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Discussion Starter · #1 ·
I have a 89 MX6 GT AWS. I just finished rebuilding my motor completely. And I have done a few mods along the way. I have 90-92 injectors and clips, EGR delete, EVO 8 intercooler with 2.5" piping, A/C delete which I have a pulley now, 2.5" exhaust. And I'm on a stock turbo with the "boost solenoid" taken off.

My problem is.... She turns over and runs for a second and then dies. I got her to rev up to about 4500 rpms 1 time and it didnt happen again. Zach came over and helped me trouble shoot my problem and he was stumped too. We switched ECU's, checked wires, checked spark plugs, tried reading codes but the only code I am getting is the "boost solenoid" delete which is harmless. Just before we gave up we tried spraying started fluid around vacuum tree and it did nothing! we sprayed some in the VAF and she took off for a 3-4 seconds and then struggled again and died! Zach suggests switching the injectors and clips back and leaving it stock. Please help, she is soooo close but yet so far away! :confused:
 

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The injectors might be the answer. Check if your getting power to them, sometimes switching clips messes up the harness.

HAve you guys tried checking the throttle body positioning sensors? I remember my car going putz and not staying on when that happened.
 

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Discussion Starter · #3 ·
I had a extra throttle body so I put that one on too! So I did try and switch them. This next weekend I am going to switch the clips back. My fingers are crossed! The problem is totally starring at me in the face!

I did move my TPS on my old TB thats why I changed it out. Thank you for you reply and input!
 

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Discussion Starter · #4 ·
Also, Zach and I listened for the injectors clicking with the "screwdriver" trick. We heard them clicking... If there is no power they would not click would they?
 

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Also, Zach and I listened for the injectors clicking with the "screwdriver" trick. We heard them clicking... If there is no power they would not click would they?
they wouldn't click if they didn't have power.


random thought from last night, is the knock sensor screwed in fully?
 

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no they wouldnt click. There's a few idle sensors over there in the TB that might cause your car to choke and die.

Also, have you done any mods to your VAF?
 

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Discussion Starter · #7 ·
I put the knock sensor on before I put the motor in. I can check that too! No mods to VAF. That would not be a good idea lol. How would you check the knock sensor for failure?
 

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Discussion Starter · #9 ·
While Zach was trouble shooting he noticed I dont have a vacuum chamber on my vacuum tree. And I replaced my vacuum lines with different vacuum lines. BUT the vacuum lines that were on my car were not factory! they were the after market "blue"... and I did not have a vacuum chamber on my car when it was running previously. Could this pose a problem?
 

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its easy enough to test for. just pull off all the lines where they connect to the manifold and cap them off. run separate lines from the manifold to the fpr and bov. you should only have one line to cap after this is all done, its gonna be pre tb.
 

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Discussion Starter · #11 ·
although this is a test for the knock sensor it will not give a reason as to why the car is not running will it?
 

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Discussion Starter · #12 ·
Zach was also saying that my VAF was reaching surge... Whatever that means?

Also the cylinders are getting plenty of fuel. The smell is strong when removing the spark plugs.
 

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The knock sensor shouldn't cause it to not run.

Do you have an extra disty? I've seen similar problems when a crank position sensor was going out. Not sure if it would act the same in our case though, you would think if there was no CAS it would never spark or inject fuel.

It sounds like its starting with the extra fuel given at start-up, but after the start-up enrichment its running out of fuel. I say this b/c it tried to stay running when spraying the starting fluid in the VAF. On non turbo cars, with much shorter intakes, i've used a spray bottle with gas in it and kept spraying fuel in the at the airflow meter to see if it would keep running. If it does its most likely a fuel issue. You might check fuel pressure, fuel filter ect.

Although it could always be a sensor telling the ecu run way too lean. IE: you have a vented bpv and air is getting sucked in through there rather than the VAF. If enough air got sucked through the bpv, the VAF might not even open at all, which causes the fuel pump to turn off.

Could be tons of things. Don't you just love FI? haha
 

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Discussion Starter · #14 ·
When the disty is moved from one extreme to the other it changes the reaction completely. Far left runs like poo, and far right sounds like it has a chance. The disty could be a very good thing to check. I wouldnt mind picking one up, would it be safe to do salvage yard or brand new. I'm kinda strapped. And also my new ic pipping is in the way so I rigged the TB boot to go on the VAF... If there is air being sucked around the VAF, the VAF will not work properly? I'm also reaching surge in the VAF... so that means it working right?
 

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no idea what zach means by surge. you should be able to unplug the vaf then just remove the tb boot and run like that, just don't rev it too much.

loose knock sensor can cause lots of weird issues, as what happend on my friends dsm. it thinks its knocking all the time and throws timing everywhere.
 

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Discussion Starter · #16 ·
With the VAF on or off, plugged in or not it still doesnt work. I sounds more promising with it on. So I should attempt a new disty and knock sensor. Its not the wiring its not the spark, its not the fuel... It totally sounds like the timing is F'd and just for curiosity I took my BOV out cause it was a cheap one, and made it a closed circuit. So I am not experiencing any air leaks.
 

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Discussion Starter · #18 ·
are you free this saturday? I would LOVE the help. I am SOL on a BOV but she is ready to run. I am really frustrated with her. I can work around your schedule too if possible. I would love for you to look at her!!!!!!!!
 

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loose knock sensor can cause lots of weird issues, as what happend on my friends dsm. it thinks its knocking all the time and throws timing everywhere.
I drove around for two months with the Ks code and it never really gave me any trouble. But I guess its still a possibility.
 

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Discussion Starter · #20 ·
Zach and I narrowed it down to 2 things... Vacuum tree because of all the factory fittings I dont have anymore like the reducers and such... Or timing, but narrowing timing is pretty broad.
 
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