Car cranks but won't fire - SOLVED

[Sawbladz]

Did the basic continuity test and it seemed to check out fine. I was having trouble figuring out which pins were which. The label on the relay is not very clear and the TSRM picture doesn't realy help either.

EDIT: Fresh eyes and a bigger screen helped. Checked the basic continuity test and it passed. Now making jumper wires to test it with 12V

---------- Post added at 12:34 PM ---------- Previous post was at 12:33 PM ----------

I'm getting ready to pull the glove box all apart again and go over all the connections made for the ECU and the MAFT-Pro. I'm not liking where this is going.

 

[Sawbladz]

Ok, the main relay in the fuse box is functioning correctly. This is about all the time I have for this problem today unless I take a break from studying later. It seems like the problem is likely to be with the ECU or its wiring so I am thinking it's time to pull all the wiring out from the firewall and check it. That has to happen anyways to wire the boost controlled so it won't be a waste. Is there anything else I should check before I take that step?

 

[CajunKenny]

Did this happen on it's own or did you change/install something and then this problem surfaced?

 

[Sawbladz]

Have a look at my build thread. Everything changed. The car has not yet started since the car went back together. This is why I started by retracing my steps on the coil wiring. There might be an issue with the wiring done to the harness for the MAFT-Pro. I didn't do that personally. It was already done by the person I bought this drivetrain from. Guess its time to recheck his work and my own.

 

[CajunKenny]

I see... What a bummer.

Well, I would start by chasing power.

 

[Sawbladz]

Yup. Heres hoping it's something stupid. I'd love to find a plug not hooked up...

 

[Sawbladz]

Ok, wiring harness is back out of the car. Before I continue I want to state that this wiring harness is not mine. It came directly from a car that was hooked up and running a MAFT-Pro. I scanned the piece of paper I used in comparing my wiring harness connections to the ones found in this thread.

http://www.supramania.com/forums/sh...tall-writeup&highlight=MAFT+Pro+install+guide

Apparently, instead of using the +B1 pin for power, he used the +B pin. I want to know what effect this would have and whether it could be the source of my issues. I am very confused at this point because his car ran and ran well with these connections. All of the other connections seem to be correct.

Here is my scanned work. I have not noticed any other problems with the wiring so I think this is a good place to start.

 

[SRZMK3]

there is a fusible link wire that is pretty decent is size that comes off the battery and into the fusebox area. those tend to break, thats what happened to mine. find it and rewire it.

 

[Sawbladz]

When you fixed it, did you replace it with the appropriate fusible link or just a large gauge wire? Do you know what the rating of the fusible link was? Is it possible to replace a fusible link with an inline blade type fuse?

 

[Sawbladz]

IT RUNS!!!!!!!!!!!!!!!!!!!!!!

I want to thank everybody for their help in diagnosing this. JetJock, you were right. It was the main relay but the reason it wasn't closing is that a wire was cut on the harness. Fixed that and it started right up. I did not change the pink power wire for the MAFT-Pro because I wanted to change one thing at a time to see what the problem was.

 

[CajunKenny]

That's awesome! Glad to hear you found it!:thumbup:

 

[jetjock]

Persistence pays off. Sorry I wasn't more help (there are many things that can keep the main relay from closing) but I'm glad you found it. Like Kenny I would have left the harness in the car and troubleshot that circuit with power applied but whatever works for you is all that matters...

 

[Sawbladz]

Persistence pays off. Sorry I wasn't more help (there are many things that can keep the main relay from closing) but I'm glad you found it. Like Kenny I would have left the harness in the car and troubleshot that circuit with power applied but whatever works for you is all that matters...

I just had a serious distrust for this harness. I wanted another look at how those connections were made.