JLee's 1991 Toyota MR2 Turbo build thread - part 2

[jlee]

Here we go!

 

[jlee]

The head is at the machine shop - hopefully it'll be done Friday.

 

[dave_the_nerd]

I noticed something rather terrifying at this stage. Exhibit A:

Exhibit B:

I'm not an expert, but am I correct in thinking that the donut-looking doodads that look like they're two half donuts, should look like a single whole donut?

 

[jlee]

I'm not an expert, but am I correct in thinking that the donut-looking doodads that look like they're two half donuts, should look like a single whole donut?

Your assessment is in fact correct. The donut should be whole.

 

[JCH13]

Your assessment is in fact correct. The donut should be whole.

As opposed to donut holes.

Yum....

 

[jlee]

Stuff and things...

 

[Squisher]

I think your head is upside down.

 

[FuzzyDunlop]

V16 lol.
I love the look of a freshly cleaned head...

 

[JCH13]

JLee had some trying times after the head went back on. First there were some issues with ignition system that we sorted out. Then the timing belt broke (on an interference engine!) Luckily everything tested out fine, with 2-3% leak-down on all cylinders except for #3 which had 10% around the rings. After a new timing belt and tensioner, and some prep, I took it auto-crossing yesterday.

It drives pretty okay now!

 

[XavierMace]

It lives!

 

[FuzzyDunlop]

accidentally locked the brakes at the very end there?

 

[JCH13]

accidentally locked the brakes at the very end there?

No, the brakes are just getting really tired on the car, the pads are almost gone! It didn't slow down as quickly as I needed it to. I didn't wind up locking them because the tires were so damn hot and sticky!

 

[jlee]

The day before the annual Bear Mountain MR2 meet, the car died on me in a parking lot. Troubleshot it for a couple of hours and determined it's likely igniter failure. Towed home, got another igniter from someone at Bear Mountain and swapped it out - no dice. It was quite corroded, though, so I tried another one today (also ordered on eBay previously). I learned exactly how the ignition system works and went through this process:

Coil:
1) Positive - has voltage
2) Negative - 1.2 ohms to igniter harness

Igniter:
1 White/Red to ECU plug B 3rd spot (IBF) - not used by the ECU Masters EMU
2 White/White to ECU plug B 20th spot (IGT) - receiving voltage while cranking
3 Black/Red to Ignition Main Relay (12+) - verified 12v with key on
4 Black/Black to Tachometer - irrelevant for spark
5 Black/White to Ignition coil - 1.2 ohms to coil harness

I put the new igniter in and it fired right up.

 

[jlee]

Updated the to do list. Still nowhere near done, but it's getting dramatically shorter!

 

[jlee]

Well, it died again. Same symptoms as before - replaced the igniter again with used OEM part, no change. Bought a brand new coil, no change. Bought a brand new igniter, no change. Verified 12v at the igniter, verified 12v at the coil, verified continuity between ECU and igniter, and even changed the ECU to send ignition signal out another output (in case ignition #1 driver was bad).

Still won't run.

I have an oscilloscope on the way to help narrow it down. On the bright side, I moved as of Jan 1 and now have a heated garage.

 

[jlee]

I just realized that, for the cost of the new igniter/coil that I bought to try to fix this, I could change over to coil on plug and eliminate the entire OEM mystery-box ignition setup and go to something directly driven by the ECU (3 wires per coil - common power, common ground, unique ignition driver). Clean and simple.

So, I have a new project.

 

[jlee]

all the things are here.

 

[XavierMace]

Hopefully this solves the mystery problems.

I will go knock on every piece of wood on our new gate for you.

 

[jlee]

Hopefully this solves the mystery problems.

I will go knock on every piece of wood on our new gate for you.

We all have our dreams, lol.

 

[jlee]

woot

 

[jlee]

Took it out for a spin and discovered that the speedometer doesn't work...but on the bright side, I have a clean (and warm) place to work now!

 

[jlee]

Broken speedometer sender key. Ordered a new one..hopefully they're still in stock from this place, as I hear Toyota ran out of them.

 

[jlee]

The key replacement fixed the speedo, btw.

I've decided to put the MR2 up for sale - with my reduction in garage/shop space, I don't really want to commit the time to finish the little stuff. I'll have to content myself with the new toy:

 

[Fenixgoon]

oh the huge manatee congrats!

 

[dave_the_nerd]

I feel like we're losing a family member.