Supra no go.

[Setheroo]

My old thread has shown its age, and it will no longer let me reply to it. But let me sum it up in a few short words... I put the 89+ engine into an 88 model, and it is giving me loads of trouble.

I really thought my problem was the injector wiring and everything along those lines, but even though I have now solved all of that, I still have... a lot of problems.

Where to begin?
Lets see...

• I installed an 89+ ECU and harness with all of the 89+ injectors
• Everything in the engine bay wires up perfectly, but underneath the glove box the body harness will not plug up with engine harness
• I sorted through a lot of the wire colors and pin counts on the connectors, and they do not match up
• I started to manually hardwire what I could, and did enough to get the engine to crank
• Engine will crank all day long but the fuel pump needs to be manually turned on..
• I am getting spark, and fuel, and during cranking it will spit and sputter..
• Once I stop cranking it lets out a hellacious backfire
• I triple checked my timing and firing order and its all correct...
• Since I was so close to getting it running, I towed it to the Toyota dealership to have it finished... and they called me today saying that it would never work due to the year differences....

I REALLY do not want to sit here and believe that there is no way for my engine to run just because it is sitting in an older chassis... I am sorry I don't buy it.

What can be done to hook up the newer harness in with the older harness?

Any input is appreciated... I have been working on this car for over a year now!

 

[cruisnhard]

I had a similar issue and it even blew off the intake pipe. It was my timing 180 degrees out. I pleayed with the distributer and got it to turn over. Then it started. The only difference is that my body harness plugs up to the ecu. Just to make sure you have the wiring correct into the body harness for the pump.

 

[Setheroo]

I had a similar issue and it even blew off the intake pipe. It was my timing 180 degrees out. I pleayed with the distributer and got it to turn over. Then it started. The only difference is that my body harness plugs up to the ecu. Just to make sure you have the wiring correct into the body harness for the pump.

Was your timing out only on the distributor, or was it out on the camshaft and crankshaft timing? You can have a timing belt pulley out 180 degrees.. which is what I ought to start checking into next..

I can here my flapper in the MAF rattle back and forth during long cranking... is that any sort of sign...? I have had Celica MAF's go nutso before and they still ran fine... so I am not sure what to think or do next.

 

[Ma70.Ent]

My old thread has shown its age, and it will no longer let me reply to it.

You can reply to it. You just have to read a little bit

 

[supramacist]

Pull the codes.

 

[SupraSabre]

Maybe re-wire the body harness with an 89?

 

[Supraflymk3]

yeah you should of stuck with an 87 or 88 engine. or else bought an 89+ body wiring harness because 3 or 4 plugs are different from the 87 - 89 plugs and pull out your 87-88 harness.

 

[Setheroo]

I don't think that pulling the codes would do me much good, it is possible that it could even steer me in the wrong direction considering that my harness isn't fully wired up.

Swapping out the body harness would be a real PITA... I am seriously thinking to myself that it would be easier for me to swap out the engines again rather than rewire my whole chassis.

I have found a 87 NA with a MT... full engine harness and ECU in tact.. and I think I may just go that route... since I have torn my car apart and put it back together so many times it should be a breeze.

But before I go through with doing all of that... I would really love to hear the engine I have in there now run... so if anyone knows of a way that it could work... or has a good idea of what exactly is stopping me from having my engine running... the input would be much appreciated.

Thank you all.

 

[cruisnhard]

it was my distributor. Once it was fixed it started right up. the flapper in my maf was going crazy also.

 

[f00g00]

I would have thought the 89+would work fine in the older chassis if you just use the old injectors and fuel rail and throttle body from the older engine then you could keep the original harness and ECU. Ive had newer engines put in mine and they allways just had to swap out the old fuel rail,injectors etc. The engines themselves should be the same, head and blocks with maybe minor differences with sensors.
Swapping out body harness would be a real pita that I wouldn't attempt.
The reason they changed the throttle body is because the engine I put in had a setup with two TPS's and Im thinking wth is that thing with two?

 

[Supraflymk3]

yeah that 89+ engine should work perfectly fine in there as well. i would leave it in and get a new 87,88 ecu and wiring harness and put the old injectors in, even though I think they were all low impedence on N/A's but maybe different plugs.

 

[supramacist]

You either need an old engine or a new harness or you have some hard wiring to do. So you may as well meter everything.

 

[Setheroo]

I have found that the VSV plugs don't match up, nor do the coolant temperature sensors, the resistor block wiring isn't on the new one... needless to say, the harnesses are not near being the same... it would take quite a bit for me to get it going the way it is now... the older harness that I have is all sorts of screwed up from splicing into it so many times...

I want to just go the route of putting in the right year engine and harness with adding in the 5 speed... I prefer the five speed much more anyways...

Gollee this project has taken me way too long.

All for an NA too... wow, never again will I go through all of this.. for something that MIGHT put out 200 hp.

 

[mikesupra87]

wow im having almost the same exact issue...cept Im puttin a 89+ motor in my 86.5 Supra. Its got great spark, and fuel is gettin to the injectors but the injectors arent firing. How did you figure out the injector problem?

 

[Setheroo]

You need the low impedance injectors from the other engine... the ones on your newer engine are rated at like 14 ohms while the ones on the older models are 1-3 ohms...

 

[polobai]

Your simple solution is to swap the 89+ harness for the pre 89 engine harness and computer. The motor itself will not cause any problems, its the electronics. You will probably have to swap the injectors again-but I am pretty sure the old harness will get your running again.

 

[Setheroo]

I have found myself in a mess to get my car going yet again.. but here is how it all goes.

• Bought an 87 NA with W58
• Bought the clutch pedal and brake pedal assemblies
• My car was an automatic, I already ripped the engine and transmission out
• I have a new NA 5 speed harness, already wired to the engine
• I have the NA 5 speed ECU ready to go

Now my questions is this: since I have the manual ECU... will jumping the neutral safety switch even be necessary?

I have no clue as to where the connector would be at for my clutch safety switch, and I know that for the starter to engage it will probably need to see reference from the clutch switch.

So how do I get around all of this stuff?

Does my body harness have hidden away a switch for the clutch that I just dont know about yet?

I just need to figure all of this stuff out soon, it has been over a year since my car has moved, and it really needs to be running for me to drive home for Christmas...

Thanks

 

[Setheroo]

During my pedal installation... a green light fell down out of its socket... and I have NO idea as to where it fell from... anyone know where it plugs up to? I know that my ignition switch has green illumination from it.. I am thinking that it might be that.

Anyone ever have this light drop down from underneath the dash before, or does anyone know exactly where it goes?

 

[mclabaugh]

the green light is just a courtesy light that lights up the driver foot area when the doors are open, its right by the hood pull handle.
the nuetral safety switch will be right at the top of the clutch petal where it meets the firewall on the inside of the firewall. i've just cut them on other standards and never had to push the clutch in to start it.

 

[Setheroo]

the green light is just a courtesy light that lights up the driver foot area when the doors are open, its right by the hood pull handle.
the nuetral safety switch will be right at the top of the clutch petal where it meets the firewall on the inside of the firewall. i've just cut them on other standards and never had to push the clutch in to start it.

But will it still be there even though my car was an automatic? That and what color will the connector be?