'89 CRX HF + D15Z1 troubleshooting...

[GasSavers_bobski]

Originally Posted by MakDiesel

I also searched similar complaints and will attempt to test my fuel pump and distributor igniter

The ignitor typically manifests itself as RPM-dependant stuttering and missing and/or a bouncing tach, but it wouldn't hurt. How are you going to test the pump? A pressure gauge?

Originally Posted by MakDiesel

P.S. Before I try the brick method, I'll get a short video of the idle in action because diagnosing cars using text is difficult.

Sounds good.
I'll be at my dad's in Mocksville next week if you want another set of eyes and ears.

[Danronian]

It sounds to me like it could be a TPS and/or ignitor issue.

Good luck getting it resolved!

[MakDiesel]

*** UPDATE *** 3/28

Here's what I got through so far:

I used MAF/Sensor cleaner to bog/soak the intake b/c all the carb cleaners I read were not recommended for fuel injected and left a residue, the MAF spray didn't. Still bogged/stalled the engine when sprayed though.

Sprayed carb cleaner on all fittings/hoses, no leaks to be heard. Pinched every hose I could find and the only one to lower the idle was the PCV hose between the valve and the Intake Manifold. Is this normal?

TPS has .5-4.5v range depending on angle, no big spikes in range while operating the plate by hand = OK. Also has 5v supply = OK.

Could not get the EGR off due to a stripped bolt so I tested it w/ vacuum and DMM. The EGR Control Solenoid Valve (in the black box) has 12v supply = OK. There was no vacuum between EGR and black box = OK. When I applied 8mm Hg vacuum to EGR it stalled the engine = OK. When I jumped the connector on the black box to have 12v the vacuum shot up quick = OK. The only discrepancy was the EGR connector only had 2.85v supply when the ignition was on, engine off, instead of the recommended 5v, leading me to believe there is a problem down the line on the yel/wht wire. Rywire instructed me to tap the MAP 5v supply back when I was converting to ODB1 so that's my first avenue for next week. BTW, the MAP has 5v = OK. I swapped in a spare P05 ECU and the EGR still only had 2.85v.

I've included a short video of the warm idle at the end of my precedings, I didn't really change anything so why the rev hang, decel sputter, and accel surge are gone is anyone's guess. I have a feeling it will return until I track down the source. I didn't have time to test the distributor nor did I have a fuel pressure gauge to test that system so I still have a few options. Keep the suggestions coming, I wish I had taped some of the issues before I started. Mak

Video -------> http://youtube.com/watch?v=-63J1nXoLVM

(It idles fine then I jab it a bit, no noted fluctuations...for now. Next time I'll only shoot a video if she acts up and I'll include a sustained rev shot.)

[GasSavers_bobski]

So the check engine light is on, but it doesn't display any codes when you jump the service connector, right? Try unplugging various engine sensors one at a time and see if the CEL will turn off. I seem to recall reading something about the light coming on like that if certain sensors or wires are shorted out. The low voltage on the EGR supply would seem to point in that direction as well.

I'll go check the PCV valve idle thing on my 'Z6, but I don't think it's supposed to make much of a difference idle-wise.

[GasSavers_bobski]

Alright... Pinching off and re-opening the vacuum line between the valve and manifold made about an 80 rpm difference (760 down to 680, or up to 840), but the ECU compensated within a second or two.

[MakDiesel]

Oh, I forgot to mention I have No CEL, except when the VTEC Pressure Sensor connector backs out from time to time (the plastic is cracked). The voltage issue with the EGR apparently isn't enough to through a code. Where in the engine bay is a good 5v source (besides MAP sensor?) Next time I'll re-splice and tap the EGR to see if that clears it up. Mak

[maxxgraphix]

Uh, that sounds exactly like an ECU that's in backup mode. I bet you have a bad ECU or you wired something wrong.

When chipping an ECU and you screw up (like me), the ECU fails to boot and then the engine will sorta run. Like not reving past 4k, poor response, higher idle, slow return to idle. The CE will stay on.

Try another ECU.

[MakDiesel]

I tried another ECU, a P05, and the voltage came out the same. The P07 I'm currently running was bought of a member from here, and he said it was never tampered with. so it should be fine. Also, after probing all of the MAP wires, the yel/wht is half the needed voltage, or 2.5v. The EGR is tapped into this wire, also with 2.5v plugged in, and when both are unplugged, it registers 3.6v for both at their respective connectors. Rywire instructed me to tap this particular MAP wire b/c it supplies 5v. Why is it splitting the voltage? And where else is there a constant 5v in the engine bay? Oh, and still no CEL but I haven't run the car with the sensors unplugged, just w/ ignition power, engine off. Mak

[GasSavers_bobski]

Unplug your ECU, MAP, EGR and TPS sensors. Test the resistance between ground and each pin of the sensor connectors. Test the resistance between the pins at each connector. You should see no connection (off the scale resistance) in each case.

[MakDiesel]

Finally, Finally, found the problem! Seems Rywire instructions had me tap the wrong wire, thus causing the EGR to have fluctuating voltage and a crazy idle and rev decel. It now has 5 volts. What a simple fix it was. Anyway, with that out of the way, an 8 mile test drive ensued and I noticed a few other things:

- Throttle (as in gas pedal/TB plate) still sticks randomly, have to 'jab' the pedal to get it release
- Has a tendency to stutter/jerk/hop at low speeds in low gear
- Has a tendency to do the same at sustained speeds, barely noticeable, usually low RPMs again (below 3k).
- noticeable vibration through the shifter, might have to do w/ harder polyurethane mounts on engine and bushings in shifter being stiffer
- still can't tell if VTEC is engaging, I try to feel for it around 2-2.5k but I second guess myself
- slight gas smell after driving inside car, smell strongest behind driver's seat and next to gas door (only at 1/3 tank if you were wondering)
- NO CEL yay!

So I still have a few issues but my electrical gremlins have been vanquished! Thanks to all who helped out w/ that one....Mak