Fox T-Bird/Cougar Forums

Technical => Electrical Tech => Topic started by: freakaftr8 on July 11, 2008, 11:06:49 PM

Title: Tach jumping around under boost and accel
Post by: freakaftr8 on July 11, 2008, 11:06:49 PM
Hey guys. Well there appears to be a gremlin in my car.. Anyone ever had the tach jump around while under acceleration and boost on a Turbo Coupe? Around 2500 rpm it starts to jump around between 2000 and 4000rpm. I replaced the TFI when I thought it was bad, and still doing it. Not throwing any codes either. Im stumped, if you have any ideas please throw them my way...

Thanks!

Oh yeah, when im at a stop, I notice the speedo bouncing up to 5mph too. Not sure if this is related or not..
Title: Tach jumping around under boost and accel
Post by: vinnietbird on July 12, 2008, 09:31:10 AM
I have a tach if you need one.$15.00 shipped.As far as diagnosing,I wish I could help.Someone will chime in.
Title: Tach jumping around under boost and accel
Post by: freakaftr8 on July 12, 2008, 04:54:48 PM
Can I use any instrument cluster voltage regulator for my tc? Think mine ped out all the sudden... If I bypass it, the guages start working.
Title: Tach jumping around under boost and accel
Post by: freakaftr8 on July 14, 2008, 12:59:55 AM
Think im just going to replace my pip module... It could be bad, whats the big deal about dumping some more $$$ into it, man I already put like 1,000,000 or so into it.. Lol j/k
Title: Tach jumping around under boost and accel
Post by: TurboCoupe50 on July 14, 2008, 01:48:51 PM
About anything in the ign system can cause such a problem(plugs, wires(esp), coil, dist cap).. Last one I I saw that acting similar, I wound up swapping the dist(after changing the TFI)... Apparently the pip had a problem...
Title: Tach jumping around under boost and accel
Post by: freakaftr8 on July 15, 2008, 10:10:58 PM
Well I think I found it, the coil and the #1 plug wire were resting on the back of the alternator stator wire. There is a missing insulation boot on the back of the alternator and the wires were touching. I moved them and seems like all is well now. Thanks for the help guys!