everlight44

Hello,

I apologize if this is difficult to understand... I'm new to battling electrical problems.

Kind of a strange question for you gurus out there... I'm trying to check the continuity of my distributor in the engine harness. Interestingly there is continuity in the upper harness between all the pins (from distributor plug on engine harness to the upper connector of the engine harness that goes down to the ECU), but if I try and check for continuity between the upper harness and ECU connectors/plugs, I cannot find continuity any where. I've tried the CYP, TDC, MAP, and ICM sensors with no luck, so I find it hard to believe that the whole harness went bad.

Are there special requirements for checking the continuity between the upper and lower engine harness? I'm hesitant to turn my ignition on to the "2" setting else I might fry my tester.

Or is this even possible? I just simply cannot get any continuity between the ICM and the ECU pins.


Thanks,

Sean

HondaHeddie

silly question
the wire colors are the same on both ends of the harness you are checking, right?

everlight44

Yup :-/

omgwtfbbq

power to the car won't fry your multimeter. Are you pulling the connector from the ECM and testing it at the connector? If you are, make sure you have a good probes for teh connector. Those pins are buried and regular multimeter leads won't fully contact the connector.

Did you check for continuity between the line and the ground? That'll tell you if the short is grounded at any point.

I'm guessing your ecu is in limp mode, or the car doesn't start at all. The manual states the continuity should be between 350-700 ohms for all the dizzy sensors (ckp, tdc, etc.). Make sure that where you do have continuity, it is within spec.

Also, and even i've done this before, make sure everything is plugged in snug before testing your wires (minus the ECU, it doesnt need to be plugged in for continuity checks with wiring harnesses). I've gone crazy checking stuff when wires arent even plugged in correctly.

Hopefully that helped out. post if you got any more questions.

omgwtfbbq

testing process:

test wires at dizzy, if you have continuity, plug in connector and test at connector tower. If you have continuity, plug in all connectors in engine harness, and test between the appropriate pins on ecu. If you have no conitunity there, then you have a break in your harness between the ecu plug, and the plug that connects to the engine harness. If you have full continuity there, I would try swapping the ecu with someone who has the same car as you, and see if you still have the same problem.

Also, you may want to test on the firewall side harness. (you will need to peirce the wires to test. You may have a bad connection at that connector).

everlight44

Thanks a bunch man... I was thinking that maybe my probe wasn't long enough, so I will test that tomorrow. I did the full distributor testing process per the service manual I have and it passed, so I'm wondering what is going on... How do you get the ECU out of limp mode?

Unfortunately the car does not start and doesn't even sound like it is firing... it does turn over but very slowly compared to a normal cranking sound. I pulled a spark plug after trying to start it and I smell gas, so I don't think that is the problem. I've checked all the body grounds... is it possible that the starter is the culprit? I changed that awhile back with another one I had and it ran fine until I tried changing the distributor with my new one, but now the car doesn't start at all... I just don't know what is going on.

omgwtfbbq

If the starter was bad, it wouldn't crank over at all. I am guessing you got some CEL's pulled to suspect the dizzy. I had the same problem...the difference was, my car came with the harness cut on the firewall side of the plugs...meaning I had to cut the connectors from another car, and solder in each wire. Considering I did almost 200 wires, I knew i had to have messed up somewhere. But, I had to test all the way to the ECU to discover that I had a faulty solder on one harness. I had continuity at the dizzy, and the wire harness from the dizzy to the tower, but no cont. at the plugs at the ECU.

After fixing the wire, I still didn't have cont. at the ECU...after going crazy for a little bit, I used probes to make sure that I had a good connection at the plug, and then it tested out ok. car runs great, no CEL's, and no more limp mode.

omgwtfbbq

which manual do you have, BTW? I have a manual thats better than Haynes and Chiltons, I could email you the pages for the TDC testing and stuff to help you out if you need. Its for 94-95 Integras (including GSR)

everlight44

I have the 98-01 integra service manual... it's about 1600 pages long and has pretty much everything. The wiring is slightly different, but I have pin-outs of the ECU and distributor. I'm downloading some more manuals now, but if you could fire what you have to everlight389@gmail.com it would be greatly appreciated.

I actually pulled the distributor because the old one's bearing was going bad, but I've had ignition problems with this car for a long time. The MFI went first (intermittent crank but no starts), then the starter, the distributor (replacement I RMA'd), and now I put on the new distributor and the car doesn't start at all with either the new distributor or working old one. Both ones are 100% with voltage, continuity, etc... so it has to be wiring somewhere.

The reason I say the starter is the one I put in there had 150k miles on it, and the manual I have says the car should crank at 100rpm+ when trying to start. It is nowhere close to that, but that could be due to a lack of spark. At this point I'm honestly guessing :-/

Thanks