Clutch, Crank Sensor, Master Cylinder Replaced, now Misfiring Randomly…

[Nick Bruns]

So here’s a head-scratcher. 99 Escort ZX2 5MT. 158xxx miles. Just had new clutch, master cylinder, CV axle, and crank sensor done 500 miles ago. Maybe 10 miles after I got it I started getting a blinking CEL which is misfire code. Ran it on my scan tool, and sure enough, misfire on cylinder 2 and 3. It is pretty much completely random. I checked fuel trims myself, and it’s fine. I put in new Motorcraft OEM plugs. The car runs fine with the exception of a slight hesitation when coming out of 1st gear into 2nd from a stop, but that’s mostly cleared up since the clutch was adjusted. It’s completely random. It will blink at a stoplight, when accelerating, normal driving, or decelerating. Car starts fine, runs fine. Idle is a little rough, it always has been. Codes are 98% P0202 and P0203. Occasionally a P0300. I had the tech who did the work look it over and he couldn’t find an issue with it either, fuel trims are fine, spark plugs, plug wires, etc. I’ve been driving it for almost 2 months now and it’s the same issue. I run graphs of LTFT, STFT’s, timing advance too. I took freeze frames whenever I’d get a CEL. My scan tool won’t let me do AFR, but the 02 sensors are working fine.

Now I am thinking I got a bad crank sensor because that is the only thing I can think of that’s wrong with it. Before I take it back a second time, anyone have any input on this?

Thanks!

Topic

[Richard Kirshy]

I would try an OEM crank sensor.
Sometimes after market units have issue playing well.

[Nick Bruns]

Thanks for the suggestion. You’d think they would put OEM parts in it to begin with?

[Richard Kirshy]

More like they charge you for an OEM part but use what ever their part supplier offers.

[Nick Bruns]

Follow up- so I had my car back from the shop a couple weeks ago. Had them go over the crank sensor, which tested fine. No definitive word on the misfiring, other than it isn’t behaving like it’s misfiring. On the scan tool no misfires on the counter

Now a new issue. It’s gotten colder at night in the last couple days (low 40’s) and now the transmission is really hard to shift into 1st, 2nd, and reverse when cold. (5 speed). 1st is the hardest, and it didn’t do this until after all the work was done: new everything behind the flywheel (flywheel that was resurfaced), new trans fluid too. It goes away when it’s warmed up, but for 8 minutes it sucks to drive and I suspect it will only get worse as it gets colder. Before I take the car back for the 4th time, any thoughts?

Thanks

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