Let me preface this by saying that I am not a rookie when it comes to vehicles or Hondas. This just happens to be an issue I cannot seem to figure out, so here is my issue.

I have a 1992 Honda Civic CX chassis with a transplanted D16Y7 motor and transmission running a p05 ecu. The car was running fine and was driving fine before I brought it in the garage to do some upgrades and modifications. They are brake and fuel line tuck and upgraded wheels and suspension. I also took on the task of doing my own wire tuck. (I didnt want to spend $500 on a custom harness).

This is where I have run into an issue that is mind boggling to say the least. When I turn the key over I get my door chimes like I should and I have power and signal to the starter as I should. I also have headlights and turn signals. What I do not have is power to the fuel pump and other components.

I have tested the grounds at the thermostat housing and they show to be good grounds. I have also tested the main relay under the driver side of the dash and as most other Honda heads, have multiple ones in my tool box and have tried all of those as well and still same conclusion, I am not getting power to it where I should be.

I know this is all very vague and not much to start with, at least to me but then again I have been staring at the same wiring for the last few months. Just a side note, I do have over 20 hours in the new wire harness. It is not thrown together, it was all carefully depinned with notes and wiring diagrams and checking ohms and all that good stuff and then soldered, heat shrunk and wrapped back in a nylon woven wrap.

I am at the mercy of the board and if there is anyone that can help me get this car started so that I can get it out of the garage and enjoy it the way it was built to I will be in your debt and will even repay you somehow someway.

If there are any questions that I can answer to help someone who might be able to help I will do all I can. Thank you in advance and lets get this Honda back on the road!!!

 

Well, I will state the stepped back view. The problem is not with any part of the wiring you didn't touch.

That being said, you get the very fine pleasure of testing the majority of the wires you did touch to verify the right wire is to the right pin etc.

Somewhere along the lines you lost continuity between key connectors somewhere.

Being you have lights and chimes, I would be focusing on the ignition and relay wiring that you changed up. Testing for continuity between connectors, tracing the full path. I'm sure one of them is not completing it's circuit, now it's to find it.

 

p05 shouldn't be running the y7. at all.

 

Aside from this ^^ being true, what have you checked for fuses? Esp the 15A ECU fuse under the hood.

 

Yes I definitely thought it was strange when I pulled the ECU and saw it was a P05. But its been in the car since I bought it and ran and drove fine.

Yes I have checked the fuses and the fuse box that was under the hood and they are all still good.

I will check the continuity between the harness I depinned.

 

I forgot to add that I am still obd1 on everything but the motor itself.

 

Simple stuff first, unplug the PGM-FI Main Relay and test for the 3 powers in the plug , you should have...

1 12V+ constant, [hot at all times]
2 12V+ switched, [hot in run and start]
3 12V+ switched, [hot only when cranking to start]

Make sure the black lead has full continuity to chassis ground.

Let me know what you find. 94

 

It does sound a bit like a bad ground issue. OP, check your grounds in the engine bay. Clean them up.

 

In to see the process. Me likes how this is starting (KISS method) when wild issue like this happens.

 

Unplug main relay.

Turn key to ON(II).

Use a piece of wire to jump pin 5 to 7. Does pump run?

Use a piece of wire to jump pin 1 to 7. Does pump run?

 

The pump ran when I jumped both of those. I also cleaned all the grounds in the engine bay and checked for resistance and im good there on all of those.

 

1 had 12v constant like stated.
2 had no power in run.
3 had no power in run or when cranking.

 

Plug the main relay connector into the main relay.

Turn key OFF.

Unplug ECU connector A.

Turn key to ON(II).

Use a jumper wire to ground the Grn/Yel wire at pin A7 in ECU connector A to the metal frame under the dash.

Does the fuel pump run as long as pin A7 is grounded?

 

Based on your results from the tests that I suggested, you probably measured voltage at the wrong main relay connector pins.

 

Fuel pump did not come on at all when doing the test with connecor A.


Also on a side note and completely but somewhat related, does anyone know the proper way to bench test a main relay for obd1. I found the test for 91 model cars but as stated in other threads, there is no number 4.

 

There are several possible causes for your problem, one of which is a bad main relay.

 

I went through my stash of main relays and found one that is good according to the test. I went back and plugged it up and tested the a7, the green wire with the yellow stripe, 4th wire over on the top of the A plug and I have no sound coming from the fuel pump.

So yes I am puzzled.

 

Also just wanting to retest the connector at the main relay like in the previous procedure, the following are my results:

#1 - constant 12v
#2 - no voltage present when in run
#3 - no voltage present when cranking/turning over
#4 - no voltage ever
#5 - 12v present when in run
#6-8 - no voltage present ever

 

Well, I guess I am on my own from here on out. I will continue working on it and posting my results as I go on. Thanks for those who did attempt to help me with the issue.

 

Please have patience. @RonJ is a very busy individual, his replies may not always be instantaneous, however they will follow and be with sound advise and insight.

 

I bought a b swap with a p06 (d series ecu) and d series dizzy. It "ran and idled" fine too, had good power even, but in reality in some places the map had a 29 degree timing difference!

I suggest chipping it or getting the proper ecu. I doubt that relates to your particular issue but it needs to be said. I can burn you a chip if you need, pm me.

What the other members said hit it on the nose. Are you able to test with the/an original harness at all? While the problem is very likely something you changed, sometimes actual verification is what people need to proceed to solve the problem.

I only skimmed. Have you tried giving +12v to the FP directly and see if it fires?

You need to not just test the voltage in each connector in the diagram posted but check that each of those pins has continuity with the listed destination - follow the instructions directly and report back.

Do you have a service manual? This is not something you should probably be attempting. I bet there are links on this site to some if you search, I would post one but I don't feel like searching and am not sure if it's against the rules or not..? Just Google 92-95 civic service manual, you'll find a pdf. The pdf will have all the pages other members have posted along with wiring diagrams, schematics and troubleshooting proceedures!

 

Thanks TomCat.

Redo the 5-7 and 1-7 jump tests, as well as the A7 ground test. Post whether the fuel pump runs for any of the tests.

 

If my last post was sounded whiny I want to apologize. My gf is upset that this car is not finished yet and the guys where were supposed to help me here in Memphis havent had time. I just want to apologize to all that have helped me so far. My deepest apologies and my most sincere, THANK YOU!

 

The fuel pump does run on 5-7 and 1-7 but does not run when I ground A7.

 

Inspect the main relay for bad solder joints.

MarkLamond.co.uk - PGM-Fi - Main Relay

http://techauto.awardspace.com/mainrelay.html

Also clean and tighten the G101 ground attached to the thermostat housing.