vnova94

Im pulling my engine, and im having a hell of a time unplugging the engine harness...... The last two connectors are the two plugs that connect to the ECU, but what the heck are those other three connectors? I can barely get my hands up behind the dash to remove anything and started pulling everything, but it's still not budging.

Any suggestions on getting this thing through the firewall?


Thanks,

Matt

RXTASY1

Why are you trying to take out your engine harness?
I usually just pull the intake off and lay it to the side.
It makes it easier when you put the new engine back in.
BTW.... If this is your first time, mark EVERY connection so you don't get them mixed up.

kliftin

yo rxtasy. What if you did want to take out your wiring harness. How long do you think it takes. I need to do it on mine. I think the whole manifold needs to come off or something. can you telll me how. I need to put my new harness in.

RXTASY1

I have never pulled the whole harness out, but it looks pretty easy.
The hardest part is getting it out from under the vaccum spider under the intake.
Yes, you have to take your intake off regardless.
After that, you will just have to work through the boot on the firewall and unclip it from your ecu. Or if you dont need it anymore just cut it!

Thaniel

I put a new wiring harness on in one evening. Took maybe 4 hours? Wasn't counting. Had to unbolt the top half of the manifold from the bottom half, loosen some other brackets and raise it up about 2 inches to get underneath the manifold to the injectors and a sensor on the top of the engine (the last 3 plugs to hook up if you start at the ECU first).

The dealer wanted $2,000 to do it. Cost me about $500.

kliftin

yo thaniel. what exactly was the 500 for. the labor was free right. I have my wiring harness already. please reply.

HAILERS

I've pulled one from the junk yard before. One of those connectors is to the atmospheric pressure sensor. The others are just what I call disconnect plugs from one harness to another. Just punch out the big rubber grommet at the firewall. If you have a turbo there is also a plug for the knock sensor. Its not really that hard the second time. Just gonna scratch up your hands a lot getting the plugs disconnected. I believe your putting in a new harness because of some electrical problems you had. Right? Like burnt wires, popped fuses etc. The harness will feed out that grommet hole doing one plug at a time.

kliftin

thnx, I apreciate it. Meckanic estimated 600 in labor and it averages 4hours. thats amazing.

kliftin

HEY EVERYONE. TELLL ME THIS. IF MY STEREO WAS THE ONE THAT CAUSED MY SHORT. IS IT POSSIBLE FOR IT TO STILL WORK. I CAN LISTEN TO TUNES ALL DAY WITH THE KEY IN.

Thaniel

$500 was for the harness. Should replace the intake manifold gasket at the time too.

jeff88

LOL

Looks like i'm in the same boat. I'll probably end up deplacing my harness as i've got an electrical problem too. I thought that I had the problem wires isolated and repaired, but I still am not getting any spark, getting fuel though.

Will the harness off an 86NA work on an 88NA?

Thanks fellas.

How's it going kliftin?

Are both of the wires that go to and from the ecu fuse burned? Mine are, so I spliced good wire between the bad spots and it still doesn't get spark. I just don't understand it! F%#*ER!

kliftin

OK, first I bought my harness from a junk yard for 150. second I heard that 86-88 will work as well as 89-91 for mine. I have an 90 plug for my 89. Im just peachy. just towed my car out of the shop today and am stoked. spent alll day cleaning it. As for your question. I think we have to different probs because my wires burnt underneath the hood but stopped before they reached the egi. Im going to start taking off the manifold today. Hey why dont you pull some trouble codes out of your car. It might tell you whats not working and that might be grounding your spark or something. Anyways got to work on it and like I said, my dam radio still works. so that means its not shorted right. I mean how can it be shorted If it still works. Ok. got to go. good luck.

rx7_ragtop

The 86-88 harnesses are ALMOST the same- 86 and early 87 use low-impedence injectors on the TII, not sure on the NA. They have a "block" of resistors tied in to the injectors, you have to use the correct injectors for the harness. Series IV (86-88) and Series V (89-91) harnesses are NOT interchangeable.

Brad

jeff88

Kliftin-

Glad to hear it's going ok. My wires burnt in the engine bay too. One snakes over the alternator(in a bundle with many other wires) down then splits one bundle going to the fire wall the other to toward the airbox. One of my bad wires was burnt around the alternator and down, but didn't make it even close to the ecu. I might just get it diagnosed by my mechanic and then fix it myself. I need to take the manifold off to free up my 5th and 6th ports. One opens partially and the other not at all. Just didn't want to crack it open. Now I may have an excuse. I'm not sure how to check the error codes. I'll look into it though. Thanks man. Let me know how it goes and i'll do the same.

kliftin

ok, I forgot where I saw that trouble code thing posted. I will try and find it again. I pulled off the intake today. It was a sinch. Going for the manifold tomarow. I noticed something crazy. On the intake at the end of the runners thiers the gasket wich seemed to be blocking a lot of flow on one of the runners. I wonder if I can grind the gasket. you think so. Also the runners are rough as hell. I wonder if I can polish it myself with a dremal. Cool.

Thaniel

I don't know about using a harnes from the junk yard. The one on my car was getting hard and nasty from all the heat from the engine.

Jeff, My car went belly up due to the harness. Sounds similar to yours. I had no spark. Previous to it not starting it had ocasionally studdered like I had switched the key on and off.

Dealer spent all day with the stupid thing trying to figure it out. Tried a different crank angle sensor, ECU etc. Actually found that moving the wires going to the secondary injectors would get it to start. Once running I could wiggle every stupid wire and the thing would not stop. That is until I started driving. 5-10 miles down the road it'd quit.

I tried replacing sections of the harness but it still kept quiting. There were so many bad spots I finnally put a new one on it. It's been over a year now and it hasn't missed a beat since.

jeff88

I'm going to go after mine this weekend if I can get gaskets by then. I don't see why cutting out the extra gasket would be a problem. I was thinking about doing a little porting or polishing too. Can't hurt I think. From what i've read here it looks like very little power gain, unless you get a glass bead port job.



Thanks for the info Thaniel.

kliftin

I just tore off both intake runners. I found out that I didnt have to take the manifold off. The secondaries were right next to it and the harness connector to it snaped right off. Phewww. It took around 4 hours. Now I can probly do it again in 2. The biggest problem is trying to fit everything like the wires were they went origanally. I video taped some stuff but need to go to a junk yard today to buy a couple of small vacum hoses and see exactly how the wiring harness lays. I hope I put everything back right. I will probly try and start it tomarow. And if you have your intake off or are going to. why not port and polish it. I think more gains than you think will come out of it basically because they felt so freakin roughf it sucked. Why didnt they come polished from the factory. All well. I didnt do mine because of the time. Anyways I had fun but got sunburt. Talk to ya tomarow.

kliftin

does anyone know what those two wires coming out of the acv are. One is black w white stripe and the other is blue with white stripe.

Thaniel

There should be two sets of wires comming from the ACV (at least there is on mine). One is for the split air solenoid and one is for the port air solenoid. Only for Emissions. Doubt either would make a bit of difference on how it ran.

kliftin

HEy im back . PUt everything back together today. Tried to start it but need a couple of other wires hooked up. Going to try it out today.

kliftin

j

jeff88

AARRRRRGGGHHHH

Just went and looked at the wiring harness out of my parts rex and the jackass who took out the engine just cut the harness. DAMNIT!

I'm going to try to get it working without changing the harness. Going to buy a good tester and test everything for power and then go from there. What a pain in the ***!

kliftin

ya , that sucks. People do that in junk yards to. Anyways how do you check the wires. Put the tester light on them and makes sure it lights up or something.

kliftin

oh ya. Me and my friend and some girl was working on it all night. Had a little flash light. Thiers three connectory that I dont know where they go. Have to look at another 7 today. Also I tried starting it anyways. Car light turn on but everything just clicked off When I cranked it. They turned back on after moving the batt. Must tighten. Then for some wierd reason the dash light and everything else went out so I replaced the fuse and went on again. Blew the fuse again so replaced it with a smaller amp fuse now it hasent blown. Crazzzzzzy **** man. This car is f.......u........c.......k.........e..........d. Will let you know what happens.