marks_lude

can i test my tach test connector with a voltmeter? and if so how?

or do i have to have a spare tach to do it (in tryin to avoid buying a whole tach just to trouble shoot something)

prelude_h22vtec

well i have seen some mulitmeters have a tach function... i'm not sure it works that way though. i think with those you use the inductive pickup and put it around the wire.

mgags7

what exactly are you troubleshooting?? if you don't mind me asking....

I have never needed to use the test connector....what did you do mess something up with the guages?

marks_lude

well my situation is this.

randomly (on an all stock setup) my tach started to die. it wasnt bouncing up like ive read, it was just cutting out to 0rpm. it got worse and worse and now is at 0prm about 99% of the time.

i figured it was a cracked wire, loose ground, or bad gauges. so then i thought, this is a good time for an EL swap, cuz ill get to replace my gauges and dash harness.

well i did the EL swap and it changed nothing, it acts exactly the same, always at 0rpm, and bounces up to the correct rpm like once or twice a day for a split second.

so now im pretty sure the problem is on the engine side of everything, and i wanted to see if im getting a signal to the test connector, before it heads into the chassis harness's. im not ready to just buy a new dizzy yet.... (btw, the engine runs perfect and has no surging, thats why im thinkin its wiring and not the dizzy)

00preludesh

set multimeter to AC voltage .....ground black lead and probe test connector with red lead w/ car running .....voltage should fluctuate with revving the engine.

mgags7

its certainly not the distributor if it works fine, and if the engine runs ok then the wire to the ecu is working fine as well.

Your problem is behind the dash board, test resistance between the tach pin on the ecu and the tach signal to the guage....

mafia

Befor you buy and do a whoul bunch of stuff PLEASE try this. It might sound silly but i had a simeller problem on 01 caravan. Try a dif battrie and see if that fix's it. When i changed my battrie on 01 caravan for some gay resone it went defect after a while and my the van act VERY weird. So before you waist all kinds of money and time, try what i ask you to try. Hope this help's

marks_lude

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mgags7 &raquo;</TD></TR><TR><TD CLASS="quote">its certainly not the distributor if it works fine, and if the engine runs ok then the wire to the ecu is working fine as well.

Your problem is behind the dash board, test resistance between the tach pin on the ecu and the tach signal to the guage....</TD></TR></TABLE>

well did u see i said i replaced everything dash wise with the el swap? nothing changed after that. its still dead with an intermittent bounce. is there other behind the dash stuff i need to check? (obviously the only harness ive replaced is the upper dash harness. does the blue tach wire run thru the lower harness first? that runs to the stereo, steering column etc?

another important note/question: does the tach wire run to the external coil at all? the reason i ask this is because after my swap i had the typical "no where to mount my coil since the vtec solenoid is in the way" dilemma. i let it sit around ontop of the tranny and the wires twisted around alot, so it could possibly have damaged them.