Help with the porscharu: Grassroots Motorsports forum: Grassroots Motorsports Magazine

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Dec. 19, 2010 10:49 p.m. snipes Reader

Ok I posted this over at NASIOC, but I wanted to give some of you smart GRM guys a crack at it.

"Well I am having a hard time getting the car to run correctly. Its a 1979 porsche 911 with a 1996 UK sourced WRX motor. I am down to one CODE 23. So I did a continuity test from the meter plug to the ECU and that checked out fine. Then I bought 2 MAF at the pull-a-part and tried both of them. I reset the ECU each time I swapped meters and I am still getting code 23. The car runs RICH and rough. It is a little better when it warms up, but still not great".

More background: -Cleaned all the MAFs with contact cleaner -New plugs, fuel filters, after market fuel pump -Sock fuel pressure regulator
Dec. 20, 2010 8:07 a.m. Dr. Hess SuperDork

I take it a code 23 a MAF. Check all the connections on the MAF to wherever they are supposed to go. Do you have a schematic of the system? If I recall, one lead should be switched power, one should be ground, and some signal stuff. Check all that. Check the voltage on the signal out line. Compare with what the book sez should be there.
Dec. 20, 2010 8:10 a.m. Giant Purple Snorklewacker SuperDork

Make sure you have good grounds. If you have different potential at the ECU and the sensors your signals will be all fubar.
Dec. 20, 2010 8:12 a.m. John Brown SuperDork

Are the North American MAF correct for the UK engine?
Isn't there a fuel difference between Europe and NA? Have you tried running it on regular unleaded fuel?
Check your grounds again.
Is there a blockage in air flow tract? Mouse nest? Poor routing?
Dec. 20, 2010 11:11 a.m. snipes Reader

Thanks for the help guys. The NA and turbo cars use the same MAF. So that makes things a little easier. The guys on NASIC posted this

So I will do these steps and let you guys know what I find. I really need a factor service manual for the motor.
Dec. 20, 2010 11:32 a.m. snipes Reader

The other good news is the porsche has been repositioned for basement removal. It feels good to have the car pulled out of the corner, after a solid year and a half of confinement. The wheels are on and the tires are full of air. I will not be putting this thing back on jack-stands with out driving it first! I hope.
Dec. 20, 2010 7:28 p.m. Winston Reader

I think I see your problem...
-Sock fuel pressure regulator