No Spark Help

[87supraturbo19]

Hey guys i have an 87 turbo. After a bhg, i have had the problem of no spark. I get spark on only one cylinder as soon as you crank it and thats it. I have replaced the ignitor. I have ohmed my cps and checked the air gap, good to go. I ohmd my coil pack which is supposed to check .3 to .5, mine checks .8 and it has a crack in it. There is 12v power to both the ignitor and the coil pack, but not to the cps. I wasnt for sure if there was supposed to power to the cps or not. All fuses and ignition switch are good.
Any help on confirming that it is coil pack and/or any info would greatly be appreicated
I would also like to know of all grounds that would affect this. Thankyou

 

[steve_mk3]

Check the wireing at the CPS-
There is a ground wire that goes from the coil packs over to a bolt by the intake.
Also check the ground wires that connect under the intake manifold in the back.

Just where I would start, untill some of the experts jump in.

Steve

 

[87supraturbo19]

what ground wire from the coil? the only wires that are coming off the coil are the three that plug into it. am I missing something or what?

 

[LoveMy7MGTE]

what ground wire from the coil? the only wires that are coming off the coil are the three that plug into it. am I missing something or what?

short wire with eyelets at each end, one end bolts to the head, other goes on one of the mounting bolts for the coils
EDIT*** I think it's white

 

[87supraturbo19]

well bud i can specifically tell you there is no wire coming off of my coil, that could very well be my problem. Other than it ran before w/o one, is it possible i would run without one? For the small time it did run, it ran like crap. It was running rich and was obvoisly a spark issue. thanks for the info. im so eager to go hook one up. There is not a specific stud it goes on is there? hey you wouldnt be able to tell me which wires plug in where on my thermostat housing from top to bottom. I dont know which colors plug in where. I think there is two or three plug-in's i cant remember.

 

[steve_mk3]

The ground wire runs from the coil mounting plate( Ii is on the intake side twards the front) to a bolt that is on the intake side. Since you dont have this wire, as a text I would try grounding the coil plate to a know good ground. Since it would just be for a test it doesnt need to be pretty, just needs to be a good ground.

Hope that helps some.

Running like crap- yup mine did that for about 30 minutes. if everything is connected correctly the ECU needs to relearn( thats what I have been told)

Steve

 

[87supraturbo19]

Thanks. I still need which color wires plug in were on my thermostat housing anyone know?

 

[MDCmotorsports]

Its either the cps or you forgot to install the grounds on the back of the head. There are 4 wires (two and two paired together) that are brown and white. Those need to be grounded, or you won't have any spark.

90% of the time with a no spark issue its either the ground problem or a cps issue.

 

[steve_mk3]

does this help?

 

[87supraturbo19]

Now i have been told those brown and white grounds are on the back of the head and intake. which is it?or both

 

[Idealsupra]

just an FYI the ground from the coilpack to the valve covers is just another example of overengineering from toyota...its NOT needed for the car to run perfectly fine.

sounds like cps wires or another ground as said before...make sure you have the ground from the back of the head to the firewall hooked up

 

[steve_mk3]

Here is a better pic of the thermostat housing

There are several grounds on the car. The one from the coil pack over to the intake area. a group of them that are part of the main engine wireing harness. The group of wires runs down between intake runner 5/4 or mabe 5/6 dont remember exactly. this group connect to the lower intake manifold. ther is a additional wire on the exhaust side that attaches to the head. There is a heavy ground wire that runs from the AC compressor bracket area.

As far as the ground not needed on the coil pack, It couldnt hurt to test it and remove it as a possibilty, I am not disagreeing just saying that it is super easy to test.

 

[steve_mk3]

here is a picture of the intake side with the ground wires attaced to the lower intake manifold. The wires attach to a tab that protrudes on the manifold. you can see them just above and to the right of my finger.


again what I would check and eliminate as possible problems are:
Check the wireing at the CPS-
There is a ground wire that goes from the coil packs over to a bolt by the intake.
Also check the ground wires that connect under the intake manifold in the back.

Hope this helps.

 

[87supraturbo19]

Thanks alot for the help guys, surely I can get it now. I have to wait till the weekend though between my job and college. I know for a fact there is no ground wire on my coil pack to the head. So between that and the other grounds I havent checked. Just maybe she'll run. I have inspected my cps wires and connectors also. Thanks again. Ill keep you posted.

 

[ded7m]

i think i can help, did you get it fix?

 

[87supraturbo19]

I have to wait till this weekend. I dont have that ground wire on my coil. so maybe that will fix it. I dont keep my car at home, no room.

 

[87supraturbo19]

well i got a chance to work on it. i put my on ground on the coil. and checked my others still no luck. i couldnt find the ground on the back of the head. i found a black and yellow ground on side of the block to firewall. im really starting to think its my cps, even though it ohms good.

 

[steve_mk3]

The black and yellow wire is it on the passenger side?
If so that is the ground I am reffering to going from the head-

Have you checked to make sure you have the grounds on the intake side?
These are important grounds, the are for the ecu and others-

As far as the CPS, it can be good, if the wireing from the CPS to oter components is bad, obviously you will have a problem.

Double check all connection- the ignitor, coil packs etc.
Also read- http://www.cygnusx1.net/supra/library/TSRM/ig/IG_01.html

Stev e

 

[87supraturbo19]

i have checked the wiring including the Grounds of the intake. there is no other component it could be other than the cps i guess i will just have to waist $500 and see. Thanks for help.

 

[steve_mk3]

hold on-
befor spending 500-
you could have a bad ecu-
bad ignitor-
Are there any other supra owners near you that you might be able to borrow parts?
also, befor buying new part, check the for sale section on this forum.