spark issue please please please help!!
 

i have an 87 supra turbo (7mgte). and for the past few months i have had a problem with spark. i would hop in 2 minutes after previously driving it and it wouldnt start. then i would replace the coils and it would start again i replaced them twice now and its still doing it. i just recently got my hands on a really nice multimeter and tested all the coils and every single one that i still have that was supposedly "bad" and they all checked out (.3-.5 ohms of resistance).
so now im super confused and i dont know what to do. any help would make me very very happy as this is my only car and it hasnt been running.

please help

I don't know what you're using as a reference, but your measurements sound right on.

Here's a test procedure:
http://www.cygnusx1.net/Supra/Librar...aspx?S=IG&P=12

Please post MKIII specific questions in the MKIII section. I'll move this thread.

ya i know and thanks for moving the thread. i wanna know what do do know. should i check the igniter? or what? thank you for finally helping with this matter by the way

Do you have any diagnostic codes stored? If so, what?


You should go through the troubleshooting chart for ignition problems in the from of the section I linked to. The diagnostic work flow Toyota specifies does work really well. As this is an intermittent issue it probably will be abit harder to diagnose... try to recreate the conditions under which the faults occur: If they usually happen after the car had been run for a while try warming the parts with a hair dryer or hot air gun (set on LOW). If the problems occur when cold, make sure the parts being tested have had time to cool sufficiently.

Troubleshooting work flow:
http://www.cygnusx1.net/Supra/Librar....aspx?S=IG&P=3

Sure, the igniter is a possibility, so is the CPS and ECU. Start with the work flow.

i get codes 12, 14, 21,(maybe 41, i dont remember), 42, 51, 52. i was wondering if it might be the igniter? or maybe the cps (cam position sensor)?

Good god man... :eek3:

Start with fixing the code 41 and the code 12 and code 14. So, yes, troubleshoot the igniter, the CPS and the TPS wiring. Other than the ECU most of those codes have NOTHING in common. It's very unlikely that you're looking at one problem.

tps is good, and the wiring to the cps is all jacked up. how do i test it? i bought a new igniter off my friend ($10 so why not haha). thank you

How is the wiring "all jacked up"?? If the wiring is "jacked up" sufficiently that may be the only thing you need to fix... didn't think it was worth mentioning?

Wiring diagram: http://www.cygnusx1.net/Supra/Librar...x?S=Main&P=040

well the insulation on one of the wires is burnt to a crisp and almost completely off, and all the wires are indistinguishable (they are basically fused together). is there a way to test the cps??

oh and thank you again for your help :D

Sure, you can test the CPS... but it's pointless if the wiring is jacked... why don't you start fixing the problems instead of ignoring them and looking for others? You've wasted a LOT of time by dicking around and ignoring and failing to mention the damaged wiring. :frown: