Obd0 - Obd 1 conversion - no spark

rti intrac

I have done a obd1 conversion on my wagon.

I have made up a conversion harness. I am 100% i have got it right.
I have injection pulse and the fuel pump is priming as normal. I have checked for trouble codes and only have 21 VTEC Solenoid Valve Defective circuit or unplugged/defective solenoid valve as it I havent run the wire yet.

I have traced the ignitor wire in the harness and it is in the right place, at the dizzy plug I have 10 volts with the ignition on. I connected my multimeter and I am getting a pulse on the Ignitor wire. I am using a repinned obd0 dizzy. that is 100% as it works when my obd0 computer is connected.

I Have tried with a seperate obd1 computer with the same results

So where do I go from here?

I am stuck for ideas

ricefighter

have you tried putting an obd1 dizzy? i suspect thats the culprit. i know people here use obd1 dizzy when converting to obd1. just my 0.02cents.



wagon......................4ever......................

rti intrac

I have read that you can use a obd0 dizzy, I have tried a obd1 dizzy with the same result

Jaker

In the USDM cars, the OBD0 distributor only has 16 segments in the reluctor, whereas the OBD1 and OBD2 have 24 segments. This can lead to starting difficulties and the engine will certainly not run correctly even if it does start. However, since you mention having tried an OBD1 (know to be working correctly?) this is likely not the problem.

Some OBD0 to OBD1 conversion harnesses are constructed to allow color for color wiring of the distributor when installing an OBD1 dizzy, and other are made so things are OEM wiring (sensor for sensor according to how Honda intended it to be).

I suspect that you might not have it wired properly, and there's a pretty simple test to check for that. Simply swap 2 wires on your adapter harness. You need to move the wire at B15 on the OBD1 plug to B11 and vice versa.

The B plug is obviously the middle plug, and the wires are numbered with the top of the plug being where the locking tab is, and the #1 wire being top left when facing the back side of the plug where the wires actually go in (see 1st photo). #2 would be directly below #1, and #15 on the B plug is the top right wire.

Getting the pins out of the plug can be a little tricky. There is a locking bar along the top and bottom of the connector (see photo 2 and 3) that must be lifted before attempting to remove the pins. Once the bar is lifted, you can insert a small sharp extraction tool (I used dental pics that I purchased from a hobby supply store) into the front side of the connector, just above the pin you wish to remove. Angle the tool slightly downwards with a small amount of pressure, and push it back with light force. Do not pull on the wire until you have inserted the tool correctly, or the tension on the locking tab will make it much more difficult to release. Voila, the wire should be released now, and free to move to it's new location. When inserting the wires, the crimp side of the wire terminal is the top, and the flat side is the bottom.

rti intrac

Awesome, thanks for that Jaker!! Ill give that a shot. The Obd1 Distributor was working when I removed the engine from the car

vtecn8ive

You need obd1 dizzy. I learned that before.

obdo reads a different pulse than obd1.

Off the top of my head make sure you have the white wire going to the right one (I know when converting the wires there was 2 white wires) Like I said this is completely off the top of my head.

What engine harness are you using?

rti intrac

I am using the stock mpfi injectiopn harness and sensors with a adaptor harness at the ecu end to convert to obd1

vtecn8ive

Just making sure you are not using a HF wiring harness. That was the cause of one of my obdo-1 conversions.

Well you need a obd1 dizzy.

I've done quite a few obdo-obd1 (I do the wiring myself) conversions so if its still an issue after you put an obd1 dizzy in I'd double check your dizzy wiring.

May sound goofy, but did you make sure your distributor has the rotor in it or the screw in it?

Haydz

We don't get the HF here AFAIK - we got a 1.3L carburettored motor in its place.

He started with Wagon MPFI harness i think?

rti intrac

Found I was missing the little spring that goes between the coil and the cap. I replaced that and guess what? it still doesnt effing work!! now its time to trace the wiring and try swapping B15 and B11 around. The Harness is a matching colour harness.

bastard!! I have wired the obd0 plug up in mirror to what it actually is, its damn confusing being dyslexic and trying to figure out which side of the plug is which haha. I have fixed one plug but must not of done the other one

vtecn8ive

Try being colorblind and having a background with numerous successful wiring conversions (dpfi-mpfi-obdo-obd1-vtec-vtec-e) Believe it or not the conversion harnesses are that difficult to make just time consuming.

ok im rambling a bit. good luck.

rti intrac

Oh my god, I feel like an idiot, I had two wires swapped around. Swapped them around adn it started first pop. only got coded 21 & 22 as I havent connected the vtec pressure witch or solenoid up yet

vtecn8ive

Curious which wires it was?

rti intrac

B17 and B3 haha, ignitor and the A/c clutch relay, I had extended the a/c wire using a blue wire which is what confused me