93rustanglx

Hi, I'm new to the Forum but I love the Mustang!

I've got a 93 mustang 2.3 liter automatic and the rpm gauge either doesn't work, reports only half the rpm or works perfectly. When the tachometer stops or malfunctions, the check engine light comes on (CEL). If anybody has a suggestion please let me know. The car runs fine independent of the tachometer check engine light problem.

Steve
Ontario

P Zero

It sounds liek you have a loose or bad connection. Im not positive how the tach is hooked up on yours, but I'd imagine that check the lead that goes to the coil. It should be marked tach. If its hooked up and doesnt appear to be loose, you might have to remove the wire and clean the connection. I imagine that they use a lot of salt where you live, so that will cause corrosion build up. But if thats not the case, you might have a broken wire inside of the sheathing. Without looking at the car that all I can think of.
-P.

OnyxCobra

I had a tach problem for a while, it either worked fine (rare) or would just read really low or not move at all. I took the gaugepack out at least 3 different times looking for stuff and never found anything, turns out the problem was the gauge pack was never pushed together hard enough, so one time i just put a lil extra muscle into it and it snapped together a lil more and it's worked ever since...

93rustanglx

Well, still no luck. Sometimes it works, sometimes it half works, sometimes it doesn't. I wonder if it has to do with the 2 coil packs for the 8plug 4cyl ignition. Took the dash apart, gauges seem tight. Cleaned the wires that plug into the coil packs. Changed the fuse. Has anyone ever had the tach itself go bad? The car is a 1993 with 193,000km. Thanks for the great info so far!

Steve
Ontario

xzo6

It may be a sign that your computer is having issues.If it's the original it's starting to get up there in age.

93rustanglx

When your ICM starts to go bad your tach will read half rpms, then eventually stop reading them all together, then it will stop running your primary plugs, which means your car is done for.

Thanks to Shinlee for the post in RPM Gauge. Thanks everyone for the support, this forum is the best!!!

Steve
Ontario

93 Mustang LX 2.3 auto