View Full Version : Engine swap from Hell?

January 26th, 2008, 09:49 PM
I recently purchased my 89 turbo that has (according to the kid I got it from) an engine that was rebuilt (many parts appear new so I believe him) and swapped from a 91. The problem is that it appears to have been done my a kindergarten class while they were on acid. I have counted at least 8 different connector that are not hooked up, numerous vacuum lines that don't exist, gobs of electical tape, and even a few peices of speaker wire. I am having some issues with poor idle and I figure I should sort out all of the wiring and crap first. My main question is what differences are there between the wiring harness of an 89 and a 91 7m-gte and what would be the best way to start sorting out the rat's nest?

Thanks in advance for any help out there.

January 26th, 2008, 09:53 PM
getting the correct harness may help with the wiring issues.
and give the kids a time out with no cookies

January 26th, 2008, 10:22 PM
Are there any resources out there that can help me determine which wiring harnes is currently in the car and which one would be optimal for my application?

January 26th, 2008, 10:29 PM
Do you know if it's an early model or late model '89? If it's an early model, the wiring harness is more similar to an '87/'88. If it's a late model, then it's more similar to a '90. Look for the production date on the data tag in the driver's door jamb.

January 26th, 2008, 11:45 PM
Welcome to Previous Owner hell. POs are whined about often here which is ironic considering many of those doing the whining are future POs who will obviously be just as guilty. Here's hoping you won't be one.

I suggest you first correct everything that has to do with the EFI system then go from there. Either buy a TRSM and TEWD or use the ones online. Check for codes too.

January 27th, 2008, 03:13 AM

Free Online Manual.

January 27th, 2008, 04:02 AM

January 27th, 2008, 06:00 AM
I have a complete 89 turbo harness, ignitor, and ECU. PM me, I wouldnt bother trying to fix a hack job like that.

January 27th, 2008, 06:24 AM
More info and pics of the connectors and vac lines in question would be very helpful.

January 27th, 2008, 07:42 AM
check the ecu in the glove box, if the plugs are yellow its the pre89 harness, if the plugs are grey its a 89+ harness.

January 27th, 2008, 11:01 AM
He means behind the glove box of course! :icon_surp

January 27th, 2008, 11:19 AM
^ Tech..... it's above. :sarcasm:

January 27th, 2008, 12:13 PM
Wow, thanks for all the replies. I will take some pictures now and post them. I have checked the codes and the only one I got was a stored o2 sensor code that did not re-code after being cleared. The engine seems to have a miss at idle, but runs great while driving which is the most confusing part to me. I haven't really hammered on it much just because it's not running properly, but it seems to boost ok as well. Thanks for the help!

January 27th, 2008, 12:57 PM
Here are some pictures of what I am working with. The interesting part of all this is that for each connector that is orphaned it doesn't seem to have anything to plug into. The ecu has grey connectors so it must me an 89+ setup. Thanks again for all the help guys!

Teh Pictures!!!














January 27th, 2008, 01:34 PM
I'd love to reply w/ help, but work doesn't allow Photobucket.

My guess is that it's gonna end up being a test plug for something, or the speed sensitivity thing for the PS rack. :icon_bigg

If it runs, Who cares?

January 27th, 2008, 01:53 PM
1) Ugh. Missing: fan shroud, TEMS, cruise control, EVAP cannister and EVAP BVSW.

2) The red one: VSV for the fuel pressure up system. It'll look like the one on the EGR VSV next to it. The EGR is plumbed incorrectly. It should run through the VSV shown. The way it is now will give enable EGR at all times. Not good.

3) The big grey one might be the cold start injector. It's above your thumb. The little grey one can either be ignored or is the rear ABS speed sensor in the transmisson.

4) See number 3.

5) The white one is TEMs. It's been removed on that car. The blue one is for cruise control stuff, also removed.

6) Got me there. Might be for the AC system pressure switches. They're on the hard lines that run along the fender near there.

7) Other than the crappy connections looks OK .

8) Busted wire goes to the VSV for the heater valve.

9) Nice. That's your ECU

10) You can ignore that one.

11) Look like the coolant loop (larger hose nipple) through the ISCV and TB has been deleted. Not really important.The little hose nipple is for the EVAP cannister. Emissions stuff. Your engine bay pic shows it's missing along with the vacuum valve for it. That normally connects to the front ported vacuum nipple on the TB, the little one just mentioned. The hose that's on the front nipple now belongs on the rear ported nipple for the EGR.

12) See number 2.

13) See number 6 ;)

Might have one or two wrong but hope that helps...

January 27th, 2008, 02:30 PM
Thanks alot for your help. It looks like I've got alot of work ahead of me. Of the things that are missing and or not plugged in, do you think that any of them would be causing my runability issue? It sounds like my egr system may be to blame. I am thinking of just eliminating it since I don't have emissions in my area. Are there any advantages to keeping it on the 7m?

January 27th, 2008, 03:33 PM
I think it has been touched somewhere on SM but, i know that our ecu's are tuned with the egr system in mind.....i think?....i know the jdm 7m ecu's are not from what i understand. Since japan doesnt run emissions they dont instay the data into the ecus. Maybe jetjock can chime in a say if thats right or not. I kept my EGR system though.

need new tires
January 27th, 2008, 03:50 PM
A: the harness you have is for a auto. that doesnt matter, it just has extra plugs that you wont use.i am assuming your profile is correct and you have a r154.

the swap itself doesnt look to bad. minus the fact he used an crappy harness. what i would do is just re-run all the vaccum lines that might help alot. one that is forgoten alot is the power steering vaccum line.

January 27th, 2008, 03:58 PM
EGR could cause a problem because the way it is now the ECU can't shut it off above 4000 rpm or when the engine is cold. As for keeping it my position is well known: it helps surpass detonation and provide other benefits associated with lower combustion temps.

Plus you may end up selling the car to someone who has enhanced emissions. That'll force them to spend a chunk of money if you've tossed the stuff. Remember what I said about previous owners? Then there's the issue of crapping up the air...

All that said if you do decide to lose it run the next higher octane to be on the safe side.

January 27th, 2008, 08:34 PM
That white plug near the ECU, I believe is for the air bag system in the 91. Your 89 does not have it.

need new tires
January 27th, 2008, 09:54 PM
^ the white plug is for the skid control computer

January 28th, 2008, 08:22 AM
that looks like the engine and harness i sold.... O.o hah just kidding.

i can sell ya a charcoal canister + cruise control + tems if ya want. combo deal just pm me :P old stuff from my 7m setup. also have a fan shroud thats about 8 months old... was run for 2 months