Mystery Plug during restart, help identify please.

[broxma]

Triangular plug. it comes out of the harness at the exact same spot as the knock sensor plug. I cannot find a home for it. It looks very much like the triangular ignition plug which is a bit further down the harness from it. My car is not starting up after my rebuild and I am diagnosing all loose electrical connections.

/brox

 

[Terry Posten]

3 wires in the plug? Comes out of the harness right at the knock sensor? It is for the AC compressor. You do not need it.

Is the starter turning over?

Can you hear the injectors fire and the fuel pump pressurize?

Do you have spark?

 

[broxma]

AC, that makes sense.

The FPR is showing about 40 PSI fuel, I cannot hear the injectors firing. I checked spark at plug 1 and had it. I only changed two things critical to the engine working. The CAS and the ignition. I put the old CAS back on, although I am guessing on the direction it goes into the cam, I guessed dot blade to dot slot if that makes sense. I installed the factory coil pack in place of the COP setup to rule that out. I think it is fuel but don't know what to check to find out if the injectors are firing. The injector resistor pack is hooked up although I am not sure if it needs to be grounded. It's bolted to the firewall out of the way.

/brox

 

[Terry Posten]

Resistor pack does not need to be grounded.

Do you have a can of start fluid? Squirt some into the TB and see if it sputters.

 

[broxma]

I don't. I'll have to pick some up tomorrow.
I have put myself pretty deep in a hole with this car. It's been 5 months of work leading up to this weekend, but I have changed so many things on the car it is going to be almost impossible to find the one new thing that is screwing everything up.

I'll keep at it.

/brox

 

[grocery_getter]

You can use a noid light or any 12v led across the 2 injector harness female pin. Or even one of those voltage checking screwdriver look alike tool with fuse inside them and an aligator clip attached to it. The injector harness has 2 pins. Of you can check it with a multimeter. One of the pin is +12v with key in the on position with engine not running. The other is ground that the ecu provides. You can put the multimeter on the 2 pins and have someone crank the car and you should have oscillating 12 volts or light signal.

I know that you check for spark on number 1. Are you sure about that? Reason I say is because a lot of people confuses the AC connector plug with ignition connector plug since they are both triangular with 3 pins.

How about fouled plugs? That will make starting very hard if not impossible. Checked the condition of the plugs?

 

[grocery_getter]

I have also seen people confuses the injector resistor pack connector with the isc connector. They are both 6 pins connectors and actually fit each other. You will know for sure if you have these 2 plugs mixed if you can't find +12v on one of the injector harness pin with the key on ON and engine not running.

You know how to read the wiring diagram? Read them and go thru the schematic for the injector and ignition.

 

[broxma]

I'm confident I haven't confused the plugs. Considering the lengths that would be required to do so given their location on the harness itself, I would look upon anyone who did with a bit of skepticism.

I should have stated, this isn't my first day. What I mean by that is, I've been working on these car for over 15 years. Given the time=experience premise, my argument is that something is wrong which I have not yet encountered. The counter argument is, I have presumably encountered most of it. This is what worries me. I have a feeling it is something simple but I am unable to find it. I need another set of eyes to look it over.

/brox

 

[Hertz]

Did you line up the CAS with cyl 1 at TDC? Frustrated? Flip that thing 180 and try again.

 

[broxma]

I have gone ahead and taken a video of what the car is doing.

View My Video

The noise in the background is the Evo which is running right behind the GVR4 as the Battery source. I have 13v at the terminal in the GVR4 with the Evo hooked up.

I switched the firing order once but I suppose it may be wrong twice which is possible. Take a look at the video and tell me what you think.

/brox

 

[Terry Posten]

That motor is not spinning over fast enough to start up and it sound like the starter is grinding against the flywheel. Or bad start motor.

What I would do is remove the spark plugs and spin the motor over. It should spin very quickly. And then you can see if fuel is pumping into the motor.

Kill the fuel by unplugging the MPI relay and spin that motor over for a while if you have not pre-pressurized the oiling system (complete motor rebuild right?).

 

[broxma]

Yes full rebuild. In addition, it has Evo pistons now so the compression is higher. I'm going to pull the plugs and see if it is the compression which is slowing down the starting cycle. The starter is old but did functionally work before I pulled it off.

The flywheel and clutch are both new as well not that it matters. I have not bled the clutch line but the car is in neutral which should provide the same resistence as if the clutch were bled and depressed by my count.

/brox

 

[Terry Posten]

I never start my car with the clutch pedal pushed in. It is really hard on the thrust bearing (Clutchnet 3X PP). Especially if you don't have any oil pressure. Take a new vid w/o spark plugs and let us see how fast the motor is spinning.

 

[broxma]

As expected, with the plugs removed the motor turns at a normal rate. I cannot however see any gas coming out of the plug holes as expected. I am curious as to how I have fuel pressure but no fuel. I smell gas but only faintly.

Edit, the pedal isn't pushed in, the line is not bled. The pedal is on the floor but only due to lack of pressure and needing the clutch switch active. Video coming up.


/brox

 

[Terry Posten]

Have you ever had the ECU serviced?

Can you swap in a different ECU to see if that may be the cause? Also check all the fuses. It is really simple to pop a fuse with all the work that has been done since you parked it last.

 

[broxma]

The ECU has just had a KD chip installed for the 2G MAS and Evo Injectors. The car ran on that chipped ECU before the build. I checked the fuses first and didn't find any blown. I am currently leaning towards clogged injectors due to the new rubber lines. I am only just now seeing some gas in the cylinders from all the starting and I expect to see it shooting out of the plug hole which I am not witnessing.

Here is the no plug video.

View My Video

I'm going to remove the fuel rail and check on a new starter motor. I may in fact have a spare.

/brox

 

[Terry Posten]

Yeah, that starter sounds tired or mis adjusted.

Kevin's cars tranny had some play in the starter mounting and if you did not pull the starter up away from the FW while tightening down the bolts, it would sound VERY bad.

Good luck.

 

[broxma]

I put the coil pack back in place, dropped the plugs in and turned it over at which point a noise, I can only describe as a loud pop was heard and now the car has lost all power. No fuses are blown, no smoke, no smell. Just a pop and no power.

Better by the minute.

/brox

 

[broxma]

And suddenly the sky parted and the sun broke through the clouds. Two ravens previously sitting on the backyard fence disappeared for what appeared to be no reason what so ever. An ice cream truck drove by with children running behind laughing and playing while a monkey danced on the roof of the truck throwing candy at them. The phone rang and my mother told me she had just won the lottery and my sister, currently in nursing school had accidentally stumbled upon the cure for cancer. All the bugs flying around in my garage unanimously agreed to vacate the premises and prevent any further bugs from returning.

And the power came back on I turned the car over and it started right up. Absolutely nothing changed.

/brox