R34 Maf Voltage Issue

[paulr33]

yeah that is completely wrong

it should never be like that

if you unplug the AFM sensor completely does it do the same thing?

if you unplug the TPS sensor completely does it do the same thing?

when you unplug the sensor on a car thats running a PFC the sensor name will go in black highlight under ETC, SENSOR SW CHECK and the engine light will come on

this might give away which of the sensors wires is mangled up

if you unplug the AFM at the sensor and it still shows a value you know the AFM wires are f**ked

if you unplug the TPS sensor and the values go away you know the TPS is at least wired in properly, but could still be bridged at the loom etc

[debusan]

yeah that is completely wrong

it should never be like that

if you unplug the AFM sensor completely does it do the same thing?

if you unplug the TPS sensor completely does it do the same thing?

when you unplug the sensor on a car thats running a PFC the sensor name will go in black highlight under ETC, SENSOR SW CHECK and the engine light will come on

this might give away which of the sensors wires is mangled up

if you unplug the AFM at the sensor and it still shows a value you know the AFM wires are f**ked

if you unplug the TPS sensor and the values go away you know the TPS is at least wired in properly, but could still be bridged at the loom etc

Thanks for the info I will try that later. I do know that I can completely have the MAF disconnected and the same voltage phenomenon occurs. However if the MAF is not plugged in the car won't start and run its a strange scene to be sure. It seems the MAF is still giving a reading but it is also reading from the TPS as well hence the weird voltage fun. Since I have wired the MAF directly into the PFC with my own wire that leads me to believe that the PFC is the culprit however I will do some further troubleshooting with your advice such as unplugging TPS etc. I will keep you posted on what I find.

Edited January 23, 2013 by debusan

[debusan]

A small update If I disconnect the TPS harness under the hood the MAF reads as normal but that really doesn't help at all.

[Adriano]

have you checked the earths?

[Livinlahtimmah]

Any resolution to this? 

I am having the exact same issue on my 34 Gtt with power fc. 

Car was warming up and died.

will crank twice, fire, then die a second later. 

Motor has 160-165 across all 6. 

New gs342 Walbro's are running fine

Unplugged afm, still reads same value as tps.

unplugged tps, no value registers 

Tomei plug will only go on 1 way, all soldered joints good.

Loom not melted/ no rub throughs/ all behind heat shield. 

Ecu connector looks ok. No pinched wires, terminals seated in connector. Nothing stands out, 

Found a shit ground in engine bay near turbo, Ran a test piece to ground motor to strut tower. Same result.

z32 and Tomei plug is 500km old

tune by Jez on power fc is only 500km old.

really hoping I don't have to fork out for a new Ecu.

[Livinlahtimmah]

For anyone with an issue like this in future. Been talking to fc hako re a possible repair to the ecu, he suggested I pop open the afm to check for dry joints in the pins at main connector. Joints were good but four this, brand new afm from justjap also.

1 circuit not soldered and the Blob of solder intended for bare joint bridging 2 circuits, unpicked with finger nail, no penetration to solder on other circuits but enough to bridge them.
First thoughts would be it should have fizzed at first power up before I even hit the dyno, but it's possible the blob dis lodged and rolled to its final spot.
New z32 tomoz, will power up and see if ecu will work per normal

[Livinlahtimmah]

And the app won't let me upload photo...