Hello, I just replaced my tach in a 76 450 se, the tach shows 2k at idle, when I rev up the engine it goes to 3k then comes back down to 2k. the needle does not bounce around. When I turn on the ignition, the green wire going to the top postshows about 7 volts and the black and red wire has no power. Is that correct.

Does it just go between 2000 and 3000 or does it go above and below, i.e, if you rev the engine is it possible to go above 3000 rpm or does it just stick there? Does it drop below 2000 rpm when you engage the tranny and prepare to move on. I guess what I am saying is that if neither of the above occur, then your tach head is either incorrectly wired or it's fried. Is the seven volt reading with the engine running or with the key on w/o running engine. Need more info.. BTW, what is your idle speed set at??? ;

------------------
Jeff L
1987 300e
1989 300e
1987 BMW 325

[This message has been edited by jeffsr (edited 02-18-2000).]

rpm will drop to 17k, idle set at 830. Tach shows 3500 while crusing at 70mph. Tach will go higher. It just seems to read double what engine is doing at idle. When accelerating tach while jump to 4k and then settle in at 2500, If i rev up the engine, tach will go up after releasing gas pedal. Thanks