Ae86 gts not starting after I changed chassis harness (4age bluetop)(redtop harness)

[project-d]

Hey guys I guess the tittle says it all but I have a blue top and I got a black top harness off a guy on kijiji because my ecu pin was all cut up...

The car starts but within a seccond or two it just dies. My friend vic and Ken came over to give me a hand and we diagnosed that the motor isn't getting any fuel. When I tried spraying brake cleaner in the intake (because i had nothing else) while my friend cranked it, the car ran for a little while... So after trying all off this stuff I'm pritty sure it's not getting any fuel... Or the injectors are not fireing ... But I know for sure that the fuel pump is good and so are the injectors.

Does any one have any ideas? Thoughts? Similar experiences? Or have seen or head about this before ? If so, please Lemi know !!

Thanks DK!

[Trigger Happy]

Run 12v to the fuel pump, try starting it again

[cam_132]

2 things you can do, 1, grab a long screw driver, and stick it on the injector, put your ear up to it and use it like a stethoscope. if you hear a loud clicking injectors are firing. if not, then there is your problem, track it down and solve. could be a bad injector ground. also you can do what Trigger happy says and apply 12v to the pump and crank...

[BARKER]

Sounds like you need to connect the ground for your AFM. It's located on the driver's side of the engine bay. It's the big dirty yellowish one in the center of this pic.



(I stole this image from somone on club4ag, but you wouldn't believe how many times I've used it as a reference)

I hope this helps.

[Bigbird]

Your circuit open relay gets power from the starter solenoid when cranking and powers the fuel pump. when it's running, you get power from the AFM to run the pump. Jump the B+ and Fp pins in the 17 pin connector and your car should fire right up. Check on your wiring diagram for the wire between the COR and the AFM and repair it.

[Jehuty77]

@BigBird Which 17pn connector?

Make sure all your grounds are good




You can also try running 12V directly to your fuel pump, I know a few people who had to do this.

[Rastaracer]

Where do you find such awesome diagrams?

[VickersGTS]

word. those are sick.

[neil85ae86]

ya, the fuel pump is definitely getting cut, from memory it's behaving exactly the same as if you tried to run it without the AFM connected to the intake (if the flap doesn't stay open power to fp is cut.). I haven't ran with an AFM in many years but it sorta rings a bell.

hopefully it's just a ground

good luck

Neil

[project-d]

Sounds like you need to connect the ground for your AFM. It's located on the driver's side of the engine bay. It's the big dirty yellowish one in the center of this pic.



(I stole this image from somone on club4ag, but you wouldn't believe how many times I've used it as a reference)

I hope this helps.

Hey I already have that one plugs in but the one behind it is hooked up to power... I've been told that it is a ground and from the looks of ur pik it looks like a ground aswell ... I know the fuel pump is working but I don't know where the injector ground is located ( like from where to where it goes )

[Duy-]

ive never seen one car have so much trouble running aspirated stock. why are you running a redtop harness? is it a redtop smallport harness? was there a performance gain i didnt know about? did it come from an ae86 or an ae92?

[JOshua a]

ive never seen one car have so much trouble running aspirated stock. why are you running a redtop harness? is it a redtop smallport harness? was there a performance gain i didnt know about? did it come from an ae86 or an ae92?

The ground is on the intake itself. You will see underneath where the injectors are. Just follow the harness. You need to check your timing aswell. It's WAY off. If you need a hand let me know.

It's a stock bluetop. But half the parts that were on it before were from a GZE. The wiring is literally a rats nest or just hacked! I recommend changing all the wiring including the body harness in the engine bay.

[project-d]

The ground is on the intake itself. You will see underneath where the injectors are. Just follow the harness. You need to check your timing aswell. It's WAY off. If you need a hand let me know.

It's a stock bluetop. But half the parts that were on it before were from a GZE. The wiring is literally a rats nest or just hacked! I recommend changing all the wiring including the body harness in the engine bay.

The guy I got it from said it came from an ae86 redtop but the chassis harness are exactly the same and not one of my wires in the engine bay is cut so I wanna try to get my timing done and check the grounds and the wireing around the starter .. Lol . I think the harness is fine it's just I gotta sort out where the wires go . ... I kinda think my timings okay right now too but it's best to make sure... I am running a redtop harness becUse I couldn't find a bluetop one but they are the same and yes it is a redtop small port , there were no performance gains becUse I changed the harness because the ecu cone for wires were cut .. If someone could take a couple piks of there engine bay I would really apreciate it!

[BARKER]

Hey I already have that one plugs in but the one behind it is hooked up to power... I've been told that it is a ground and from the looks of ur pik it looks like a ground aswell ... I know the fuel pump is working but I don't know where the injector ground is located ( like from where to where it goes )

If your car is starting for a few seconds though... your injectors are clearly grounded because the car is starting!

I'd try what neil85 suggested. Wedge the afm flapper door open and see if the car will start and run.

Out of curioustiy... how do you know the fuel pump is running? Listening to the pump prime (when you turn the key on) doesn't necessarily mean that it's going to function as it should.

When you start it, does it run normal for like 3-5 seconds and then just shut off completely?

[project-d]

If your car is starting for a few seconds though... your injectors are clearly grounded because the car is starting!

I'd try what neil85 suggested. Wedge the afm flapper door open and see if the car will start and run.

Out of curioustiy... how do you know the fuel pump is running? Listening to the pump prime (when you turn the key on) doesn't necessarily mean that it's going to function as it should.

When you start it, does it run normal for like 3-5 seconds and then just shut off completely?

I will try what neil85 said today and keep you guys updated. I know the fuel pump is working because before I changed the harness it was working.. I will still try and give 12 Volts to it today ... I've been so busy lately but today I'm free so I will work on my car. And when I start it the car starts for literally like 2 second then shuts off ... 3-5 seconds is to long...

[BARKER]

The fuel pump is probably fine. What I'm saying is that because of other things hooked up wrong, it may not be getting the signal from the AFM to keep running after initial startup.

[Jehuty77]

Someone local help him out.

Use the diagrams I posted and make sure everything is plugged in properly and you AFM is plugged in and sealed.

[project-d]

Sorry guys I took another look at the pik and I think my car is hooked up fine :$
I wanted to check if I had fuel presure so I opened the line that goes from the fuel filter to the fuel rail but I broke the line I'm trying to get another one

[Dentman]

You can test for fuel flow by turning the key to the run position and pushing open the AFM door. Listen to the fuel rail and you will hear fuel pulsing in the rail if the fuel pump and circuit are working. If not, then you have a FP relay to IGN that is not wired up right, as was suggested above. The shop manual diagrams posted above also show you a test connector on the AFM harness that does the same thing as holding the AFM flapper door open. You bypass the door with a jumper wire on the connector. You should also test fuel pressure with a gauge mated to the cold start injector supply line, not by opening the fuel filter and setting your junk on fire.
Good luck. Dentman

[Duy-]

So it's a stock Bluetop now and not a gze? Why not just buy an engine harness or body harness to replace it with? Also am I the only one who just squirts fuel into the intake manually through the pcv hose to check if it's a fuel problem? Squirt enough and it'll start.

I'm not trying to be rude I'm just trying to say that your labour is worth money too, getting a new used harness would save you a lot of hassle and stress