I hope so - hoping is starts! Should know tomorrow. Main concern is if the ECU works.
ZC DOHC 1991 Hatchback Transplant - Epilog
- Thread starter Dual-500
- Start date
- Replies 173
- Views 39K
We may earn a small commission from affiliate links and paid advertisements. Terms
Thanks - yeah, I like the colour combination also. The tail lights were in it when I bought the car - it also had a matching reflector between the tail lights - but, the red original rear reflector was with the car in the back, so I put it on and threw the shiney (Ricer) one in the recycle bin.
I priced stock tail lights a while back when at a local junk yard picking up a second valve cover to paint for the D16A6. The guy only had one and wanted $60 for it so I declined. They will most certainly be changed out.
Last edited:
Ok, the Hog's all wired and put together - vacum lines, vapor lines, coolant lines, fuel line, exhaust, ECU, adapter harness, OBD1 O2 sensor, tranny linkage, starter wiring, sensors - everything connected.
Installed charged battery and cranked it over with spark plugs out to build oil pressure - waited for OP idiot light to go out. Installed distributor and tried to crank her up. NADA. Pulled #1 plug wire and no spark.
So, looked at some schematics and will begin troubleshooting tomorrow night. Going to make a pass across the front and back yard with lawnmower tonight. Have rent car until Tuesday 7/5. First think I"m going to try is swap the white wires on the 8 pin connector the distributor connects to. If that doesn't get it done, then ring out the harness between distributor and ECU pin to pin. Will also confirm power running to distributor. I'm thinking this shouldn't take to long to resolve.
When I discovered the ignition issue, since there are many variables in the equation, I ordered some backup/test parts. P28 ECU, used MAP sensor, new TD-43U distributor. The goodies should arrive this week.
Also ordered up a chip for the P06 ECU from winfab_tuning that's supposed to be specifically for the DOHC ZC motor. This will be for break-in as I'm going to have one of the ECU's setup with Hondata S300 once it's broken in. I'll install the ship in the P06 once troubleshooting is done and this thing is cranked up and drivable.
More to follow.......
Just got this from favorite uncle on email - gotta post this one as it's a scream: "Redneck Duck Paintball"
http://www.senorpanadero.net/uploader/userfiles/stevew/Redneck%20Paintball%20Duck.wmv
Installed charged battery and cranked it over with spark plugs out to build oil pressure - waited for OP idiot light to go out. Installed distributor and tried to crank her up. NADA. Pulled #1 plug wire and no spark.
So, looked at some schematics and will begin troubleshooting tomorrow night. Going to make a pass across the front and back yard with lawnmower tonight. Have rent car until Tuesday 7/5. First think I"m going to try is swap the white wires on the 8 pin connector the distributor connects to. If that doesn't get it done, then ring out the harness between distributor and ECU pin to pin. Will also confirm power running to distributor. I'm thinking this shouldn't take to long to resolve.
When I discovered the ignition issue, since there are many variables in the equation, I ordered some backup/test parts. P28 ECU, used MAP sensor, new TD-43U distributor. The goodies should arrive this week.
Also ordered up a chip for the P06 ECU from winfab_tuning that's supposed to be specifically for the DOHC ZC motor. This will be for break-in as I'm going to have one of the ECU's setup with Hondata S300 once it's broken in. I'll install the ship in the P06 once troubleshooting is done and this thing is cranked up and drivable.
More to follow.......
Just got this from favorite uncle on email - gotta post this one as it's a scream: "Redneck Duck Paintball"
http://www.senorpanadero.net/uploader/userfiles/stevew/Redneck%20Paintball%20Duck.wmv
Last edited:
GlassHeadlights
West West Yall
Dist plugged in? I've done that a few times with fresh swaps. Did you have to cut/replace the distributor wiring for OBD1 plugs? Check wiring if so. The white wires are just different grounds in the dizzy for different sensors so it should throw a code (like mine did when reversed).
Last edited:
Yeah, it was hooked up. According to the schematics the whites are for CYP sensor which could be a ground/signal, or if it's common mode rejection type circuit (balanced) it would have also been signal. The other white is the trigger signal (unbalanced) to the ignitor or the one that signals from the ECU to the distributor to fire the coil for spark. Not sure if it carries a logic low or logic high to trigger. Injectors carry a logic high to fire so I would guess it gets a positive logic pulse as well. But, who knows? Maybe I'll put a scope on it sometime.
I may end up with a scope on it this week if I can't get it running with a white wire swap and the parts swaps I ordered - dizzy and P28 ECU.
Here's the OBD1 schematic I am using. White to white (pin 8) and the other white from the car harness goes to the YEL/GRN (pin 2) which as you can see are one leg of the CYP sensor and the Ignitor Triger or IGN (Ignition) functions.
Backup distributor and ECU arrived this week. I installed the P28 ECU and new TD-43U distributor and cranked it over - no spark.Having eliminated the distributor and ECU as potential culprits, it's time to tear into wiring, fuses, etc. Will begin this evening.I'll check the Black/Yellow for power +12v and then chase the white wires from connector to the ECU. Hopefully, this doesn't get to involved.That being said, I have the tools (VOM, DVM, Tektronics Scope, Signal Generator, SledgeHammer) and the time to do it this 3-Day 4th of July weekend. Finding schematics isn't too difficult online. I also have a Chilton and a Hayes service manual for the car.The problem is finding technical data that coincides with other technical data. Or, finding complete technical data. Wire by wire, matching by colour modification instructions are great when things work, but of linited value when troubleshooting is necessary. In this case there are 2 white wires on the car harness side - one goes to the white wire on the OBD1 plug for distributor and the other goes to the yellow/green or green/yellow on the distributor plug. That's where I will start - ring out the wires and then swap if necessary.I didn't even want to start swapping wires without some backup test parts - so I ordered up a spare ECU and distributor. Now I know with a degree of confidence where to focus my effort.
GlassHeadlights
West West Yall
You got er under control lol. Damn electricians and their understandings... :<
Well now, there may lie a problem - I won't know till I get started if my head is outta my ass today or not - could go either way.......
Gonna suit up (overalls and work boots) and head out there in a few minutes. Pulled some good schematics today - hopefully they are representative of the wiring in my chassis.
Last edited:
Thanks for the vote of confidence. Time for a Havana - I"m more a cigar afficianado myself. Smoking up on a Montecristo #2 in about 10 minutes.
Troubleshooting has been interesting. Here's what I found thus far, I'll post some more "How I"m doing it pictures" soon as it may help some of the newer guys. Have a few nice tricks that may make it easier.
I rang it out with a DVM set to "Continuity Check or Diode Test" so it makes a beep tone when the leads are touched together or the circuit being tested has continuity.
Thus far, the wiring looks right and appears to have good solid connections. I rang it from the 8 pin connector at the distributor all the way to the ECU and checked both the OBD0 connectors and also hooked up the OBD0 to OBD1 adapter harness and confirmed the OBD1 signals were on the correct ECU pins. Everything checked out ok. I didn't check the blue tachometer strobe line but did check the Black/Yellow at the distributor for 12v when the ignition switch is turned on. Everything looks to be Ship Shape.
What I did notice when I started to ring out the harness is there are colour differences between 2 pins on the JDM OBD1 8-pin distributor harness connector that came with the engine, and the connector on the TD-43U distributor. The Orange and White wires that carry the CYPP & CYPG signals (appear to be Crank Angle Sensor) are flopped from one another.
I noticed this when I started the continuity ring out, but went ahead and checked the wiring all the way to the ECU and I also checked each wire for a short to ground and for wire to wire short. All checks out good.
Here's a couple of pictures:
On the left side is the distributor connector - notice the white wire at the top and on the car harness side (connector that was on the ZC engine harness that I spliced into the car wiring harness) is orange.
With the connector flipped over, the distributor connector on the left has a orange wire at the bottom and the JDM connector on the right has a white wire.
The signals are for Crank Angle per the data I have. I can swap them around so they match and will do so tomorrow - almost midnight here now and I'm not going to fire that thing up this late out of respect for my neighbors - or, at this point I should say attempt to start it because that may not be the problem.
With the wires reversed, the signal from the magnetic crank angle sensor will be reversed in polarity and not correctly trigger the Zero Crossing Detector in the ECU. Without that signal, no spark as the Distributor doesn't sense any rotation.
Seems strange to me how that situation could exist. Not even sure it that's the problem - but, I suspect it is. More to follow tomorrow.
EDIT: Tomorrow when I continue troubleshooting first thing to do will be to wire up a miniture toggle switch to the ECU CEL loop. Also, going to put a miniture toggle swith on the timing loop so timing can be set by flipping a switch as can CEL code dump. Then install the distributor and crank it over with no spark plugs and the fuel pump disconnected. Then, fiip the CEL switch and look for ECU error codes. I expect to see a Crank Position or some such code. Hopefully that will be the case, then swap the orange and white wires at the distributor, install distributor, put the spark plugs in it, connect fuel pump connector and give it a try for first startup.
Last edited:
Wired in the switched for timing and CEL. Re-installed distributor. Cranked it over, no spark as expected. Flipped CEL switch no codes - nothing. So, swapped the peach and white wires at the distributor. Cranked it over, no spark, no codes. That was with the P28 ECU in it, think I'll have a go at it with the P06.
WTF OVER!
Inside cooling off for a while and looking over schematics again. Gonna have a good look through this supposed HELMS version I downloaded last night.
http://www.senorpanadero.net/uploader/userfiles/stevew/Honda%20SiR/Honda%20Civic%201991%20HELMS%20Wiring%20ED3%20ED4%20ED6%20ED7%20USDM.pdf
Check voltage to ECU, fuses, relays, etc.
WTF OVER!
Inside cooling off for a while and looking over schematics again. Gonna have a good look through this supposed HELMS version I downloaded last night.
http://www.senorpanadero.net/uploader/userfiles/stevew/Honda%20SiR/Honda%20Civic%201991%20HELMS%20Wiring%20ED3%20ED4%20ED6%20ED7%20USDM.pdf
Check voltage to ECU, fuses, relays, etc.
Last edited:
Working my way through the maze. No CEL codes. Also, no CEL when ignition is turned ot with engine off.
Ahh, seems the yellow CEL used to come on when the engine was off, like prior to startup, then extinguish.
Checked ECU fuse and it's ok. ECU is sitting on carpet on the passenger side. Maybe it needs a mechanical ground to the chassis to function.
Will explore that after a lunch run.......
Can someone confirm the CEL - does it normally come on when igniton switch is turned on without hitting the starter?
Ahh, seems the yellow CEL used to come on when the engine was off, like prior to startup, then extinguish.
Checked ECU fuse and it's ok. ECU is sitting on carpet on the passenger side. Maybe it needs a mechanical ground to the chassis to function.
Will explore that after a lunch run.......
Can someone confirm the CEL - does it normally come on when igniton switch is turned on without hitting the starter?
The ECU was the issue. Ground at the thermostat on engine was loose. CEL comes on now when key is turned on.
Started it up and let it idle for about 30 seconds, and shut off. Dumped codes from ECU - 21 & 41.
21 is VTEC spool solenoid valve - Thinking this won't be an issue?
41 Primary Oxygen Sensor Heater - will work this one tomorrow.
Started it up and let it idle for about 30 seconds, and shut off. Dumped codes from ECU - 21 & 41.
21 is VTEC spool solenoid valve - Thinking this won't be an issue?
41 Primary Oxygen Sensor Heater - will work this one tomorrow.
Put the P06 ECU in it to clear the VTEC CEL error code 21 that the P28 generated.
Started it up - the idle is surging and it's throwing CEL code 14 and 41. 14 is the for the IAC/EACV - I used the connector off the D16A6 FITV for the EACV and possibly need to switch it over to what was the D16A6 IAC. Going to delve into schematic and figure that one out.
For the CEL code 41 I'll check out the wiring in the O2 sensor circuit. Toggle switches sure are nice on the ECU for Timing and CEL dump functions instead of fumbling around with paper clips. Probably just my personal opinion,- but it's much easier. Shut engine off, flip toggle and turn on ignition switch and it dumps codes.
Completed initial engine run a few minutes ago - let it idle for about 20 minutes, watching temperature and oil pressure closely - topped off coolant, checked for leaks, radiator cooling fan operation fan, etc. Also, checked battery voltage, just over 14 volts and the engine tone changed from load condition changing when I turned the headlights on. Translation: the new 160a alternator is working as it should.
Cooling down now with large fan on it - should be ready for head re-torque in 2-3 hours. Probably won't run valves (rocker arm clearance) again until first oil change. I have a nice 14mm socket that has the u-joint built into it - short enough to fit the DOHC ZC head bolts and keep the extension straight enough to torque head bolts without removing cams.
Once it cools down a bit, I'll tackle the wiring for the EACV & O2 sensor.
Motor sounds good when giving the throttle a whack or two. Sounds quite a little bit healthier than the wore out ole D16A6. PIcks up RPM much faster.
Started it up - the idle is surging and it's throwing CEL code 14 and 41. 14 is the for the IAC/EACV - I used the connector off the D16A6 FITV for the EACV and possibly need to switch it over to what was the D16A6 IAC. Going to delve into schematic and figure that one out.
For the CEL code 41 I'll check out the wiring in the O2 sensor circuit. Toggle switches sure are nice on the ECU for Timing and CEL dump functions instead of fumbling around with paper clips. Probably just my personal opinion,- but it's much easier. Shut engine off, flip toggle and turn on ignition switch and it dumps codes.
Completed initial engine run a few minutes ago - let it idle for about 20 minutes, watching temperature and oil pressure closely - topped off coolant, checked for leaks, radiator cooling fan operation fan, etc. Also, checked battery voltage, just over 14 volts and the engine tone changed from load condition changing when I turned the headlights on. Translation: the new 160a alternator is working as it should.
Cooling down now with large fan on it - should be ready for head re-torque in 2-3 hours. Probably won't run valves (rocker arm clearance) again until first oil change. I have a nice 14mm socket that has the u-joint built into it - short enough to fit the DOHC ZC head bolts and keep the extension straight enough to torque head bolts without removing cams.
Once it cools down a bit, I'll tackle the wiring for the EACV & O2 sensor.
Motor sounds good when giving the throttle a whack or two. Sounds quite a little bit healthier than the wore out ole D16A6. PIcks up RPM much faster.
GlassHeadlights
West West Yall
Unplug the IACV when it starts to surge. The idle should drop right to 700-800. Also take off the intake pipe and there should a finger sized hole for the IACV circuit. Plug it with your finger and idle should also drop right down.
Then troubleshoot IACV problems from there.
Then troubleshoot IACV problems from there.
Did just that (pulled control harness) and it settled it down - can also get it there opening butterfly a little to bring RPM up and then slowly closing it to idle. I"ll try interrupting the air intake today.
Also going to try the P28 ECU again - first runs with that one didn't have any idle issue. Suspecting the ECU - almost acting like a dried out capacitor isn't dampening the circuit reaction - couple that with the lightened flywheel and higher compression which makes the engine a bit more responsive.
Going to continue tracing wiring on the O2 sensor heater circuit code 41 first this morning, then return to the idle fiasco.
For the idle, I was thiniing the EACV/IACV may be sticking. Will clean again and maybe douche it out with some WD-40 to lube it a little. May take it to the electronics bensh and stimulate it with 12v and see what it does. Have the valve off the D16A6 for comparison. Too bad it won't fit the ZC intake manifold port.
I've been searching around for ECU theory - that would be nice to have. Not basic "how it works theory" on the ECU with regard to engine operation - not to difficult to understand or find the discussions on that. What I"m looking for is the fault code theory - what conditions trigger faults? Not just "The IACV/EACV is "Bad", but what conditions must occur before it "Faults Out"? i.e. current draw from the valve? Too high or too low? Or engine RPM fluctuations, or lack of RPM change when valve is signaled to open? Etc. That information would make it a hell of lot easier to troubleshoot.
Last edited:
Went out and setup cooling fan and rolled tool cart to the car. Took a quick look at the IACV/EACV and tested it on the car as the coolant lines are connected and the cooling system is charged.
Tested the old one from the D16A6 first using alligator clip test leads from the battery terminals. It clicks and you can see the accordian type plunger seal contract when voltage is applied. Then removed the one from the ZC and did same check. It works fine and plunger moves freely open and closed - snaps open and shut with authority. Checked it for polarity - works either way which means the solenoid core is non-magnetic and it woudn't be susceptible to reversing the wiring polairity between the pins.
I have a strobe from the model airplane toy chest. Will need to put a couple of marks on the harmonic balancer for that to work. The static idle may be set too high as the idle is over 1000 RPM with the IACV/EACV control wire disconnected - Helms calls out 420 to 450 RPM with the valve disconnected.
Downloaded the Helms book and printed the engine wiring schematics for the 1992 Honda with 4-wire O2 sensor to track down the CEL fault code 41.
More to follow.......
Tested the old one from the D16A6 first using alligator clip test leads from the battery terminals. It clicks and you can see the accordian type plunger seal contract when voltage is applied. Then removed the one from the ZC and did same check. It works fine and plunger moves freely open and closed - snaps open and shut with authority. Checked it for polarity - works either way which means the solenoid core is non-magnetic and it woudn't be susceptible to reversing the wiring polairity between the pins.
I have a strobe from the model airplane toy chest. Will need to put a couple of marks on the harmonic balancer for that to work. The static idle may be set too high as the idle is over 1000 RPM with the IACV/EACV control wire disconnected - Helms calls out 420 to 450 RPM with the valve disconnected.
Downloaded the Helms book and printed the engine wiring schematics for the 1992 Honda with 4-wire O2 sensor to track down the CEL fault code 41.
More to follow.......
Last edited:
INTERMISSION MUSIC: http://www.youtube.com/watch?v=hVKKHcHKYa4&feature=related
It's hypnotic watching the drummer lashing on that ride cymbal and listening to Van Morrison smokin on the harmonica........and the tone outta the hollow body guitar.....the bass player laying down a basic "Boogie Woogie" type riff (ala Stray Cats) that could be played on a full upright string bass......some good shots of him (on electric bass) picking it standing to the left of the drummer.
I gotta get this one on CD so I can listen to it while winding the ZC through the gears driving out in the boondocks.......love that British Invasion stuff!
One Sunday morning we went walkin'
down by the old grave yard
in the morning fog I look into your mystic eyes mystic eyes MYSTIC EYES.
It's hypnotic watching the drummer lashing on that ride cymbal and listening to Van Morrison smokin on the harmonica........and the tone outta the hollow body guitar.....the bass player laying down a basic "Boogie Woogie" type riff (ala Stray Cats) that could be played on a full upright string bass......some good shots of him (on electric bass) picking it standing to the left of the drummer.
I gotta get this one on CD so I can listen to it while winding the ZC through the gears driving out in the boondocks.......love that British Invasion stuff!
One Sunday morning we went walkin'
down by the old grave yard
in the morning fog I look into your mystic eyes mystic eyes MYSTIC EYES.
Last edited:
