D16z6 misfire? Help me get this thing running!
 

Ok I got a 92 civic dx with a z6 swap. I bought it off this kid and its running bad, like misfiring and it's idiling high. I look at the timing belt and is seems loose so I figure the tensioner is bad and maybe made it skip a tooth. So I replace the plugs and wires and do a timing belt and water pump and tensioner. Also The car was running off a p06 ecu and I swapped a p28 on it. Well I go to start the car and it's running even more rough than before. Low RPM misfire chuggle barley running. Check the timing and it's good, check the wires and they are correct. So i figure i'll try putting the p06 back in it, i do and it runs high rough idle with a surge around 2500-3500 RPM. What could be wrong with this thing? I tried getting codes and it dosent seem to want to work. Thanks in advance for the help.

Have you checked the distributor cap and rotor?

What are the cylinder compressions?

Is the fuel pressure good?

******Was the CEL bulb removed or disconnected?

Yep, I checked the rotor and cap, both good. Newer looking so I don't think thats an issue. I know im getting fuel because i pulled the plugs after starting it and letting it run for a few seconds and the plugs were wet with fuel. I'll compression test tomorrow and let you know the readings. The CEL bulb works because it passes the bulb check with key on and it flashes when the car is running due to the severe misfire.

Please give more information. OBDII ECUs but not OBDI ECUs throw misfire CEL codes. For OBDII Civics (e.g. 6th generation), a blinking CEL indicates misfiring severe enough to damage/destroy the catalytic converter. The stock Z6 engine came with an OBDI ECU, which would not recognize engine misfiring. Is the p28 ECU OBDII? If it is OBDI, then the blinking CEL is very puzzling. It might possibly be indicating a CEL code (rather than indicating misfire) due to a short circuit in the CEL service connector circuit.

Ah, I'm not sure, I assumed all p28's were obd1. How do you tell if it's obd1 or 2?

There was apparently an OBDII p28 ECU made for the Del Sol:

http://www.superhonda.com/forum/f99/...28-ecu-244130/

Haha I was looking around and I read that exact thread like an hour ago. I think the connectors are different though but again i'm not sure. There is no conversion harness on my car and the ecu plugs right in so I think it's obd1. I'm going to go compression test it right now. This kids story is that it was running good up untill a few months ago, it has had the swap in it for almost a year and it was fine. Then he said it started running rough and misfiring and he parked it and just started doing body work to it untill he got sick of it and wanted to sell the car. If worse come to worse I could just put a new motor in it for like 200 bucks but I have the suspision that it's maybe some electrical issue. I'll be back in a bit with those compression test readings.

So when the engine is running, you say that the CEL is blinking. Does the blinking seem to be in the form of a code? Or is it just a steady continuous blink?

What happens when you jumper wire the service connector? Does the CEL stay ON steady, does it blink, or is it OFF?

It seems to be a steady blink but i don't let the car run long enough to tell for sure, I'm afraid it'll hurt the motor the way its running. But when I jumper it, it comes on with key on but then goes off and does nothing.

For this test, did you turn the ignition key to ON(II) with the connector jumped?

Does the same thing happen without the service connector jumped when you turn the ignition key to ON(II)?

This indicates CEL code 0, which is a problem with either the ECU or the associated service connector circuitry (see Chapter 11 of the 92-95 Civic service manual at link in my signature).

If the compression test fails, it could just be that someone has adjusted a valve too tight.

Make sure that all 4 cylinders are working by disconnecting the fuel injectors one at a time. The plugs should not be wet with fuel after you run the engine and turn it off. That would seem to mean that way too much fuel is going in, perhaps the pressure is too high. The little hose on the back of the fuel pressure regulator needs to be connected to the intake manifold vacuum. (There should not be any fuel in that hose, if there is, the regulator is bad).

Compression test results...

Cyl 4 Cyl 3 Cyl 2 Cyl 1
180 154 152 155

If the car "runs" for a little (like 15 seconds) and I pull the plugs out, theyre all black and # two and three were wet with gas.

Cylinders 1-3 have low compression. This could be due to engine damage or flooding. Do you have bright bluish spark at all four plugs?

I have yet to test the quality of the spark.

Ok update... Spark was good so I decided to take the motor apart and rebuild it. New rotating assembly, crank, rods, pistons, rings, honed the block and cleaned the head. New valve seals. So the motor is running good now. Problem is now, It doesent seem like the clutch is engaging. I can push the clutch in and put it in first and let the clutch out and nothing happens but if I give it gas with in in gear, the speedometer operates, I can do the same in 2nd-5th. Give it gas and the speedo works like the wheels are spinning and it sounds like the tranny is spinning but no power is getting to the wheels. Could I have a blown diff or something? The clutch seems to work ok. I can see the slave cylnder move the clutch fork when the pedal is depressed but the wheels are not moving. Any Ideas? Before now I have not been able to test to see if the car even moved (under it's own power) when I got it so I'm not sure if it's something I did taking the motor out or if it's a problem that was present before but I'm only now finding out.

Have you checked both drive axles?

Popped out of the trans? No i havent checked that.