Stock Tachometer out

[akirmanidis08]

ive got a 90 laser rst and the stock tach is out

is it called the power transistor that i need to replace? Im confused from reading other posts relating to this.

 

[akirmanidis08]

so apparently i need something called a noise filter. Its some kind of a sensor that filters juice to the tach from what i understand. Any idea what the real name of it is?

 

[Detective Coating]

Yes its called a noise filter, good luck finding a new one from a vendor. Best bet is to get one from someone parting out a car.

 

[BoostedTalonTS]

I believe the part that you are asking about is called a Tach Interface module... They only used these on the 1990 model years, IIRC.

It's a small black box with 3 wires on it... It's mounted to your coil pack's mounting bracket. It's only job is to take reference from both coils and combine them into a single Tach input. -If the car runs fine otherwise, I'd suspect that this module has failed or got unplugged somehow.

Here's a pic:

 

[Detective Coating]

Yes it is 1990 specific.

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[xdxoxuxgx]

I had the same problem in my '90. Instead of going through the wiring and replacing things, I, unfortunately, took the ricer rout at bought an Autometer tach. It's not a 5" monster with a shift light, it's about 3.5" and looks pretty stealthy, I actually kinda like it. I picked it up for like $20 shipped off of an ad on here.

 

[90laserRSfwd]

My tach on my 90 quite working all of a sudden as well, anyone know how to test either (or both) of these parts (noise filter & tach module interface johnson)>?

 

[akirmanidis08]

Well i put in the noise filter, however the tach still doesnt work. Has it ever been heard of for the tacho interface module to stop working?

 

[doesitonall4rs]

its a DSM anything can just stop working on them , i really hope u track down the problem, i had the same problem on my GFs talon and it ended up being her noise filter.

 

[doesitonall4rs]

That is going to be hard to find

nothing is too hard on a DSM!

 

[akirmanidis08]

yea man, im really thinking that its tacho box thats right by the coilpack

and this is true, anything can go wrong on a dsm. Just a few days ago it started messin up with my ignition. I swear i love these cars but they can be such headaches sometimes.

and they are notorious for boost creep

 

[akirmanidis08]

ok so let me get this right.

the tacho interface box and the noise filter are the only things affecting the stock tachometer besides the ecu?

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my next question is where do i get another one besides a junkyard? would autozone have them or do i have to go to a mitsubishi dealer?

 

[scarfacemt92]

I have a 93 talon which just had a wiring swap from a 91 gsx . i got it all back together it starts, lights work and everything, but the tach doesn't work and my signal lights on the cluster just stay on. Any ideas? I tested with both ECUs and still the same problem.

-tom