kevincnc

Putting in the Vitesse Stealth MAF, I have the MAF and chip/board installed. The new injectors and resistors are not installed yet. When I try to start the car, it immediately dies when it gets up to idle speed. I got the Vitesse pre-made plug together wiriing adapter, and I'm sure the MAF is getting power, what could be wrong?

Ski

Do you have the MAF power wire hooked into the diagnostic port, the one with 12v switched on?

kevincnc

Not to the diagnostic port, but it's getting 12V. I've been advised that it's probably because I didn't put the larger injectors in yet, stand by...

TT

Put the injectors in and try again.

fast951

Kevin, I emailed you already. The chip/board is programmed to run with the 72# injectors at 3bar FPR.
Running with the stock injectors will be VERY lean.

special tool

Duuuuuuuuuuuuuuuuuuuuuuuuuuuude

kevincnc

Well I never claimed to know what I'm doing- injectors are in and it still doesn't work. John called me to help but now he's unavailable for the day.

Can anyone confirm the wiring to the MAF connector for me?

As viewed in the picture from left to right I get with a meter:

1) GND- I assure this is for the air temp sensor
2) Continuity to pin 7 at the DME
3) GND
4) GND
5) 12V
6) 4.3V

I tried flipping down #1&2 on the chip/board. Also played with the FQS. It starts and then dies immediately. I didn't mess w/the TPS and I can hear the switch click when it's closed. All connections are tight and I was very careful with the chip not to zap it with static.

What could be wrong?

theedge

Where is it getting power from? Have you verified that it has power in both key positions (start and run)? Youll need someone to hold the key in the start position for you. Look behind the brake booster, there will be a white or clear 2 pin plug, a thin blue wire and a fat red wire out each side. Unplug that, and the starter wont spin. Dont unplug the DME relay, in case youre getting power from it.

Ski

Where are you getting the 12V supply from? This start/die, for an MAF, is classic case of not getting a full 12V to the MAF sensor - well, in my limited MAF installations.

kevincnc

I'm getting 12V from the stereo power wire, the same source that my EBC is connected to. I can see the lights on the EBC light up with the key on, and also while cranking, and after letting go when the engine starts momentarily. I'm pretty sure its getting power.

Although I got the pre-made pigtail harness, I'd like to confirm that it isn't wired wrong internally (sorry for questioning your harness John, but everyone makes a mistake once in a while. )

Ski

Run the positive wire over to the battery and see if the car starts. The MAF needs FULL 12.1-3 volts to function properly - it needs to be by itself. Just a quick connection to see if that corrects the problem.

I get 12v from the diagnostic port, 12v switched, thick red wire in the pic

kevincnc

Okay I tried that, same results. It starts very quickly, idles smooth for about a second, then dies.

Jake951

That's a sign of no air flow signal getting to the DME. Check with a voltmeter to see if you have a signal on the green/red wire to DME pin #7 when you start the car. If there's nothing (0 volts) then you have either a wiring problem or a non-functioning MAF.

kevincnc

The color at my MAF connector is white/grey for the second pin from the left on the connector shown above. I get continuity from that pin to pin 7 at the DME. The green/red wire is 12 volts, it's the second pin from the right. I think you're talking about the green/red wire on the stock wiring harness though, and that one definately goes to pin 7 of the DME.

As soon as I turn the key to on, I see voltage spike up a copuple of volts that quickly bleeds back down to nothing. Then when I try to start it, it goes up to about .1 volt. As soon as it starts that voltage goes down to 0 and it dies.

Is that a bad sensor, or is it possible that the 2nd pin fron the left and second pin fron the right are reversed on my pigtail harness?

kevincnc

I just saw a picture of another Vitesse MAF, and it looks like the 12V and signal wires are correct.