No spark on my 89 turbo

TheMoneyPit2

New Member
Sep 3, 2008
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41
Montgomery, NY
My car used to run great but one day it wouldn't start. Now, over a year later I've replaced the plugs, cps, and igniter and still have no spark. I can't find any broken wires or blown fuses. Im not sure what else to check but was hoping that someone in the New Paltz area could lend a hand. Thanks, Matt
 

Crazybobmundo

New Member
Mar 24, 2006
105
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Nashua, NH
Try these tests if you don't get codes.
http://cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?S=IG&P=10

if your Engine light doesn't blink acording to the TSRM;
http://cygnusx1.net/Supra/TechTips/engine_error_codes.aspx

Maybe your ECU isn't powered. I had the same issue. My ECU was not getting power to pin +B and B which should be powered when the IGN switch is turned to on.
Heres the diagram: http://cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?S=FI&P=52

If thats the case either your EFI main relay is faulty or your circuit opening relay. Atleast thats what my no spark issue was.
http://cygnusx1.net/Supra/Library/TEWD/MK3/manual.aspx?S=Main&P=46
http://cygnusx1.net/Supra/Library/TEWD/MK3/manual.aspx?S=Main&P=47

I don't know if you're capable of reading that but it helped me a lot.


Again, only go this far IF the simple stuff has been double and triple checked, like fuses, connection, etc.

Oh and don't forget the grounds. The one ground that caused some issue with my spark was the one that gets bolted to the bottom of the intake manifold. Those are the TCCS grounds and what not.


I really hope that helps. I wanted to kill myself if I couldn't figure it out.
 

Jetfixr757

Sleeper
Mar 30, 2005
259
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16
60
Cocoa, Florida
mk3sons;1512138 said:
i had the same problem i would check to see if the wires are properly attached to the connectors.

Check your ground wires mine did that and i found the ground wires under the intake manifold slack just a little, retorqued and fire,...
 

TheMoneyPit2

New Member
Sep 3, 2008
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41
Montgomery, NY
I tried the spark test and got nothing. I also rechecked the grounds and connections. When I jump the diagnostic ports as per the tsrm I get no check engine light. I really hope this is something I'm overlooking. Any other suggestions? If anyone is local and willing to help I've got beer. Thanks
 

Crazybobmundo

New Member
Mar 24, 2006
105
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Nashua, NH
Im telling you I bet if you put a voltmeter to +B and B of the ECU you probably wont get 12V when the Ign switch is on. I had the saaame problem. Hell just swap out that EFI relay and see if that works.
 

IBoughtASupra

New Member
Mar 10, 2009
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Queens, NY
With the ignition on, does the "Check Engine Light" come on? If not, that means that the ECU is not getting power, or it is bad. I have only seen on bad 7M ECU. The person had the black piece by the valve covers off since it was broken and it looked like some wires touched. When I opened the ECU, it was black in one part and smelled burnt.
 

TheMoneyPit2

New Member
Sep 3, 2008
7
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41
Montgomery, NY
No the CEL never comes on. Is it possible that the ecu is bad causing no spark but everything else works? I also tried replacing the main relay but that did nothing.
 

IBoughtASupra

New Member
Mar 10, 2009
4,455
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Queens, NY
T-MA71, that is what I told him. If the "Check Engine Light" does not come on, it means that the ECU is either bad or is not getting power. Obviously, we all would check for power before we try a different ECU. Like Crazy said, check +B and B to see if you are getting 12V when the "Ignition" is on. If you are getting power, then the ECU is bad. If you are not, try checking the "EFI" fuse under the hood.