First off, let me start by saying thanks. I've been checking out this site for years, but finally became a member yesterday. Thanks to the SEARCH feature and EVERYBODY'S replies, you guys have bailed me out of plenty messed up situations. So thanks again!!!

Since i'm the new guy around here, here's the layout...

2000 EM1
'98 ITR swap
S2S1 Cams
4-1 DC header (dented to all hell)
RC 440 Injectors (I know their a little big, but I got em for free)
Tuned with Hondata

196hp
131tq
On A Dynojet (I'll Post A Graph When Possible)

Alright, on to the problem....

My tach bounces between 2000 and 4000rpm all the time. As soon as I hit 2000 it starts to bounce until I clear 4000rpms. I also have an Autometer Tach hooked up, but that works fine.

The battery is good.
Cap and Rotor are new
Ignitor is new
Thermostat ground is fine

Any other ideas before I have to start messing with wires behind the dash?

 

Usually the IACV (Idle Air Control Valve) is messed up, or has a leak or something. Or theres another vacuum leak somewhere.

 

i would say ignitor or vss, you said u got a new ignitor tho... does the spark breakup in the higher rpms (6k+)?

 

Spark seems OK, IACV is only about 3 months old. I haven't checked all vac lines yet.

 

so the tach just bounces but the car acts like its still fine right.. i mean, it doesnt bog, shudder, etc?

Maybe your alternator is dying? Try having Advance Auto or a similar place do a checkup on your electrical system...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by turbotime &raquo;</TD></TR><TR><TD CLASS="quote">so the tach just bounces but the car acts like its still fine right.. i mean, it doesnt bog, shudder, etc?

Maybe your alternator is dying? Try having Advance Auto or a similar place do a checkup on your electrical system...</TD></TR></TABLE>

If the car runs fine maybe it's just a bunk tach as well.

 

i had the same problem with a bouncing tach except mine was the apxe-i tach, cause my car didn't have a tach...so i thought it was the tach and bought a new one but it did the same thing. so i went to a junk yard and bought a cluster out of the ex civic and no more tach problems.

 

does it jump when idleing or just when moving betweem 2k-4k? check the FITV if its when idleing

 

since the Autometer Tach works fine the ignition system is obviusly not the problem.

it could be the tach itself going bad. It could also be the screws that hold the tack into the cluster that are a little loose. It's been a problem on a few clusters on here lately.

 

ya we kind of need to know if the car runs fine, and if its just the tack bouncing around because that is interesting that your other tach works fine. it would just make me believe that there is something wrong with the stock tach.

 

Sorry guys for not getting back on this yesterday. Being the new guy on here kinda sucks, 5 posts go by so quick! Alright, back to business.....

The car runs great, no bogging or hesitation.
As far as I know, the Type-R doesn't have an FITV.
All screws in and around the cluster are tight.
Last night we put in a different cluster and it did the same thing.
I'm starting to think it just might be a messed up wire somewhere

I totally appreciate the replies, and any help.