Intermittent Electrical Problems on a ’93 MKIV

[Guest gjs_cds]

Hi Everyone,

 

I’ve got a ’93 MKIV, normally aspirated, automatic transmission. (Ok, Ok, I know—stop laughing.) But to the point, I’ve got an intermittent electrical problem; one that I’ve had for about 4 years. NOBODY has been able to figure it out. So I’m to the point where I’m wondering if there are people out there that can just replace the whole darn electrical system. I’ll drive relatively long distances to find a competent repair facility that can do such a task.

 

I live in the mid-south region of the United States (Mississippi). If anyone has any ideas or suggestions, by all means—please let me know. I’m at my wit’s end…

[TrickTT]

Its a bit of a long way to come, but there's a few electrical geniuses on here,a description of the problem might help. I would think replacing the whole lot would be hugely expensive.

[JustGav]

A full loom is a LOT of work, seriously, because the dash board needs to come out in order to do it...

 

This being a UK board you might find it a little tricky... altho I'm sure there will be no shortage of offers if you are willing to fly someone out *grin*....

 

What are the electrical faults?

[Guest gjs_cds]

Hi Guys,

 

I knew this was a UK board, but thought that there may be some readers from across the pond…

 

My issues pretty odd, and seemingly non-related. (Although I’m pretty confident that there’s got to be a central cause somewhere…)

 

The fuse-panel down by the brake/clutch panel… Fuses often get burned out. Not full-on blown, but burned such that they work intermittently. Replacing the fuses helps the symptoms, but not the problem. They will “burn-out” again. (The fuses don’t show blown when tested…but when you take them out, the fuse-leads are black and charred, and thus can’t pass current.)

 

The over-drive (Auto Trannie) automatically toggles on/off, about once per-second. (Unless I just turn the OD off.) The cruise-control lights up, but does not work. (Sometimes, the CC light flickers on and off.) Often times, things like the turn-signal will draw current away from the stereo, causing the stereo lights to dim when the turn-signal light is activated.

 

And what’s really getting to me is (I think) the electronic Auto-Trannie shifter. I’m intermittently losing power upon acceleration—almost like the car’s trying to start in 3rd or 4th gear. It sputters and stutters for a while, unable to figure out which gear it wants to use. In a sense—it almost feels like its running out of gas or a fuel-pump issue…but with all these other electrical issues, I’m betting on some central computer auto-transmission issue.

 

These are just a few of my electrical problems. If any brilliant minds out there can come up with a theory on a *solution*… I’m all ears. I’ve taken this car to shop after shop for the past 4 years, and no one’s able to figure it out.

 

All my best from across the pond,

 

Greg

[TrickTT]

In my experience intermittant faults like yours are caused by a dodgy earth point somwhere on the car causing a power feedback through various other electrical items. I would guess at somewhere behind the dash or on the transmission tunnel. Best bet would be to remove most of the dash and work your way through the earth points one at a time. Unbolt the connector, clean it and mark it with paint so you know its been done.

[Guest gjs_cds]

Thanks Trick152... I just read (this morning) a similar article from a motorcycle magazine saying the same thing.

 

I'll give it a go this weekend and see what happens!