vigman

I asked the following questions to a Speed shop… and the tech really knew his stuff..

In my son't car this is what we have:
Harness TOY 82121-14880 Fed harness, for 93.5 - jan '96. (OBDI).
Supra ECU - 89661-14520 (93.5-95) Part Numbers (6-speed, US Spec, TT):

So I thought I would share these nuggets….

Questions:
1) A buddy has a KNOWN GOOD ECU out of his ride.. but the car WAS an automatic Will this " function" just for a test fire to prove a bad ECU ?
2) Is there a company that " Tests " ECU's with some form of car emulator?
3) Is an ECU's personality contained in the 2 "EPROM's" in the ECU?

1-- Yes to prove power / ground / MREL circuit am auto ECU will work. Depending on how start/ neutral safety is wired/ bypassed it will probably not start or even crank.

2-- To the best of my knowledge, NO there is not a company that tests ECUs with an emulator. I can with with a 2J MoTeC jumper harness and $12,000 MoTeC engine emulator check the stock ECU pin by pin. Or Aaron at DriftMotion can check the ECU outputs on a bench as easy as I can.

3-- Yes the Prom contains the specifics and cal info of the vehicle. Other than that the boards are different because of the different outputs. For ex. Auto cars have 5 more PWM drivers for the solenoids in the transmission than a 6-speed manual. Etc.

So the punch line was :
We were missing the ground pin 4 of the 80 pin... it's not on the factory harness...
So we had extra pins and LO and behold we got a check engine light with error codes 21 & 27 ( O2's not working ) which was correct ... since I do not have these currently connected.

ODB-1 codes can be found here:
http://mkiv.com/techarticles/engine_...bd1_codes.html

gerrb

iTrader: (34)

Mike - I am no way near being a professional with automotive compared to the professional you talked to since both my BS and MS degrees are in Computer Science... totally different line of discipline . Am just a mere enthusiast of these cars but I will beg to dis-agree with the statements that was said above that I highlighted purely based on experience.

Did you by the way use the OEM Toyota head gasket or an after market one ?

Reason I ask is, OEM Toyota head gasket can ONLY be installed one way. The block has a dowel on two opposite sides diagonally. It won't let you install the head gasket UP SIDE DOWN . But , you can install it wrongly by putting the front part of the gasket at the back and the gasket holes for the dowels still line up so it will go in. BUT you would notice it since two of the opposite holes diagonally located will not line up and part of the gasket will protrude out of the block.

I can take some pictures if you want since I have other blocks and an old head gasket here.

gerrb

iTrader: (34)

Mike - looking at the picture of the gasket on your block on post #7 , to me.. it is installed right .......

Here is your picture

vigman

I do not remember since it was " provided "… it's a copper 2 layer riveted gasket which has 5 ? symbols stamped in it.. I will put further info up later.. I'm passing this info on , the guy " seems " VERY VERY VERY knowledgeable.
( but hey I'm a noob ) … so I remember we did spend some time inspecting it closely, and me being OL SKOOL was looking for TOP or UP…. PPFFTTTHHHH.. We are still on hold due to David's school schedule… but if we find the tab ( which I couldn't see from the top yesterday ) so me thinks I have to go under and take a peek…just to CONFIRM this possible data point~ The more info ( to a point ) better choices can be made~

Thanks Gerrb I really appreciate the input!!!

Mike

vigman

That was from the initial prep of the engine.. but WE had to pull the head due to no compression, due to improperly tipped valves...

gerrb

iTrader: (34)

Using your head gasket as our point of referrence why an OEM /. Toyota head gasket cannot be installed upside down



* There are two dowels on each side diagonally located.. in Red

* If you invert the gasket up side down..it won't go in because
a) the hole in yellow on the head gasket is smaller compared to any of the other two corner holes on the gasket with a dowel. It was a precaution so as not to be able to install the head gasket up side down.
b) if you invert the gasket.. one of the holes with dowel won't line up... hole is halfway covered only

* let's say you just accidentally put the back part of the gasket in front , then you will notice holes in blue not lining up. Look at upper right corner and lower left corner of gasket... one has two holes and the lower left has one.. so it is so evident it is not rightly installed cause a part of it will protude out of the block and the hole you will see does not match the block.


Here is a picture of my OEM Toyota head gasket on my Red Mamba Two... same orientation as yours. The numbers you are saying are near the 6th cylinder facing up on a extended metal piece on the gasket ( Right top of the picture below)

vigman

This is the OLD gasket that came out …. the new one looked identical.
I do not remember any toyota markings on the box…
BUT I see what you are saying, the gasket is ALMOST idiot proof…
Since the OD on the front & rear holes are different.
I remember it laying down nice and no forcing in corners..
We will still deep dive to confirm
But then again it took us a WEEK of figure out the pass side motor mount.

vigman

What I cannot find is a Toyota cross ref to the JMG 372 number….

I would ASSUME any after market gasket would model the factory gasket..

Rut ROOOOO there is that ASSUME… AGAIN

SO this leaves us back to the Oil cooler on the side of the block .


Thanks
Mike

gerrb

iTrader: (34)

that JMG???? is probably a production number..I have them in 3 old toyota gasket I have laying around. The numbers differ. The Toyot part number of the gasket is 11115-46052. I have two new aftermarket gaskets here and do not have those JMG??? numbers. So more likely Toyota gasket is what you have.

Did you inspect the head for hair line cracks ? So even after changing oil.. again you started getting same vanilla like oil on the engine ?

EDIT.. YES.. the aftermarket gaskets with me have exactly same hole sizes ... so still they cannot be installed up side down.

vigman

That head JUST came from the machine shop.. I ASSUME they did all the inspection.. but then again I ASSUMED the would do the job RIGHT THE FIRST TIME!

CatManD3W

iTrader: (18)

Here is another view of the OEM TT headgasket....just make sure all holes line up exactly ...I had to look at some other engines being built to double check I was installing it right...






When facing the front of the engine i.e piston #1.....on the left rear should be the tab sticking out from head and block...

vigman

Cat man... Thanks for the input....
SO the only way we can check the work without pulling every thing apart... again
Is to inspect that tang on the gasket.. and it seems the only way to see it will be from below.

vigman

Well *****…
Got the Harbor freight cooling system to work ( My son cheated & read the directions )

We could only get the system up to 9 psi… it leaked down in under 2 min.
He heard GURGLING in the sump
Bypassed the Oil cooler… same dealio
So looking for advise on is it possible to flip external lines so OIL and COOLANT interchange?
We are both REALLY frustrated and walking away from it for today so we may fight another day.

Oh and … David crawled under the car and can see the block / head junction on the pass side by #6 but cannot see the tab with the number.. I will look later today as well.

GAH~

gerrb

iTrader: (34)

^^ What do you mean ?

when you bypassed stock oil cooler and connected a coolant hose from the block directly to the wrap around pipe , do you still have oil mixing with coolant ? If yes, you know , that the problem will be inside the block.. either gasket or crack somewhere

vigman

Gerrb.. We didn't re fire the engine. ( today ) .

We ran a separate hose bypassing the cooler sandwich..
What we got was a fast leak down and gurgles in the pan. Same as before so nothing has changed.


Current state is no coolant in radiator, fresh load of oil in engine .. and run for 30 seconds. ( yesterday ).


We have not located the gasket tab.. so we are NOT 105% sure that is correct.
It's almost like an oil & coolant line ( or passage ) are cross connected...Or in a worse case a crack

But that amount of coolant/ oil exchange in under 2 minutes.. Godzill could fit through that….

Just FYI it's a JDM bottom & turbos with a USDM head, intake injectors on top…. ( if that matters ).
Tomorrow more deep diving to find that " tang"