C3 automatic trans issues

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tdiguardi
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C3 automatic trans issues

Post by tdiguardi » Wed Jun 19, 2019 2:25 pm

I looked at a car that hs 45K original miles on it with a C3 automatic trans. The guy was honest and said it does not shift right, you have to like manualyy shift it. He said the vacume trans module is bad. He could not find an original one??? Are they still out there?
He also said that it occasoinally pushes trans fluid out of some kind of overflow tube? I have no idea?? What does that sound like to you all?
I never had issues with the automatic trans in our 1986 XR4TI when we had it way back??? Tim

Ed Lijewski
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Re: C3 automatic trans issues

Post by Ed Lijewski » Thu Jun 20, 2019 6:54 am

Vacuum control modules are available. Re fluid puking (from the fill tube?) I wouldn't discount the owner having overfilled it. Or the fill tube might not be fully seated at the trans.

YMMV
Descartes: "Cogito Ergo Sum"
Lijewski: "Sum Ergo Drive-O. Mucho!

tdiguardi
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Re: C3 automatic trans issues

Post by tdiguardi » Thu Jun 20, 2019 11:20 am

Dumb question but does an original (made for Merkur) automatic trans module work any better than a generatic aftermarket one? Tim

Ed Lijewski
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Re: C3 automatic trans issues

Post by Ed Lijewski » Thu Jun 20, 2019 1:02 pm

Many aftermarket parts are improved over original OEM installed units (TFIs, e.g., to strengthen weaknesses/failure points). The vacuum control module likely isn't one of such items given it's mechanical simplicity (internal spring, internal diaphragm, metal case).

YMMV
Descartes: "Cogito Ergo Sum"
Lijewski: "Sum Ergo Drive-O. Mucho!

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