possible wiring problem??

[Project Draven]

well all i still havn't figured out whats going on with my 90 tsi and apparently noone else is writing back to me in my previous thread so here it goes......i am having a spark issue and i have tried to replace everything now all i am getting from the coils is a clicking sound.......we tried all my old components....power transister.....cas...ecu....in my buddys car and everything works fine......spark and all.....so this leads me to believe i have a wiring problem somewhere but i don't know where to go from here can someone please point me in the right direction i mean this is straight up frustrating me or could someone tell me where to look and to get this problem of mine finally solved....i mean please everyone i am going crazy here and i know someone out there knows whats possibly messed up here


any help will be greatly appreciated

thanks in advance

brandon

 

[luv2rallye]

Assuming nothing's been modified/changed on the ignition circuitry.
First pull plugs 1 & 2, clamp them to some engine metal and reconnect their spark cables (so you can tell if getting spark).
Now disconnect power transistor (PT) connector.
Next turn key to ON and see if you get +12V on ignition coil pin 4 (black/white wire).
Now ground PT harness pin 1 (yellow/green) for a second. When you remove ground you should see one of the plugs fire.
Now ground PT harness pin 6 (yellow/black) for a second. When you remove ground you should see the other plug fire.
If all this works turn key off and check continuity from PT pin 3 (black) to ground and to battey negative.
If ok check continuity from PT pin 2 (yellow) to ECU pin 54 (yellow).
If ok check continuity from PT pin 5 (yellow/red) to ECU pin 55 (yellow/red).
And get back to us.

ECU pinout: http://www.vfaq.com/mods/ecu-harness-1G.html

 

[Project Draven]

does the ecu have to be hooked up for this.... i am just wondering so i don't fry it

and for contunity do u mean a constant reading...or varying?

 

[steve]

Checking continuity means to measure the resistance between two points and make sure you have a low resistance (0 ohms is good). You looking for the same reading as when you touch (or short) the two meter probes together.

Steve

 

[Project Draven]

does the ecu need to be plugged in for the transister check before i do the signal continuity ??

 

[Project Draven]

but hey can i use this to test for continuity or do i need a different one??

 

[adiffrentcity]

That should be fine just set it to low dc ohms

 

[steve]

That will work fine. Set it to the x1 ohms scale. The harness needs to be disconnected at both ends to measure continuity of the wires. (ECU and Power Transistor)

Steve

 

[Project Draven]

well i am getting power to what appears to be white or yellow with a green stripe on the transister plug.....and i am getting power to the white and black wire on the coil plug and i have my ecu disconnected not sure if that makes any difference

 

[Project Draven]

seen some pretty blue light when i tried to ground that yellow/green stripe wire like the directions above any ideas ??

 

[Project Draven]

well the continuity test was as follows.........pin 55 needle moved all the way over to zero.....pin 54 (think i did it right) needle doesn't move at all......i did this with the battery disconnected....does it need to be powered on ???....i tried pin 2 from (pt) with pin 56 (Ecu) and i got the needle to move to zero so whats goin on here? i also check the pin 3 for ground on (pt) to a ground source and then to the negative terminal and it went to zero for both i'm gonna check the grounds on the ecu side as well

 

[luv2rallye]

No it must not be powered on. Disconnecting the battery is a good precaution for the continuity test although it shouldn't matter if you have both ends of the same wire (connectors) off. But in case there's a short or you touch the wrong pin it's always a good idea.
There must be continuity (ie. a connection) from PT pin 2 (yellow) to ECU pin 54 (yellow) or 2 plugs will not fire (either 1&4 or 2&3). Recheck to make sure. If still not, wiggle the ends of the wire near the connectors to see if there is an internal break. The wire must be broken somewhere if no continuity. Usually in or near the connector. You can stick a safety pin through the insulation (to touch the wire inside) at different points along the wire to find the break (also bending the wire sometimes will locate it) while measuring continuity.

When you grounded the PT yellow/green a connection spark (pretty blue light) there is normal since you just energized the coil with around 10 amps. But the plug should have fired when you removed it - did it? Also the same with the PT yellow/black - did it? This is a test of the coils.

 

[Project Draven]

no they didn't maybe i didnt have it grounded properly....whats the best way to ground those pins?

 

[luv2rallye]

Well you can either short the pin to engine metal or to PT pin 3 (black) since it goes to ground. If the plugs don't fire [note they must have their spark cables on and have their casings connected to (eg. clamped) to engine metal and coils hooked up], try doing the same thing on the same wires at the coils (which is where these PT wires go). If still no spark, your coils are bad. This is all with the battery connected and key to ON (you can leave the ECU disconnected if you wish for this test).

 

[Project Draven]

oh hey i think i figured out why i had continuity on pin 56 because i was looking at the diagram wrong i was connecting it to 54 not 56 and 56 i thought was 54 stupid me but i got continuity to pins 54 and 55 so moving on .....also i check the ecu grounds on the battery and on a ground source.(bolt) pin 106 is fully at zero.....pin 101 is close to zero but a few notches off

 

[Project Draven]

but i can't understand i bought brand new coils for my car and they did the same exact thing as my ones i have now not i just hooked them up not sure if they had t be installed on the intake mani to work??....you said i have to have the spark plug cables on to do this can i just look at the coils?

 

[Project Draven]

can i test the continuity of my power transister wires to my coils?

 

[luv2rallye]

...not sure if they had t be installed on the intake mani to work??

I hear conflicting reports on this. Some say they must be in the original location on the mani (I assume to complete the magnetic field circuit on the coil secondary to the plug casing which is what I would also think) yet others claim they work anywhere [STEVE: What do you say on this?]. Try putting them in the original place and see.

....you said i have to have the spark plug cables on to do this can i just look at the coils?

Not sure what you mean by looking. The spark plug cables need to be on to the plugs so you can see if the plugs are getting spark. Just looking at the coils proves nothing. You can measure the coils resistance if you want when disconnected. Should be in range 0.77-0.95 ohms across pins 1 & 4 as well as across pins 2 & 4. Across each coil secondary (where spark plug cables 1 & 4 go as well as cable 2 & 3) you should get in range 10.3k-13.9k ohms. If outside this range the coil is bad. But inside this range doesn't necessarily mean the coil is good - you have to fire the coil as I've described to know.

Yes you should test the continuity of the wires between the PT and coils - they are the yellow/black and yellow/green wires.

 

[Project Draven]

well i took out my coils and i noticed one of the nuts for the wires came loose on the back so i tightened it up and i tried ## little test again you showed me rally and all it does is spark from the transister pin so is there some sort of problem possibly with the transister plug

 

[luv2rallye]

You mean like your post 10 and my answer in post 12?
Here is how you can test the PT: http://www.dsmtuners.com/forums/showthread.php?t=229419.
However, it's sounding more and more like the coil is bad to me. You do have the plugs hooked up to the coil like I said right? And you tryed it in the original location?

 

[Project Draven]

yeah i tried your method and all i am getting for spark is the sparking coming from the transister plug i'm buying the coils again tomorrow and i will see and i am gonna take the voltmeter with me so i can test them right in the store

 

[steve]

I hear conflicting reports on this. Some say they must be in the original location on the mani (I assume to complete the magnetic field circuit on the coil secondary to the plug casing which is what I would also think) yet others claim they work anywhere [STEVE: What do you say on this?]. Try putting them in the original place and see.

I assume we are talking about the coils? They need a common ground between the two spark plugs. The magnetic field is coupled between the primary and secondary but there isn't any electrical connection between the primary and secondary.

So what was the question, I haven't been following all the discussion. The only thing I wanted to make sure of was that we all were refering to the 90 schematics and wire colors since the 91+ are different in this area.

 

[Project Draven]

rally told me a way to test my coil packs by unplugging the transister and grounding the coils manually to see if they fire....and i noticed that my pin with the yellow and green stripe wire on the transister connector for one of the coils ground has a 12v source (picture in post 9)and i keep trying to ground the coils to see them fire and the only thing i see is blue spark from the transister connector where i am trying to ground it? he told me it is normal so i am guessing it is and i have the ecu unplugged because i don't wanna fry it again

 

[steve]

Thw one 90 diagram I have shows the PTM wiring as:
Pin 1 (Yellow/Green) Coil A
Pin 2 (Yellow) ECU Coil A In
Pin 3 (Black) Ground
Pin 4 NC
Pin 5 (Yellow/Red) ECU Coil B In
Pin 6 (Yellow/Black) Coil B

If the coil is good and wired correctly both the Yellow/Green and Yellow/Black wires should have 12v on them when the ignition is on and the PTM is disconnected. The Black/White wire to the coils on the 4 pin coil connector is 12v into the coils.

If you ground either of the Yellow/Green and Yellow/Black wires your likelt to see a big spark. The Coils pass several amps (up to 20A each) when they are charging. Disconnecting the groud will also generate a big spark since the coils want to continue charging.

This is pretty much what luv2rallye said back in post 12.

Steve

 

[luv2rallye]

Both the PT connector yellow/green (pin 1) and yellow/black (pin 6) will read +12V on them because they are on the load side of the coil primarys when no current is flowing. You see +12V because you are reading what's on the other side (through the coil's primary) which is connected to the ignition switch (+12v). When you ground them you are doing the same thing as the PT does when it turns on (energizing the coil) and when you then remove the ground you are doing the same thing as the PT does when it turns off (discharging the coil). Applying the ground manually with a wire creates a spark there due to the high current (10 amps) that you just applied. It's like the spark you get when you plug in your hair dryer when the switch is already on.

Update:
Steve, your post got in while I was creating this one which is why it sounds somewhat repetitive (hadn't seen yours yet). BTW I am using 90 Eclipse schmatics from Mitchells so I know I have the right colors.