Coil pack and Igniter

[Boombastic]

Don't worry, I searched on here but I really didn't find the info that I needed. Anyways, I have 86.5 turbo. My car was running and starting fine until today. I went for about an hours drive to a store today. My car was about 80-90 celcius which is normal for me. About five minutes to go before I arrived, my temp spiked to between 95 and 115 celcius! I got to the store and was there about half an hour. Came out car fired up, temp was about 85 celcius. I am rolling out of the parking lot and the temp is still spiking. Then my car just dies, but accessories are still good and battery voltage is still above 12.5. It wouldn't start at all, just kept cranking over.

So I knew my thermostat was pooched, but I couldn't take it out because of lack of tools. I sat for about 15 minutes and let the car cool which seemed to do the trick, cause it fired back up. So I was on my way home. About ten minutes from leaving the parking lot the temp spikes again this time ranging between 90 and 110 celcius, mostly at 100 since it was highway. I ended up making it all the way home. Took that thermostat out and ran the car some more. Everything was fine, starting and running.

Here is fun part. I go inside for about half an hour, come out and go to start, nothing..... just keeps cranking over. The temp was about 80 celcius. So I let it sit some more and tried it again when the temp was about 60 and it started. Since then it has been intermitant between starting and not starting.

I have checked out my igniter box and found that coil pack 1 and 3 are getting 8.90 to 9.10 volts and coil pack 2 is getting full voltage (about 12.3). I am just wanting to make sure that my igniter is messed up and not something else, wiring coming into the box is fine.

An input is much appreciated. Thanks.

 

[ForcedTorque]

Sounds like your car has multiple problems.

 

[plaaya69]

How is the small coil pack wiring harness? Also I would check the resistance in the coil's.

 

[Boombastic]

Sounds like your car has multiple problems.

Yea really crappy thermostats. I don't think I am going to use one, don't need to now that it is warmer out. I heard TRD thermostats are good.

 

[dumbo]

Sounds like your car has multiple problems.

Yup.

Check your codes. - http://cygnusx1.net/supra/Library/TSRM/MK3/manual.aspx?Section=FI&P=23

Check your wiring, IIRC there is only a 4 wire plug going to the "small" harness that goes to the coil packs right?

I would test, or get a new thermostat too.

EDIT: You want a thermostat.

 

[Bass_Man]

Take one spark cable from coil and then cranking . You need to see small sparks from middle of coil to something around and then put cable back on coil and go to next . Check every coil one by one by this way . If there is a spark on every coil ( cable ) do no touch anything . Of course you need to take one friend for this job . One of you to watch and one of you to cranking .
And stay away from coil when cranking ! You need only few revolution to see the spark ! Do not stay minutes on starter !

 

[Boombastic]

Thanks for the help soo far, as for my heating issue I said in my mini story, I just needed a new thermostat which I knew, but I was out in the middle of nowhere when it started happening. As for the the wiring. I have power coming from the ECU to the igniter (small plug) but it still reads low on the coil pack #1 and #3 at only about 9.0 volts. Whereas number #2 coil pack has 12+ volts. I have the same amount of current at the igniter as I do at the plug ins for the coil packs.

 

[ForcedTorque]

From your sig............

"86.5 Hardtop, LHD, Single turbo, 60,xxxish on engine, ARP's on the head, Greddy MHG 1.5mm"

So was this JDM motor properly prepped for the MHG? What was done? How was the 1.5mm size determined?

 

[Boombastic]

From your sig............

"86.5 Hardtop, LHD, Single turbo, 60,xxxish on engine, ARP's on the head, Greddy MHG 1.5mm"

So was this JDM motor properly prepped for the MHG? What was done? How was the 1.5mm size determined?

Yea it was properly prepped, the guy just wasn't sure of how many kms he has put on the engine since the rebuild, he knows it is around 60 000.

 

[Boombastic]

Anyways I only said my temps because I might have melted something, something small outta the way that melts easy. But I checked all that and I have power where it should be.

 

[Bass_Man]

Ok , but do you have a spark ?

 

[Boombastic]

Ok , but do you have a spark ?

On coil pack #1 and #3 I have a very weak spark, so weak you can't even see it sometimes. On coil pack #2 I have full spark. I am 95% confident that it is my igniter box.

I am just wondering if 9.0-9.1 volts on coil packs #1 and #3 is enough to start it. I don't think so, but not 100% sure.

Thanks everyone.

 

[Bass_Man]

On coil pack #1 and #3 I have a very weak spark, so weak you can't even see it sometimes. On coil pack #2 I have full spark. I am 95% confident that it is my igniter box.

I am just wondering if 9.0-9.1 volts on coil packs #1 and #3 is enough to start it. I don't think so, but not 100% sure.

Thanks everyone.

OK but if you have some good spark even only on two cylinders ( coil pack#2 ) they will try to start . Do they try to start or you just cranking and nothing happen ?
From what you say for me this is more like problem with el. installation ( cables , fuses , contacts , ground ( - ) and + ) .

 

[Boombastic]

OK but if you have some good spark even only on two cylinders ( coil pack#2 ) they will try to start . Do they try to start or you just cranking and nothing happen ?
From what you say for me this is more like problem with el. installation ( cables , fuses , contacts , ground ( - ) and + ) .

Yea it tries to start, like sputters and then i release the key and it dies.

 

[Bass_Man]

Now I saw in manual schematic for ignition and all coils + igniter are connected to B+ via contact key .
http://www.usefully-info.com/7mgte/manual/25_D.pdf
on 35 page you can see schematic .
And if you measure between 4 ( B+ ) and chassis you need to get 12V . But if you measure between 4 ( B+ ) and 1,2,3 on non working car ( only on contact ) I am not sure what you need to get .

BTW: I can measure on my what are voltages :icon_bigg .

 

[Boombastic]

Now I saw in manual schematic for ignition and all coils + igniter are connected to B+ via contact key .
http://www.usefully-info.com/7mgte/manual/25_D.pdf
on 35 page you can see schematic .
And if you measure between 4 ( B+ ) and chassis you need to get 12V . But if you measure between 4 ( B+ ) and 1,2,3 on non working car ( only on contact ) I am not sure what you need to get .

BTW: I can measure on my what are voltages :icon_bigg .

Ok well, I checked that out but it just seems odd that the igniter is sending 9.0 volts to coils 1 and 3 but it is sending 12+ volts to coil 2. If you could check to see what voltage you are sending from the igniter box to the coils that would be awesome. All I did was take the 4 screws off the igniter box and used the contacts inside to determine how much power I had. It has little abbreviations for what wire does what inside the box. Cheers.

 

[termn8r2000]

I had a similar problem with the intermittent starting / not starting with my 89T. I could drive for days then out of nowhere it would crank all day, but nbot start. Finally I just started checking all of the connections in the igniton system and found that if I moved the wires to the CPS a certain way it would fire. I found that the connector to CPS was bad and repclaced it. Not sure what to tell you regarding the temperature spike, but the only time my temperature would spike was when I had a BHG (Coolant was being forced out of the overflow tank).

 

[Boombastic]

I had a similar problem with the intermittent starting / not starting with my 89T. I could drive for days then out of nowhere it would crank all day, but nbot start. Finally I just started checking all of the connections in the igniton system and found that if I moved the wires to the CPS a certain way it would fire. I found that the connector to CPS was bad and repclaced it. Not sure what to tell you regarding the temperature spike, but the only time my temperature would spike was when I had a BHG (Coolant was being forced out of the overflow tank).

Alright I will check out the CPS. My temp spiking was my thermostat, it is fine now.

 

[Bass_Man]

Ok well, I checked that out but it just seems odd that the igniter is sending 9.0 volts to coils 1 and 3 but it is sending 12+ volts to coil 2. If you could check to see what voltage you are sending from the igniter box to the coils that would be awesome. All I did was take the 4 screws off the igniter box and used the contacts inside to determine how much power I had. It has little abbreviations for what wire does what inside the box. Cheers.

Hmmm ....... actually correct schematic is on page 34 :sarcasm: and I measure between 1,2,3,4 points on ignition coils and B- and I get 12.2 volts . And after little thinking I understand there is no way to be something different when engine is not started ( only starter key in position ON ) . Because one first side coils are direct supplied from B+ and their other end in this moment is not connect anywhere and there is no current flowing via coils ( or current is very small , becuse engine is not running ) . At this time igniter just do nothing and do not supplies coils with voltage and there is no flowing current . If you measure by this way and get different readings this need to show connection/connectors problem between igniter and coils . There is one connector from igniter side , also one near to coils and one small on each coil . Check all of them and on all pins you need to get same voltage .

 

[Boombastic]

Hmmm ....... actually correct schematic is on page 34 :sarcasm: and I measure between 1,2,3,4 points on ignition coils and B- and I get 12.2 volts . And after little thinking I understand there is no way to be something different when engine is not started ( only on contact ) . Because coils are direct supplied from B+ and their other end in this moment is not connect anywhere and there is no current flowing via coils in this moment ( or current is very small ) . And in this moment igniter just do nothing . I mean in this moment igniter do not supplies coils with voltage and there is no flowing current . If you measure by this way and get different readings this need to show connection problems between igniter and coils . There is one connector from igniter side , also one near to coils and one on each coil . Check all of them and only on contact you need to get same voltage on every cable .

Alright I didn't check them on contact before, makes sense. I will get on that. Thanks.