What the heck is wrong with my tach?

[apexhead]

I just finished an M50 Vanos swap into my 91 318is. This forum has been a huge resource for me and have been able to find many solutions and tips from everyone here. I am having one small problem however. My tachometer is not accurate. It appears to displaying about 25% higher rpms than it is actually turning. I have swapped personality chip in the instrument cluster for one from a late e30 325i ( pn:468 ) and there has been no change. I know that other people have had this problem and the chip is supposed to be the fix but it has not worked for me. I made my own wiring harness by going through the ETMs and everything works except for the abs system and the tach being off. Any help or insight would be greatly appreciatted. Thank you.

[Tchao]

Lol, its it cool? When you can wrap that tach to Eco gauge, then reset back then back again before you hit the rev limter?

You have a 4cylinder decoder thing for the tach.

Remove the trim above the steering column and on the bottom right of the Gauge Cluster you will see a white chip/plug....remove it, and find any 325i e30 and swap it.

I have an extra one if you cant find your own.

[e30nub]

You live in Rohnert Park Too?!

Are you sure you have the right coding plug? I have a 325 coding plug if you need one. Hit me up in a pm and I'll let you come snag it. Plus I NEED to see this swap. I still haven't seen a swapped car.

[apexhead]

I have already put in the coding plug from a 325i and it didnt work. The last three digits of the part number on the plug are 468 correct?

[apexhead]

Figured it out. My main DME ground through the wiring harness was loose and was causing all kinds of problems. Tightened it up and all is well.

e30nub: I work at a shop called GS Tuning in santa rosa and im there every day if you want to see it. A friend of mine just finished putting a s50 with e46 six-speed trans into an 84 325e if you are interested in seeing something a little faster.

[jrdeamicis]

At least you got a free wiring cover.

[apexhead]

Which still isn't installed...