Startup Issues with new motor

[TheEngineer]

Well i posted this on mr2oc but i havnt really been able to get good help.

Ok we have a strange problem and I think we have a grasp on what it is doing we just have no idea exactly why its doing it.

First here is some relavent info:
- AEM EMS
- Built Motor
- Precision 680cc injectors
- AEM IAT/MAP sensors
- Walbro 255 Pump
- GSC S1 Cams
- Fidanza Cam Gears

And now the issue. When we get it started it wants to stall which we have now traced to the fact that its running on only 2 firing cylinders. The exhaust is dumping fuel out like crazy. So we remove the spark plugs and low and behold Cyl#1 & 3 are totally clean as if they never fired and Cyl#2 & 4 are black as they should be. So we now know why its dumping fuel out the exhaust. Here is a list of the things we have checked:

- Cam Timing (good)
- Spark to the plugs (good)
- Firing order on the spark plug wires (good)

Now our thought is that Cyl #1 and 3 are firing off 180 Deg. and basically when the plug fires it has already dumped all the fuel out the exhaust. Now we have tried figuring out why it does this but we havent been able to come up with a solution.

Also an afterthought we had but decided to pack it in for the night, was that possibly the cam position sensor on the distributor (the key thing) can be off by 180 deg. But is it possible for that to be off by 180 or can that key go on either way. I know when i looked in the manual it seemed pretty evident that it should be installed only one way. Is this the case?

Thanks for all your help and sorry for the long post.

[TheEngineer]

and i know now that the dizzy only goes one way. But im still not sure thats the issue, so anything you guys can think of may help

[MR2Jedi]

When I 1st cranked up after my rebuild, I was (embarrasingly) 180degrees off on crank-cam alignment! It ran,-amazingly, but not well.
Idunno. Maybe take off timing belt, rotate crank 180 back to 0 and reset cams.
And yeah, distributor shaft can only mate with intake cam one way.
What about the injector electrical connectors? Could they have been cross connected?

[TheEngineer]

no when we did the wiring to the injectors we did them one at a time as to not mess that up. And im pretty sure the timing belt is fine because we did it to the factory service manual specs with the motor out. I would really hate to try and re-time it with the motor in, haha. BTW thanks for the ideas. I will check this stuff just as a double check

[Ghostyman]

I saw the mr2oc thread too... regarding the dizzy, the key itself can be installed on the shaft backwards so it will be 180 degrees out. But the car won't start then. I had this happen when I rebuilt my distributor. To verify that was the problem, I swapped the 1&4 and 2&3 plug wires on the distributor which put the timing back to the proper order (by reversing it 180). Probably not relevant here but throwing it out there.

[TheEngineer]

hmmm, interesting.

But yea its really baffling to me that i have 2 plugs that are totally clean and are getting spark. They should be black. idk, this whole car has just been a PITA from the begining.

oh and thanks for the help, i just read the post on mr2oc

[MR2Jedi]

Originally Posted by TheEngineer

. I would really hate to try and re-time it with the motor in, haha. BTW thanks for the ideas.

I hear ya.. its a PITA.

Originally Posted by Ghostyman

regarding the dizzy, the key itself can be installed on the shaft backwards so it will be 180 degrees out. .

Hmm? This is a possiblity if you dismantled your dizzy.

[toyotaspeed90]

if you are getting spark at the plug and it's a fixed distributor (ie only one way it goes in) and belongs to the ecu you have (and no wiring was crossed between the ecu and the ignitor) then the problem isn't spark.....

have you at least used a stethoscope to hear all injectors firing? How did you wire them? The timing of the injector spray actually isn't as important as you would think..... if that's off even 180* the car will still run with little beknown to you....

[TheEngineer]

Well figured id let you guys know what the problem was. 2 of my brand new injectors were stuck open. Im going to be getting them replaced hopefully at no extra cost.

[MR2Jedi]

Wow, who woulda thought new injectors would be the problem. Glad you worked it out.

[TheEngineer]

yea thats what i thought too. One of my buddies said it in the begining too when we had the problem that maybe the injectors were stuck open. But we kinda ruled it out because we figured what would be the chances that TWO brand new ones would be.

[toyotaspeed90]

$5 stethoscope from harbor freight is a great thing to have.... I have 2.