leaking egr valve or plugged pcv valve
3.fuel pump not working properly or clogged fuel filter
4.Leaking head gasket.
5.Check the spark gap.
6.Timing
7.check the compression.
8.??

 

1) Vacuum leak checked - none present
2) Car has no EGR, its been removed. It ran fine ever since it was removed over a year ago, car also has no cat either
3) Changed Fuel Filter last night
4) Leaking as in how?
5) Spark gap is good. .045
6) Timing reset to 10 degrees befor TDC as per shop manual
7) Havent checked compression yet.

Last night changed Fuel Filter, Cleaned out IAC and replaced TPS. Car will run and but has absolutely no power at all.......