Got no spark!!!

porsche944god · 09-19-2010, 05:00 PM

1987 supra was looking for amp draw....pulled fuses out and nothing changed replaced interior fuses and wahla! no spark but got fuel need help i think its computer but not sure

btwilson86 · 09-20-2010, 12:57 AM

my first guess would be the 15 amp efi fuse in the engine bay

porsche944god · 09-20-2010, 01:06 AM

well it has no blown fuses whatsoever and the main relay under the hood is not clickin on or off jumped it it would start but rev up to 2000 then back down 1100 then back up.....without it jumped the car has no spark but is getting fuel

CanadianBak'inSupra · 09-20-2010, 12:51 PM

try putting in a new main relay then.
think there like 20 $

porsche944god · 09-20-2010, 03:11 PM

They relay is still good i moved it to a spot on the inside panel and it clicks....i have power on the "engine" fuse and ecu-ig fuse both sides like i said will run as long as the main relay is jumped will not if everything is like it should be ....i actually while it was running took the ecu-ig fuse out and nothing happened also did the same with the engine fuse. If it is the computer i have no idea how it would have burned up, also doesnt it mean the ecu is bad when u turn on the key and the check engine light does not light up? cuz it did b4 i started tryin find the amp draw.

btwilson86 · 09-20-2010, 05:36 PM

It sounds like you must have a break in the wiring after the EFI fuse. Once you jump the relay directly, pulling the fuses wouldn't do anything because they are no longer supplying the power, your jumper wire is.

Check for voltage at the + input for the relay's internal coil (normally an 85 or 86 if it's marked). If there is power, check the relay coil's ground wire for continuity with the chassis ground. One of those should fail, when it does start tracing that wire to find either the faulty switch/relay or break in the wire

porsche944god · 09-20-2010, 05:46 PM

I can pull the efi fuse out and it dies .....and there is only power on one of the terminals where the relay goes but its hard for me to think there is a break anywhere tho considering the car ran fine up until i pulled the fuses out of the interior panel....and there is no check engine light could that be caused by faulty ecu? From what i gathered from schematics that light circuit comes directly from ecu.

porsche944god · 09-21-2010, 03:08 PM

Well thanks for your help, some how i over looked the 7.5 ig fuse in the inside fuse panel lol of coarse how it was blow was hard to see now im back to square one......i need a w58 tranny!

CanadianBak'inSupra · 09-21-2010, 10:50 PM

good luck.
ive been lookin for one for my mk2 for months...

09-19-2010, 05:00 PM	#1
porsche944god Stock Join Date: Sep 2010 Location: tennessee Posts: 18	Got no spark!!! 1987 supra was looking for amp draw....pulled fuses out and nothing changed replaced interior fuses and wahla! no spark but got fuel need help i think its computer but not sure

09-20-2010, 12:57 AM	#2
btwilson86 Super Moderator Join Date: May 2007 Location: Billings, Montana Posts: 1,034	my first guess would be the 15 amp efi fuse in the engine bay __________________ 1989 7MGTE R154 Targa Top White Package w/Blue Interior Driftmotion 57trim CT26, Upgraded Intercooler, 2.25" Hard Pipes, 3" Turbo Back Exhaust with Test Pipe, HKS VPC w/GM 3 bar MAP sensor, APEXi S-AFC, Walbro 255lph fuel pump, ProSport EVO Series Boost / Fuel Pressure / AFR gauges, Lotek a Pillar Gauge Pod, HKS Type 0 Turbo Timer, Eibach Lowering Springs, Tokico Illumina II TEMS struts, custom powder coated Motegi Racing TrakLite wheels

09-20-2010, 12:51 PM	#4
CanadianBak'inSupra Official hall monitor / search nazi - NO SOUP FOR YOU! Join Date: Oct 2009 Location: Canada, BC Posts: 837	try putting in a new main relay then. think there like 20 $ __________________ 1984 supra - 1uzfe - w58 - 4.10 - 1 piece aluminum shaft.

09-20-2010, 05:36 PM	#6
btwilson86 Super Moderator Join Date: May 2007 Location: Billings, Montana Posts: 1,034	It sounds like you must have a break in the wiring after the EFI fuse. Once you jump the relay directly, pulling the fuses wouldn't do anything because they are no longer supplying the power, your jumper wire is. Check for voltage at the + input for the relay's internal coil (normally an 85 or 86 if it's marked). If there is power, check the relay coil's ground wire for continuity with the chassis ground. One of those should fail, when it does start tracing that wire to find either the faulty switch/relay or break in the wire __________________ 1989 7MGTE R154 Targa Top White Package w/Blue Interior Driftmotion 57trim CT26, Upgraded Intercooler, 2.25" Hard Pipes, 3" Turbo Back Exhaust with Test Pipe, HKS VPC w/GM 3 bar MAP sensor, APEXi S-AFC, Walbro 255lph fuel pump, ProSport EVO Series Boost / Fuel Pressure / AFR gauges, Lotek a Pillar Gauge Pod, HKS Type 0 Turbo Timer, Eibach Lowering Springs, Tokico Illumina II TEMS struts, custom powder coated Motegi Racing TrakLite wheels

09-21-2010, 10:50 PM	#9
CanadianBak'inSupra Official hall monitor / search nazi - NO SOUP FOR YOU! Join Date: Oct 2009 Location: Canada, BC Posts: 837	good luck. ive been lookin for one for my mk2 for months... __________________ 1984 supra - 1uzfe - w58 - 4.10 - 1 piece aluminum shaft.

09-20-2010, 01:06 AM	#3
porsche944god Stock Join Date: Sep 2010 Location: tennessee Posts: 18	well it has no blown fuses whatsoever and the main relay under the hood is not clickin on or off jumped it it would start but rev up to 2000 then back down 1100 then back up.....without it jumped the car has no spark but is getting fuel

09-20-2010, 03:11 PM	#5
porsche944god Stock Join Date: Sep 2010 Location: tennessee Posts: 18	They relay is still good i moved it to a spot on the inside panel and it clicks....i have power on the "engine" fuse and ecu-ig fuse both sides like i said will run as long as the main relay is jumped will not if everything is like it should be ....i actually while it was running took the ecu-ig fuse out and nothing happened also did the same with the engine fuse. If it is the computer i have no idea how it would have burned up, also doesnt it mean the ecu is bad when u turn on the key and the check engine light does not light up? cuz it did b4 i started tryin find the amp draw.

09-20-2010, 05:46 PM	#7
porsche944god Stock Join Date: Sep 2010 Location: tennessee Posts: 18	I can pull the efi fuse out and it dies .....and there is only power on one of the terminals where the relay goes but its hard for me to think there is a break anywhere tho considering the car ran fine up until i pulled the fuses out of the interior panel....and there is no check engine light could that be caused by faulty ecu? From what i gathered from schematics that light circuit comes directly from ecu.

09-21-2010, 03:08 PM	#8
porsche944god Stock Join Date: Sep 2010 Location: tennessee Posts: 18	Well thanks for your help, some how i over looked the 7.5 ig fuse in the inside fuse panel lol of coarse how it was blow was hard to see now im back to square one......i need a w58 tranny!

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