1989 E30 - Tach not returning to Zero

[KlassE30]

Hello,

I'm having an issue with my E30 325i. When I turn off the car, the tack goes down to zero and about a second afterwards hops up to around 1000rpm mark and rests there when the car is off.

When I go to turn it back on, it will drop back down to zero right before turning over and runs fine. I tried disconnecting the battery, but did nothing.

Why is it resting at the 1000rpm mark when the car is off? Something of concern? how can I fix?

Thanks

[KIRIEIW]

Hello,

I'm having an issue with my E30 325i. When I turn off the car, the tack goes down to zero and about a second afterwards hops up to around 1000rpm mark and rests there when the car is off.

When I go to turn it back on, it will drop back down to zero right before turning over and runs fine. I tried disconnecting the battery, but did nothing.

Why is it resting at the 1000rpm mark when the car is off? Something of concern? how can I fix?

Thanks

The issue is your SI Batterys/ SI Board. After replacing mine the same exact issue your having stopped.

[KlassE30]

The issue is your SI Batterys/ SI Board. After replacing mine the same exact issue your having stopped.

Hey I looked up the SI Batterys / SI Board after reading your post and came across your youtube video. Because i'm not the most mechanical, what do you think a shop would cost to replace this. How long did it take you to take everything out from start to finish.

Thanks for the help!

[KIRIEIW]

Hey I looked up the SI Batterys / SI Board after reading your post and came across your youtube video. Because i'm not the most mechanical, what do you think a shop would cost to replace this. How long did it take you to take everything out from start to finish.



Thanks for the help!

Well to remove it out of the car, all you'll need is a Philips screw driver and some patience. I'm not sure if your car is used everyday? If it's not you can remove the SI board and send it off to one of the members on here who rebuilds them, it cost's somewhere around $120 dollars or so. The other route is to get your whole gauge cluster rebuilt, but if the tach jumping is your only problem, I'd personally just remove the SI board from the cluster and ship it off to one of our members. OR, you can buy the new one and send the old one back after its installed, they charge a core charge.

If you used a shop, I would hope they wouldn't charge you more then an hour of labor to take the old board out, and put a new one in because honestly it wouldn't take me more then 45min to do it. After the old one is removed and the new one is in the car, you can get your core charge back and send your old board out for credit.


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[KlassE30]

Well to remove it out of the car, all you'll need is a Philips screw driver and some patience. I'm not sure if your car is used everyday? If it's not you can remove the SI board and send it off to one of the members on here who rebuilds them, it cost's somewhere around $120 dollars or so. The other route is to get your whole gauge cluster rebuilt, but if the tach jumping is your only problem, I'd personally just remove the SI board from the cluster and ship it off to one of our members. OR, you can buy the new one and send the old one back after its installed, they charge a core charge.

If you used a shop, I would hope they wouldn't charge you more then an hour of labor to take the old board out, and put a new one in because honestly it wouldn't take me more then 45min to do it. After the old one is removed and the new one is in the car, you can get your core charge back and send your old board out for credit.


Sent from my iPhone using Tapatalk

I appreciate the info! I think I may just go for getting a rebuild SI board and attempt the repair myself. I'll get in contact if I have any issues, since it seems you are pretty knowledgable with this.