Need ZC Help

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pasouza

New Member
Have a 91 DX Wagon which I recently swapped the stock D15B2 for a used ZC that had been in a wrecked 91 CRX Si. Modified stock harness and took what was needed out of CRX (e.g., injector resistor, ECU, etc.) and put them in DX. Put in new timing belt, clutch, fuel pump, fuel filter, etc. as part of swap. Swap went great and the engine ran splendidly in the DX.

After 40 miles, the car was driven one day, parked, and wouldn't start later. After cranking on it the ECU would blink once for ECU on and then repeat through 20 short blinks followed by a pause and then 20 short blinks (over and over). Then found car would run if 1/4+ throttle was applied on startup. Engine will run rough and will not idle. No backfire.

Note: after getting engine to start and at least run, the ECU on next check (ignition on but not cranking starter) blinks once for power on and does not blink at all afterward. Found that everytime it is cranked but does not start the ECU will do the 20 blink thing. If you actually get engine to run, it doesn't.

Initially thought timing belt jumped but that was not it.

Checked for spark.. Found plugs worn and #4 fouled. Replaced plugs. Engine will start with throttle applied and seems to start easier but still very rough and no idle (just dies).

Moved to distributor. Have components from D15B2 distributor (which had been replaced in 97) and swapped out rotor, coil, upper pickup, and chip (hitachi I think - not sure what it does). No appreciable change in running. Did not swap out lower pickup because I couldn't get the pin out of upper pickup rotor to remove plate to get at it.

Also note that when plugs are pulled, they are a little wet and definitely smell of gas. This is what led me to think distributor and ignition issue.

Could this be a distributor issue where I need to just by a new one? I didn't replace distributor cap because it looks fine. Could this be clogged injectors? TPS or CPS?

Any suggestions would be greatly appreciated.
 
Look in our reference section for ECU codes. The light shouldn't blink 20 straight times in a row, but maybe the older ones do (don't remember). Check the reference section. ;)

Did you do all the wiring correctly? The JDM DOHC ZC requires a pair of wires to be swapped compared to USDM. I think... pretty sure. Again, it's been a while. If you check "DPFI to MPFI conversion" here and around Google, you should find reference to it. Doublecheck everything.
 
The swap went great. All rewiring is correct as the engine ran great. Didn't rev it too high, but at least up to 6000. Drove it off and on for a couple of weeks.. been waiting to put new tires on front since they sat on car in back yard for 6 years. I have checked on the engine codes for the PM6 ECU.. Nothing at all comes up for what I would get when cranking without actually starting. Just oddity I think.
 
is this a DOHC ZC or SOHC ZC? - code 20 is the Electric Load Detector and is usually a problem with the alternator not charging enough - check your fuel pressure
 
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the ecu should still have the capability to run with at least 9 volts, fact that the engine cranks over probably means he has enough voltage for the ecu to function. Something gives me the feeling you may have a coil malfunction causing backfeed, high voltages going the wrong way (code 20 possible cause), or an igniter failure improperly controlling the coil.

Coil and igniter failures are very common. If you can find component tests within the manual for your old engine, should be the same as the new engine.

of course having access to known good ones to simply plug and play would be a much easier way to diagnose it, unless the test parts are also bad rofl (happened to me once). Because of the known failure rate of igniters, I literally have a new one in my glove box as a spare in the event it fails on me down the road.
 
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So I did do something smart. I did swap out the ignitor, coil, upper pickup, rotor, and finally cap (had to modify the key slot) from the D15B2 distributor. Note that the D15B2 distributor was put in around 97 and probably had less than 40K miles before I busted a piston rod. These changes had no effect. Engine will still start with throttle applied on crank and since it is mighty cold out it will actually idle if not horribly.

An aswer to a question above. It is a DOHC ZC using the PM6 ECU from the 91 CRX the engine came out of.

So, I get it idling and start pulling plug wires. I can actually pull cylinders 1, 2, and 3 and the engine keeps chugging. It seems to amazingly run on one cylinder. I then though spark plug wires. So I took cylinder 3 wire and put it on 4, put 1 and 2 back in distributor as well and cranked it up. Still runs, albeit like crap. Seems not to be wire 3. I don't know enough about the dizzy but the only component I haven't swappeds is the lower pickup (assume this is the intake cam shaft sensor) and what looks like a capacitor on the outside of the distributor which I think is wired to the coil. Perhaps the older components I swapped out were bad too. I don't know but have no reason to believe so since all they did was sit in the car for 6 years without being used.

Next step to do a wholesale replacement of dizzy?
Could this be weak ground?
 
Time to get your volt meter out and perform the testing per the book. Also if you suspect a lack of spark, I recommend unpluging all your injectors before performing any further testing, otherwise you may turn your catalytic converter into a solid wall with no place for exhaust to pass, preventing exhaust from leaving the cylender, preventing fresh air from coming in, and loverloading the combustion chamber with a super rich fuel mixture where the levels of oxygen are already gone. Gas engines require fuel, spark, oxygen, and compression to work properly. Usualy crank no-starts are checked in that order. All cylenders are loaded with fuel. That doesn't nessesarily mean that fuel is OK. If for any reason your regulator or return line is stopped, pushing 70psi to your injectors, it could be flooding the crap out of it. Should be 30-40. Need to know if you have spark at all plugs and that your timing for cylender one is acurate. Need to know if your exhaust is flowing, possibly removing the oxygen sensor temporarily will give you an idea, and finally that your compression is even through all cylenders. That you don't have water in your oil, or oil in your water, that your timing belt is on correctly and hasnt skipped a tooth. Low manifold vaccum or consistant drop in compression through all cylenders can be signs of that. Signs of a blown head gasket can also put fuel or exhaust vapors into the oil and coolant and cause a rough cranking period. Cover your bases before you new parts on.

Forgot to mention the rare situation of fuel contamination or sabatage. With your plug out and engine hot, turning the key on should build pressure in the fuel rail but should never let and fuel spray into it. If you have injectors that are gushing out gas from having dirty or contaminated injectors, they will usualy drip out when they are supposed to be shut. Having plugs out should give you some vapors after turning the key on if thats the case. And those situations almost always garuntee a plugged cat. In fact at this point regardless of what the real root cause of your problem is, you probably have additional damage to the cat at this point already.
 
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Well, let's see. Checked timing belt. It was newly replaced by me and timed when I did the swap. Belt is fine and correct. Checked spark and all sparked but plugs were worn. Did not spark test in low light to see just how blue it was on each wire (could be weak spark on all cylinders but 4 seems to fire obviously). Will check cylinders to see if injectors are stuck in open position gushing gas.

Engine was running great. I shut it off and 3 hours later it wouldn't run properly. Seems like an electrical problem to me. I have a had time with a blown gasket. No water in oil or vice versa. I know what that looks like and how it behaves (I have a 94 3.8L Taurus - I know what a blown head gasket is like and how painful they are to replace on the Taurus). I've had water both get into intake and into oil with that POS (but hey.. someone gave me the car).

The cat I am not concerned about as long as it lets exhaust out without resistance. I live in Tennessee. Heck, we don't have car inspections let alone emission inspections. It's 17 years old at this point anyway and it won't get replaced unless I absolutely have to. I really don't think it is overloaded at this point. It's not like I have cranked or run it the way it is. My boys and I pushed it out of the driveway and to the back yard when it wouldn't start and there I have done what little crank testing I have done so far.
 
Raw fuel causes them to break apart into poweder that clogs the cat's grid. But ya I guess if you don't have inspections and don't care about pollution, you could unbolt it and shove a broom handle through it, if it is in fact clogged causing your problem. You would probably hear a lot of intake popping.

Ya them tauruses used to have a recall for head gaskets, big pain in the patooter.
 
are the spark plug wires in the correct location on the distributor cap?

zcfiringorder2-1.jpg
 
Unfortunately they are. I thought wires that's why I swapped the wire on 3 to 4 and started the engine again. It will run on one cylinder.

Pulled plugs and turned ignition to on. Fuel pump runs for 2 seconds and then stops. No fuel leaking into any of the cylinders so I am pretty sure it's not a flooding issue due to leaking injectors. Fuel is definitely getting to cylinders 1-3 as the spark plugs are definitely wet and un-burnt fuel does seep from the exhaust manifold.

Pulled out the volt meter and went after the injector resistor. It's in spec. Coil resistance is fine. Resistance on distributor wiring pins a little low (340) versus Haynes manual spec that says 350-500.

Will swap out main relay since I have one on hand but I am positive that just couldn't be it.

I'm thinking there is some voltage leakage in the distributor due to aging wires as the insulation is a bit brittle. I'm betting the distributor has over 140K miles on it. The engine certainly has some miles on it but it ran like a sewing machine in the CRX and exactly the same in the DX Wagon after the swap.

Bah.. at a loss and like sneaky suggested, a little concerned about pouring money into parts that don't solve the problem.
 
Lookin good there JLI, ecus are overrated lol. I hope you got filters in them things. Battery location looks real interesting too.

Are you able to verify the timing while its running like this? Using plug wire #1 as indicated in that prodided pic.
 
Yes. That's exactly where I had them and have made sure where they are supposed to go each time I took the distributor off to swap parts. The spark just seems weak on all cylinders but for some reason cylinder 4 fires. Playing the plugs in and out seems to get 1 and 3 to try to fire at times but nothing better than a brief smoothing of the run.

I screwed around with the timing belt at first trouble shooting because it looked like it had jumped. I only have time to work on it once or twice on the weekends and one or two nights a week so somethings I don't recall too well what all I have tried. My memory serves me it just looked like it had jumped some teeth but now I don't know. Going to do a compression test to put that out of the way. Hopefully it didn't jump and cranking it the first... or twentieth time since then didn't result in bent valves. Will let you all know.

Thanks for keeping with me on this.
 
Well I must have done this one to myself screwing around with the timing belt. I am pretty sure at one point I cranked it with belt on 360 degrees out on the crankshaft. Can you say dumbass!

Compression test gives 180 psi on cylinders 1 and 4 and zero compression on cylinders 2 and 3. I am going to pull the head but I am pretty confident I am going to find some bent valves. I have searched the web and cannot find anything for the ZC valve parts needed. Anyone know which valves I will need to purchase should I find some damaged valves?
 
Well I must have done this one to myself screwing around with the timing belt. I am pretty sure at one point I cranked it with belt on 360 degrees out on the crankshaft. Can you say dumbass!

Compression test gives 180 psi on cylinders 1 and 4 and zero compression on cylinders 2 and 3. I am going to pull the head but I am pretty confident I am going to find some bent valves. I have searched the web and cannot find anything for the ZC valve parts needed. Anyone know which valves I will need to purchase should I find some damaged valves?
all valves and valve train parts are 88-89 Integra D16A1
 
Thanks a bunch. Head will come off tonight if it's not too cold that I can't stand working out in it longer than an hour or so.
 
From what I understand, pretty much all Honda engines are interference. A timing belt jumping some teeth on either of the cams on the DOHC would result in bent intake or exhaust valves or both. What bothers me is that I get great compression on 1 and 4 and nothing at all on 2 and 3. I got started pulling the head last night but the cold eventually got to me.

Question: The front motor mount (timing belt side of motor) appears to have one bolt in the head. The lower two appear to go to the block. Is this correct and I shouldn't have raise and support the motor to get the head off?
 
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