Derex'7

iTrader: (16)

Okay, I've narrowed my no start issue down. My question is this though.



I install a known corrupt/bad pfc in my car and I can see the tach bounce and car will fire right up. Even w/the screwed up MAP sensor readings.

Okay so now I remove that unit and install a known properly working unit in my car (All "applicable" sensor readings are in spec), and I can't get no signal from the CAS. Tach stays dead @ 0 rpm. no fuel no nothing, just cranks.

Ok so Riddle me that please.


Going to pull the harness for the nth time tommorow and trace the CAS wiring. This is a single turbo harness too btw. Not one that I stripped down

Also I have rewired stand alone fuel pump.

Is it possible for the PFC to short power to the CAS if lets say one was to remove the fuel pump relay or something? The PFC see's an open circuit in the fuel pump operation

Derex'7

iTrader: (16)

Need someone to answer me this quick question. Shouldn't I get the same ground mV reading on both CAS connectors since they both share the same ground wire?

On G i get 1.8mV the NE reads nothing

Both are getting a + signal of .378 V from ECU w/key on

Need some input here thanks

arghx

iTrader: (3)

the crank angle sensors produce an AC waveform...





The wiring has a ground and shield wire... some wires are in parallel



resistance and airgap need to be in spec:



this is why I don't unwrap harnesses. I might cut some unnecessary plugs but you really don't want to mess with shielded wire.

Derex'7

iTrader: (16)

Ok so from looking down on the Crank sensor which pins should be getting the + signal from the ECU

arghx

iTrader: (3)

If you are referring to the "+" side of the sensors as shown in the diagram above, it is the white wire for the G sensor and the black wire for the Ne sensor. It's in the diagram. You can find which pin goes with which wire by checking out the diagrams for the plugs, which can also be found in the wiring diagrams document:



If somebody started messing with the grounds or the shielding in the harness that could be the source of your problems

Derex'7

iTrader: (16)

yeah but see my issue is this. I cant go by that diagram as I have different color wires coming from the back of the connector. thats y I asked about the orientation from looking above.


I found a diagram though but is this correct?

A being the + and B being the - signal back to ecu

arghx

iTrader: (3)

If you look at that diagram carefully, it is giving the same information as the one I posted above.

Derex'7

iTrader: (16)

Yeah it makes sense now, well anyway I checked for continuity and evrything matched up perfectly. I checked the clearance and I have 4mm of clearance betwwen the crankshaft plate and CAS...So I'm definately thinking thats my problem here

Derex'7

iTrader: (16)

o well Im over it...

Checked clearance w/feeler gauge and it was within spec
Checked for continuity and everything is matching and flowing
Voltage checked fine

Plug up bad pfc car gets signal and starts up...

Plug in good pfc no tach jump, no signal, no nothing...

I give up....going to source an unmolested harness

Derex'7

iTrader: (16)

Yeah some of the shield wire has been tampered with and some of it even exposed.

Would rewrapping the shield harness in electrical tape be a fix?

arghx

iTrader: (3)

Hard to say if it would help. If it's not too much trouble you could give it a shot.

Derex'7

iTrader: (16)

Well its worth a try I guess while Im at it I can add some ground points as it stands right now I only have one in the engine bay and the other two by the ecu.

Also would it hurt to try and also ground the shield wire to the chassis?

Dont think I mentioned it here but when it does start w/the bad PFC it has a steady idle but you can hear alot of popping & missing from the timing

arghx

iTrader: (3)

You can try grounding some stuff, it might help or might not. It's worth a shot.

Derex'7

iTrader: (16)

I think I'm going to find the nearest cliff and drive this car off it

arghx

iTrader: (3)

Please provide vids, preferably in slow motion.

Derex'7

iTrader: (16)

Oh yeah so yesterday I found & fixed abviously what was wrong as you can see from the pic below.

Those are the G & B wires coming from the CAS (NE) connector.


Cool everythings hooked back up properly now (check & recheck) so I go to start her and still nothing and now it will not even start w/the bad PFC)

Will report back once I have acquired an "UNMOLESTED!" harness...let this also be a lesson to all...Be very careful with these so called "Single turbo harnesses" lurking around the forums. So far I'm 0 for 2 on them

Derex'7

iTrader: (16)

Okay by chance anbody know what this connector goes to? it loooks like some kind of aftermarket knock sensor but I have left it hanging ever since I had this harness



Hmmmmm...?!?!?!?!?

cewrx7r1

iTrader: (2)

I suggest you just buy a new engine harness and stop troubleshooting that POS!

Derex'7

iTrader: (16)

Yeah I just went ahead and invested in a newer unmolested harness...

Selling this harness for parts or a project

Derex'7

iTrader: (16)

So 1 engine, 3 harnesses (two bad), 3 Apexi Pfc's (only 1 bad), 2 fuel pumps (1 fried), and a host of other misc components She finally f&*cking starts and drives and everything is in sync


Damn is she responsive..

So basically a corrupt pfc + POS stripped harness = Car starts but runs like ****...Mix into that equation either a proper harness or pfc and you get nothing.

Please to all be very leary of these so called "single turbo harnesses and apexi untis" floating around. This has been a very costly lesson and unfortunate experience for me, but my car runs beautifully now and I'm jus ready to move on

arghx

iTrader: (3)

Glad to hear you got it sorted out, and I'm sorry to hear that you had to learn the hard way like the rest of us.