PDA

View Full Version : tach issue help!!!!!


maineiac
10-05-2012, 06:36 PM
my tach seems to be working fine on my everyday driving,100 miles a day, went on my weekly 6 hour drive,when i got off hiway,at stop light ,i hate them,tach at low rpm/idle,dropped to zero,when back up to speed fine,slow down back to zero.tach,sender i dont know,is sender in trans,anybody else had this happen?
boatmangc
10-05-2012, 07:45 PM
Since I bought mine, same thing except it won't come back up unless you smack it.

I just bought a new (used) cluster, I'm going to install it this weekend and see if it is better.
capt512
10-05-2012, 10:00 PM
I have the same issue with mine. Randomly smack the dash and it comes back. Am thinking it is the sender? I installed a MM cluster in my 01 CVPI a few years back and never had this issue, the cluster installed had 100k+ miles, so it leads me to think its not a issue with the cluster but instead with the senders going bad.
fastblackmerc
10-06-2012, 03:47 AM
I have the same issue with mine. Randomly smack the dash and it comes back. Am thinking it is the sender? I installed a MM cluster in my 01 CVPI a few years back and never had this issue, the cluster installed had 100k+ miles, so it leads me to think its not a issue with the cluster but instead with the senders going bad.

And where might that sender be?

The tach is connected to the PCM (Powertrain Control Module). If you have to "smack" the dash to get it to work, sounds more like a loose connection. I'd take apart the instrument cluster and make sure the connections are clean and tight.
boatmangc
10-06-2012, 03:49 AM
And where might that sender be?

The tach is connected to the PCM (Powertrain Control Module). If you have to "smack" the dash to get it to work, sounds more like a loose connection. I'd take apart the instrument cluster and make sure the connections are clean and tight.

Mine has been out twice Jim, I understand fully the PCM runs the tach.

I just think some of the tach's were crap.
fastblackmerc
10-06-2012, 03:53 AM
I just think some of the tach's were crap.

Very possible.

Will disassemble my spare cluster to see what the tach looks like.
boatmangc
10-06-2012, 03:54 AM
Pretty much a circuit board.
I will be installing my recently purchased cluster this weekend, hopefully it won't do it.

Stay Tuned
whitey
10-06-2012, 04:15 AM
mine has been doing it for about a year now, I posted and nobody seemed to have an idea on what went wrong, or how to fix it. I took apart my dash, removed the cluster and looked at it, cleaned it up, and still no luck. hopefully a new cluster will fix it.... eagerly waiting for a response.
Spectragod
10-06-2012, 06:43 AM
mine has been doing it for about a year now, I posted and nobody seemed to have an idea on what went wrong, or how to fix it. I took apart my dash, removed the cluster and looked at it, cleaned it up, and still no luck. hopefully a new cluster will fix it.... eagerly waiting for a response.

I have a spare cluster if you need one.
whitey
10-06-2012, 08:52 AM
Spectragod, I appreciate the offer but im currently laid off and I have no money to buy anything. also I have learned to just deal with it, being a automatic car, I don't really need it although it is nice to have
boatmangc
10-07-2012, 04:28 PM
I installed the new cluster today, tach worked great.

Speedo not so much, off by 6MPH and sticks.....
Comin' in Hot
10-07-2012, 05:30 PM
My speedo is off by 5 mph, but reads correctly on my live OBDII data, I would love to fix it
maineiac
10-07-2012, 05:48 PM
mine only seems to act up on long trips,maybee the circuit board heats up after a few hours.
whitey
10-07-2012, 05:55 PM
I installed the new cluster today, tach worked great.

Speedo not so much, off by 6MPH and sticks.....
SOB, i guess you just cant win. well, its good to know where the problem lies. i guess on the bright side, thats i good winning court case if you ever were pulled over, "your honor, the cars speedometer was recalibrated at the shop after i got this ticket, i had no idea i was going that fast...";)
boatmangc
10-08-2012, 03:14 AM
SOB, i guess you just cant win. well, its good to know where the problem lies. i guess on the bright side, thats i good winning court case if you ever were pulled over, "your honor, the cars speedometer was recalibrated at the shop after i got this ticket, i had no idea i was going that fast...";)

Shop? Receipts?
That would probably go as well as my last LEO encounter over window tint..

So next I guess I try and take apart the cluster and see if it is feasible to swap out the tach alone.

It doesn't look like a 5 minute :censor: job.
crouse
10-10-2012, 05:44 PM
Mine does the same thing. Anyone have a sure fix for this?