Having some issues with the tachometer in the cluster I just put in my DX.

Needle would sit at 0RPM and after a few minutes, shoot up to 6000 RPMs and stick there, before eventually dropping back down to 0...It would occasionally work correctly but I think it was slow to react to changes in speed.

Last night I am driving home, and needle shoots up to 6000, sits there, and then all of a sudden shoots past 9000 in to the black, almost coming completely back around to the 0 point. Now it stays in the black, and will drop down to 6000 before shooting back past 9000.

What's the deal? Anything I can check on my end before calling this cluster broken.

Thanks.

- jefe

 

bump

 

i had that happen , 1 week later my car wpuld not start.
It turn out to be a loose groung wire at the termostat housing.

 

Also look at the dizzy/ignitor. When it's on it's way out, it tends to wig out the tach.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dpaton &raquo;</TD></TR><TR><TD CLASS="quote">Also look at the dizzy/ignitor. When it's on it's way out, it tends to wig out the tach.</TD></TR></TABLE>

Would that cause any other issues....mis firing or something more obvious. Car is running great other than the tach.

 

i was also going to point you to the ignitor.
it could cause the problem your having.
Check your grounds first. That does not take long to do.
Don't just do a visual wiggle the wires around.
On my car the ground wire appeared to be tight but it was not.

 

Check your grounds. My car was doing that, plus cutting out, and all I did was tighten all the ground wires. If not grounds, probably dizzy.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by jefe &raquo;</TD></TR><TR><TD CLASS="quote">Would that cause any other issues....mis firing or something more obvious. Car is running great other than the tach.</TD></TR></TABLE>
Only at the very end of the ignitor's life. At the beginning, it just gets noisy and messes with the tach. The ECU seems adept enough at noise cancellation on the dizzy feedback line that it knows what's good and bad data. That and the cluster is particularly succeptable to noise on the tach line. It's not filtered worth crap.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dpaton &raquo;</TD></TR><TR><TD CLASS="quote">Only at the very end of the ignitor's life. At the beginning, it just gets noisy and messes with the tach. The ECU seems adept enough at noise cancellation on the dizzy feedback line that it knows what's good and bad data. That and the cluster is particularly succeptable to noise on the tach line. It's not filtered worth crap.</TD></TR></TABLE>

What kind of noise are we talking about? I have a crazy mysterious noise that teases me from time to time...comes out of hiding for a few minutes then goes away....and I havent been able to pin point where its coming from.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by jefe &raquo;</TD></TR><TR><TD CLASS="quote">

Would that cause any other issues....mis firing or something more obvious. Car is running great other than the tach.</TD></TR></TABLE>


nope, i had the ignitor go out on my car and the tach just went crazy for a week or two, then one day it wouldnt start.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by pat92si &raquo;</TD></TR><TR><TD CLASS="quote">nope, i had the ignitor go out on my car and the tach just went crazy for a week or two, then one day it wouldnt start.</TD></TR></TABLE>

The ignitor is inside the distributor, correct? That small square box thing?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by jefe &raquo;</TD></TR><TR><TD CLASS="quote">What kind of noise are we talking about?</TD></TR></TABLE>
That'd be electrical noise...not the kind of thing you'd hear. If you have a bearing going in your dizzy, it'll make an intermittant squeak of squeal, but an ignitor doesn't fail in an audible way, unless you count the silence that eventually comes when your car won't start.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dpaton &raquo;</TD></TR><TR><TD CLASS="quote"> unless you count the silence that eventually comes when your car won't start.</TD></TR></TABLE>

heh.

 

Still looking into it, but found some stuff with the distributor. Somehow, I only had one bolt out of 3 holding the distributor cap on...so it was loose which I could imagine could cause some contact issues.

I took the cap off and was taking the dist. rotor off, noticed a small crack in it...and as I was taking it off, the rotor just snapped in half with little effort on my part....I suppose another potentail problem causer.

Anyways...going to get this stuff fixed up...will post again to say whether or not these help my tach issue. All wires with the ignition coil looked tight.

 

Posting an update to close out the thread so it has a final solution to it.

Got the new distributor parts, installed them and re-set the ECU for good measure. Tachometer was still acting up....not doing much....sitting in the black past 9000 RPM's and not moving at all.

So then I took apart the cluster and reset the needle back to 0...made sure it was moving smoothly and not getting hung up anywhere....once I put the tach back together, it started working....so far, it seems just fine now....not getting stuck, changing quickly to revs, etc.

Anyways...just thought I would post.