Contour Enthusiasts Group Archives Forums General Troubleshooting I'm Stumped.....

Problem: Upper RPM stumble / let up in power - intermittent. Feels like a momonetary (or not so monmetary) lift of throttle. More common when car is at full operating temp, sometimes felt at mid throttle stomp but mostly in 3rd or 4th above 4k.

I thought maybe clutch slip but I only have 10k on the grizzly street (kevlar puck) setup. OBD-II captures of MAF, O2 and RPM vs speed haven't shown anything conclusive (to me) yet.

OBD Data:
Long term fuel trim on bank 1 is like 18% at idle, but as rpm increase trim drops and goes negative by a few percent above 4-5 k.

FT bank 2 is about 12 and remains constant through rpm's.

Just recently picked up a few type B misfires (no DTC's yet) from cylinder 3.

Manifold vacuum is a rock steady 21".

Fuel pressure is like 34, just a bit under the lower limit of 35.

Cylinder 3 plug and wire look more or less brand new ('cause they more or less are).


Soooo - anyone have any suggestions? Maybe cylinder 3 injector crapping out on me?

I have no cats to plug, a new MAF, fuel filter and relatively new plugs and wires.

Would appreciate thought or suggestions from the experts or non-experts with an opinion

Thanks alot -

Secondary Flutter
I had this problem! Pin them open and see if the problem goes away...

(possible fixes)
Disconnect the IMRC plug (clean if necessary) and pack it full of dielectric grease and re-install it.

Hand operate the secondaries to full travel several times. They could be having travel problems due to crap build-up inside them (See FAQ on cleaning)

IMRC Replacement. (okay that's obvious eh?)

Bad plugs and/or wires
How new is new?
~Check them - that was simple...

Thanks

I read one of your earlier posts and thought, "self, it's got to be IMRC" - I tied them up for a week and still got the flutter/let up

Wires are about 11 months old, plugs about 2,000 miles from when I cleaned my upper (thought maybe a vacuum leak from screwing with the upper and injectors - I had to go back in before to replace the injector to manifold seals to fix a leak from the first time). I re-checked the #3 wire and plug today and no signs of arcs - maybe a coil pack???

It's slowly getting worse - so at some point I expect I'll have a hard failure that should be easier to diagnose.....