Awluiz

Pulled old motor because two valves were shot. Got a d15b from a friend of mine, the car is an auto and it had originally the d15b7 but I swapped the one that blew the two valves in myself, it was running no issue other than valves before I pulled it, dropped the engine in, got everything hooked up, grounds all good, Ecu good, dizzy good, replaced all internals of dizzy to known good internals, since my other z6 dizzy casing was broken and I don't like that. Ecu, I have 3 p28's and a p06 that was running the car before. Main relay is good, was pulled from another car. Grounds are good sanded all down making good contact, just in case the thermostat wasn't grounded for whatever reason, ran a jumper ground to valve cover as well, because it's grounded to the chassis. Brand new battery, all fuses are good. Can't seem to get the car to send signal to the injectors. Any help is appreciated.

NotARaCist

iTrader: (1)

"Just in case the thermostat wasn't grounded for whatever reason"

What are you trying to say with that? Is there a ground bolted to the thermostat or not? If there isn't, then there's your problem. Does your CEL come on for 2 seconds when you turn the key to ON(II)?

Awluiz

Yes, it is bolted to the thermostat.
Yes it comes on for 2 seconds and turns off, I get 3 clicks from the main relay, I have spark, the engine cranks, just no injector grounding when it should.

NotARaCist

iTrader: (1)

We've dealt with a lot of stupid in the past, so don't take this as insulting, but...exactly how do you know the injectors aren't pulsing? Have you used a noid light?

Former User

Also, did you test all of the ECUs?

Do all 4 injector clips get battery voltage?

Awluiz

Yep, used a test light, constant for power, supposed to be pulsing for ground coming from the "a" connector pins in the Ecu. Numbers I don't have right now, but I know the specific ones I'm not at home with the car this second. I can check for full signal to the Ecu, but the car was literally running earlier yesterday on 2 cylinders, only thing we touched was the Ecu fuse which is back in correctly. And obviously redoing grounds and plugs and different engine. None the less, it's just a little confusing. Before I touched ANYTHING else lol. I just dropped the engine in and ran everything I was using for the time being to get it running before I changed harnesses and Ecu.

Former User

^Answer?


Does the fuel pump prime?

Is there spark at all 4 plugs?

Awluiz

I gave all Of this info in first OP lol.

I pulled Ecus from cars that were running put them back in and still running in their car, Ecus good, spark at all four plugs strong spark, brand new dizzy pretty much and fuel pump primes and stops like it should, all three proper clicks from the main relay.

Former User

You gave none of this specific information in your first post. If you disagree, go ahead and quote statements in your first post that refute it.

This is the first time you specifically answered my questions.

Have you removed the fuel rail with the injectors to verify that the injectors don't spray fuel when you crank the engine? If so, test whether ECU connector pins A23 and A24 have continuity to body ground.

Awluiz

Yes, pulled rail and attempted to get them to spray when I cranked the engine, bone dry. I'll check them in the morning to make sure. Do I connect to power and then plug into the pins to test? When I crank? Or just in the on position? Just using a test light I mean.

Former User

Use a multimeter. Do tests on the pins with key OFF.

Awluiz

Alright, what should my readings be?

Former User

Both pins should read continuity to body ground.

Awluiz

I don't have a multimeter this second, can I do it with a test light? I have the test light on power and when I poke into 24 I get a dim connection light but 23 I get nothing. When I poked into 24 at first with the key off the main relay started doing that quick clicking thing like it's not grounded well when you turn the key on.

Former User

The weak continuity at A24 and no continuity at A23 are the problem.

Awluiz

What is your best idea for my issue? I'm not the best with wiring or wiring diagrams, as I said before, earlier the day I dropped this one in, the car ran. I didn't do anything to hurt any wires, but the engine that I dropped in had been sitting for quite a while. I replaced the dizzy, as it just didn't look that good. All sensors in the dizzy are good, we just swapped everything from a brand new dizzy into a z6 shell wired everything in perfect, we've done it multiple times. I pulled a chassis ground from my other shell, and extended the thermostat ground, or better yet just added it on top of the thermostat ground wire and bolted the extension to the valve cover in attempt to get ground there, because I have the valve cover grounded to the chassis already. I have many Ecus to try, but I know they're all good. I have a couple main relays but I can take this on and put it in my other car and it will run. Is it possible it could be something in the ignition switch? I know this shell has had that messed with before, I'll drop the casing and check all wires now. Other than this, the only thing I can think of doing is swapping the harness maybe it got a short somewhere in the midst of flipping it over the fender? I'm seriously at a loss, I've done over 50 swaps in my life before and this one is racking the brain. I've had therm ground issues before, but never to the extent that I've gone to fix this one and STILL have it not work.

Former User

Are you asking how to fix the problem?

A23 and A24 ground at G101 on thermostat housing so your wire extending work may have introduced the problem.

Don't stray. Your own test results point to lack of proper continuity to body ground at A23 and A24.

Awluiz

I'm asking if you have an idea of where I should mess with first.

I extended the ground after it wasn't getting ground the first go around, just testing this and that, it wasn't a first initial thing, was just trying to get something to work.

So it wouldn't be in the ignition? Just at that specific ground? Is there any way I could do a test as to why it's not grounding at the thermostat? I've sanded the ground points for the thermostat to make sure there was a connection, but still not getting it, could it possibly be the ground wires in the harness instead?

Former User

Don't mess with anything. Be deliberate. In short, restore continuity to body ground to A23 and A24.

What is the rationale for this idea? How is grounding at A23/A24 related to the ignition switch?


Yes. That's what your test results indicate, right?

Depin A23 and A24 from ECU connector A. Inspect them. If the pins look fine, then cut the wires from the pins and solder new wires to the pins. Run the wires to G101.

tony_2018

A23 and A24 is at the ecu, which means your ecu isn't seeing that ground connection, g101 as Ron stated. Try grounding A23/A24 from the ecu side.

Ron,

off topic a bit. Looking at a connection from A23 going to some square box, looks like a 'C'. What is that?

Former User

Tony, can you post a pic?

tony_2018

Former User

Haha...

It means continued on next page where C is shown. The specific answer is the ground wire for the D15Z1 LAF sensor.

tony_2018

Got it