No spark mystery on 7mgte

jcgrant4 · 12-05-2007, 11:58 PM

I've lost spark on my 88 7mgte and have hit a wall in my diagnostics. I've got 12v at the 3 coil pack connectors and the ignitor, the resistance on the cps connector pins is all good, but no spark. I tried a back up coil pack, no help. The one thing I can't figure out how to test is for the signals the ignitor sends to the coil packs to fire the plugs. Any ideas? TIA

Jim G

suprra_girl · 12-06-2007, 10:07 AM

have you tried wiggling the cps plug?
what codes have you got?

jcgrant4 · 12-06-2007, 12:44 PM

No codes - I haven't had it started since disconnecting the battery to clean the terminals & check the cables. I'm suspicious of the cps plug/wiring after reading the tons of other posts on this topic, so I'll check that out next.

jcgrant4 · 12-06-2007, 09:24 PM

Okay, cps connector/wires look good, so I decided to check the cps terminals at the ecu. Found 3 plug wasn't seated tight. Now I get spark, but it's weak & intermittent. BTW - the cps did test good at the ecu connector, so now what - ignitor?

suprra_girl · 12-06-2007, 09:49 PM

the cps wires directly at the cps plug generally naff out
usually a good wiggle will get the car going again

robertsws · 08-19-2009, 03:57 PM

hey I have this problem. did you ever figure it out?

shiftysupra · 08-19-2009, 05:50 PM

do you have an auto harnesson a manual? if you do make sure your neutral start switch spliced wiring is good. when you try to start it does it try and start or do you hear just a click noise? more info needed buddy.

shiftysupra · 08-19-2009, 05:51 PM

oh and you really need to check here before posting...

next time read the bible first...

http://www.cygnusx1.net/Supra/Librar...3/default.aspx

robertsws · 08-19-2009, 05:57 PM

I appreciate the link to the TSRM, been there. I just don't have spark. that's it.

shiftysupra · 08-19-2009, 06:21 PM

so it tries to start (and turns over) but just doesnt actually start? have you checked your efi fuse?

it may be the cps. like supra girl said try wiggling the plug or if possible try and swap it with someone else to see if it's faulty

12-05-2007, 11:58 PM	#1
jcgrant4 Stock Join Date: Dec 2007 Location: Stilwell, KS Posts: 5	No spark mystery on 7mgte I've lost spark on my 88 7mgte and have hit a wall in my diagnostics. I've got 12v at the 3 coil pack connectors and the ignitor, the resistance on the cps connector pins is all good, but no spark. I tried a back up coil pack, no help. The one thing I can't figure out how to test is for the signals the ignitor sends to the coil packs to fire the plugs. Any ideas? TIA Jim G

12-06-2007, 10:07 AM	#2
suprra_girl 7M POWAH! ;) Join Date: Jun 2004 Location: New Zealand Posts: 2,312	have you tried wiggling the cps plug? what codes have you got? __________________ Please use the forum to ask your questions as they will get replied to much faster than pming me Pics of my build. "Good girls are just bad girls that don't get caught" Do a diagnostic first!

12-06-2007, 09:49 PM	#5
suprra_girl 7M POWAH! ;) Join Date: Jun 2004 Location: New Zealand Posts: 2,312	the cps wires directly at the cps plug generally naff out usually a good wiggle will get the car going again __________________ Please use the forum to ask your questions as they will get replied to much faster than pming me Pics of my build. "Good girls are just bad girls that don't get caught" Do a diagnostic first!

08-19-2009, 03:57 PM	#6
robertsws 3" Exhaust Join Date: May 2008 Location: Gaithersburg, Maryland Posts: 63	hey I have this problem. did you ever figure it out? __________________ 1991 Supra - Turbo - 5spd 60-1 upgraded turbo Lexus AFM 3" exhaust, 4" tip SAFC 2 550cc injectors (2 sets, venom direct fit, RC engineering) 2.5" intercooler and piping Aluminum radiator w/dual electric fans ARP bolts w/MHG Full-auto turbo timer Fidanza Flywheel & Stage 2 Clutch spark plugs and wires. power steering pump cold temp start switch engine top end rebuilt transmission opened up and inspected at a tranny shop when the flywheel and clutch installed last week.

08-19-2009, 05:57 PM	#9
robertsws 3" Exhaust Join Date: May 2008 Location: Gaithersburg, Maryland Posts: 63	I appreciate the link to the TSRM, been there. I just don't have spark. that's it. __________________ 1991 Supra - Turbo - 5spd 60-1 upgraded turbo Lexus AFM 3" exhaust, 4" tip SAFC 2 550cc injectors (2 sets, venom direct fit, RC engineering) 2.5" intercooler and piping Aluminum radiator w/dual electric fans ARP bolts w/MHG Full-auto turbo timer Fidanza Flywheel & Stage 2 Clutch spark plugs and wires. power steering pump cold temp start switch engine top end rebuilt transmission opened up and inspected at a tranny shop when the flywheel and clutch installed last week.

12-06-2007, 12:44 PM	#3
jcgrant4 Stock Join Date: Dec 2007 Location: Stilwell, KS Posts: 5	No codes - I haven't had it started since disconnecting the battery to clean the terminals & check the cables. I'm suspicious of the cps plug/wiring after reading the tons of other posts on this topic, so I'll check that out next.

12-06-2007, 09:24 PM	#4
jcgrant4 Stock Join Date: Dec 2007 Location: Stilwell, KS Posts: 5	Okay, cps connector/wires look good, so I decided to check the cps terminals at the ecu. Found 3 plug wasn't seated tight. Now I get spark, but it's weak & intermittent. BTW - the cps did test good at the ecu connector, so now what - ignitor?

08-19-2009, 05:50 PM	#7
shiftysupra 3" Exhaust Join Date: Jan 2006 Location: Arizona Posts: 96	do you have an auto harnesson a manual? if you do make sure your neutral start switch spliced wiring is good. when you try to start it does it try and start or do you hear just a click noise? more info needed buddy.

08-19-2009, 05:51 PM	#8
shiftysupra 3" Exhaust Join Date: Jan 2006 Location: Arizona Posts: 96	oh and you really need to check here before posting... next time read the bible first... http://www.cygnusx1.net/Supra/Librar...3/default.aspx

08-19-2009, 06:21 PM	#10
shiftysupra 3" Exhaust Join Date: Jan 2006 Location: Arizona Posts: 96	so it tries to start (and turns over) but just doesnt actually start? have you checked your efi fuse? it may be the cps. like supra girl said try wiggling the plug or if possible try and swap it with someone else to see if it's faulty Last edited by shiftysupra; 08-19-2009 at 06:30 PM.

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
No spark issues	DDBT	MKII Supra	2	01-06-2009 07:08 AM
7mgte swap no spark	supra4life1386	MKIII Supra	5	11-27-2008 07:57 PM
NGK Spark Plugs	91 Supra	MKIII Supra	5	08-07-2007 03:52 AM
Spark plugs & WIRES	HEMAN	MKIII Supra	2	11-03-2006 05:31 AM