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Thread: No start after motor swap. Thoughts?

  1. #1
    Join Date
    Aug 2014
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    76

    No start after motor swap. Thoughts?

    Alright guys so i have finally swapped the motor over in the supercoupe! All vacuum lines seem okay, the installation looks neat and tidy, the car is ready to go!

    Or not, no start. The motor turns over but has absolutely no signs of starting up.

    I have tried pulling codes from the car, it gives me nothing. Here is what i have so far!

    Fuel pump primes fine. Tried to fire using easy start and got nothing. Coil pack and wires are plugged in their respective positions. Fuses are okay. The ignition harness is all plugged in tightly and in the correct places. 2 engine grounds have been bolted back to their original places on the new motor.

    I have a suspicion it has something to do with the crank position sensor as the plug was damaged on the new engine during transit, and damaged wiring on the old motor during removal. Neither of these seem to change anything.

    Before i drop coin on a new sensor, is there anything i may be overlooking? Even with no codes, could this sensor still be at fault?

    Neill

  2. #2
    Join Date
    Dec 2007
    Location
    Salem, OR
    Posts
    6,295
    Quote Originally Posted by superpoop View Post
    Alright guys so i have finally swapped the motor over in the supercoupe!
    Did you get creative and paint the accy. brackets or the heads, by any chance?

    Did you check the fuel shutoff safety impact switch in the trunk?

    Is the multi-wire ignition switch down on the side of the steering column new/in good shape?

    Is the upshift light or check engine light on while cranking?

    For a no start check (example '89), see:
    http://mnharms.com/tutorials/disnostart/

  3. #3
    Join Date
    Apr 2012
    Location
    Dallas, TX
    Posts
    412

    Deja vu

    The last engine swap I had the same issue. Even after triple checking the sparkplugs wiring and hook up to the coils, I still screwed it up. Remenber 5 and 6 are swapped.

    http://www.sccoa.com/forums/showthre...t=Firing+order

    The other issue I had was the harmonic balancer not being fully seated. A slight pull back will keep the crankshaft sensor from seeing the harmonic balancer ring. Otherwise follow the link posted by KMT.
    Last edited by Falcon20x; 09-04-2017 at 06:59 PM.
    Check out my 1993 White Auto SC page for video on how to ..
    1990 35th anniversary SC restoration project
    1990 Blue Auto SC

  4. #4
    Join Date
    Aug 2014
    Posts
    76
    Hey guys. Thanks for the input!

    I managed to track it down to being a broken wire in the sensor, which i fixed up real quick to see if it would fire!

    I didnt paint the motor, however i was considering painting the block black before installation yet decided against it.

    I did need to swap the 5-6 spark plug wires on the coilpack though!

    Now i need to chase down a vacuum issue, even though everything looked to be seated exactly where it was, i have zero vacuum at idle. Time to search the forum!

  5. #5
    Join Date
    Dec 2007
    Location
    Salem, OR
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    Good news that - glad it's sorted, thanks for the update - be sure the vacuum line to the stock boost/vac gauge is connected at the engine side.

  6. #6
    Join Date
    Aug 2014
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    76
    Quote Originally Posted by KMT View Post
    Good news that - glad it's sorted, thanks for the update - be sure the vacuum line to the stock boost/vac gauge is connected at the engine side.
    I believe it is connected, however im unsure whether it is connected at the correct place.

    The car struggles to idle on its own and needs throttle input to stay alive. It is quite rough and drops to almost zero on the tach immediately after removing my foot from the gas.

    The stock boost/vac gauge reads zero until i press the throttle, then raises vacuum to ~10-15 under light throttle, then maybe 2lb boost under a little more gas.

    I do have a video of its first start if it will help diagnose. The blower sounds louder since the swap too.

    Neill

  7. #7
    Join Date
    Dec 2007
    Location
    Salem, OR
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    Does the boost bypass valve work at idle? Watch the lever - note it's position when the engine is off vs. running. Vacuum should pull it open.

  8. #8
    Join Date
    Aug 2014
    Posts
    76
    Quote Originally Posted by KMT View Post
    Does the boost bypass valve work at idle? Watch the lever - note it's position when the engine is off vs. running. Vacuum should pull it open.
    I found the issue! i hadnt bolted the blower to the intake manifold properly, nor did i tighten up the lower intercooler pipe.

    I bolted the lower pipe up and got a video with a light lope at idle, at this point there was still a small vac leak at the manifold. It still lopes at idle with 18in vacuum.

    https://youtu.be/K7gWtXkFiQA

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