A wierd post-mod problem
04-22-2008, 09:40 PM
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A wierd post-mod problem Recently had the 98 TA modified/maintained, as follows:
Dart Heads, Lunati cam, fuel pump, timing chain, Weiand intake, Comp lifters,
valve covers, necessary gaskets, dual friction clutch, and had the computer reprogrammed.
I realize that this isn't a detailed list, but I'm trying to be brief and I think my problem arises from the physical installation (or possibly the "cheap" computer work) done by a local mechanic.
Anyway, other than needing a longer warm-up the car runs pretty good, but once it gets warmed up and you really get into it, the problem occurs...
The speedometer and tachometer will beat back and forth and the voltage (via dash and radar detector monitoring) will fluctuate rapidly from 12.2 to 13 volts. The car is runs good about 90% of the time when this happens, but if you really get on it, sometimes the engine will cut out, die and instantly start back up.
Also, cruising at 80, bumps in the road will also cause the speedo and tach to beat back and forth with no performance issues.
It's driving me nuts. Had it back to the mechanic and he thinks it is a loose ground somewhere, says that he has checked everything, and can't find it.
The car with ~97K has various bolt-ons and had no problems before this. Anyone have any ideas. I would greatly appreciate anything.
Ask some questions because this pitiful explanation is not a very good description. Thanks, in advance.
Dart Heads, Lunati cam, fuel pump, timing chain, Weiand intake, Comp lifters,
valve covers, necessary gaskets, dual friction clutch, and had the computer reprogrammed.
I realize that this isn't a detailed list, but I'm trying to be brief and I think my problem arises from the physical installation (or possibly the "cheap" computer work) done by a local mechanic.
Anyway, other than needing a longer warm-up the car runs pretty good, but once it gets warmed up and you really get into it, the problem occurs...
The speedometer and tachometer will beat back and forth and the voltage (via dash and radar detector monitoring) will fluctuate rapidly from 12.2 to 13 volts. The car is runs good about 90% of the time when this happens, but if you really get on it, sometimes the engine will cut out, die and instantly start back up.
Also, cruising at 80, bumps in the road will also cause the speedo and tach to beat back and forth with no performance issues.
It's driving me nuts. Had it back to the mechanic and he thinks it is a loose ground somewhere, says that he has checked everything, and can't find it.
The car with ~97K has various bolt-ons and had no problems before this. Anyone have any ideas. I would greatly appreciate anything.
Ask some questions because this pitiful explanation is not a very good description. Thanks, in advance.
04-23-2008, 08:43 AM
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I was thinking the loose ground also. There is a ground cable (??) on the back of the driver side head that is a bitch to access. This is where I would check first.
