Author Topic: Oil light on and tach not working (Read 4613 times)

xEN6 · « **on:** March 23, 2006, 04:09:19 pm »

Hey all,

So I just got myself a 91 Jetta TD that runs great, almost no rust and that I've known since it was brand new. (My parents bought it from the dealer once upon a time).

Anyhow, it has this one persistent issue that seems to come and go. The oil light turns on and the tach turns off simultaneously. It'll stay that way for a while and then for no apparent reason whatsoever just come back to life. Sometimes in 5 minutes, sometimes in 2 months.

I've searched through the forums here and haven't come up with anything yet... Anyone know what could cause this or where I should begin looking?

bhtooefr · « **Reply #1 on:** March 24, 2006, 03:39:54 pm »

What about the alternator warning light?

Yes, it sounds like it's coming from left field - trust me on this one.

However, tachometer dying is a classic sign of an alternator problem. IIRC, the oil light coming on at the same time as the tach dying is along the same lines.

xEN6 · « **Reply #2 on:** March 25, 2006, 07:44:36 am »

Nope, all the other lights are normal. The only one that comes on is the oil light whent he tach dies.

I went to see a mechanic friend of mine today who also agrees that it's something with the alternator. Thing is, we tested it out and it's working fine. In any case, later this week we're gonna swap it out and see if it makes any difference.

xEN6 · « **Reply #3 on:** April 19, 2006, 09:25:57 am »

Okay, so I've replaced the alternator, waterpump and all the belts with brand new and I am still getting this intermittent tach problem... ARGH!

It seems to come and go as it pleases with absolutely no rhyme or reason. This morning when I was leaving for work it was not working, go about 2 kms down the road and poof, it works. :?:

I really don't wanna tear apart my dash and pull out the console, is there anything else I can check?