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markbudgen
06-11-2004, 11:30 AM
Guys,

I have a Porsche 993 driver with a supercharger on it. Not pushing anywhere near as much power as some but as I've used this site for information so many times I have a question that I hope someone might be able to help me out on. Car runs fine in warm weather O2s around 800 with a 50:50 mix of methanol/distilled water injection based on a souped up 1S system. I have a pre-race pump priming pump and a 2 stage injection system. When it gets cooler say below 10C the AFR soars off the scale (weak). I'm not sure if it is a side effect of the methanol/water injection and to be expected or its a real issue. Car runs fine but the AFR tells me something is amiss. Tried lots of things, temperature sensor, fuel pressure, all spot on. So i'm left with this being a side effect of the methanol injection or the Air flow meter. So my question really is would injecting alcohol on a cold day cause the O2 reading to read way to weak when in fact it is ok?

Many thanks for any help you can be, Mark.

PuntoRex
07-11-2004, 02:37 AM
Have you seen this (http://www.aquamist.co.uk/phpBB2/viewtopic.php?t=193)?

Maybe something in common.

Good luck.

markbudgen
07-11-2004, 07:25 PM
Thanks Puntorex,

it just could be. I'll try the car with just distilled water and see if I get a change in its behavour.

I'll post if I see a change. Now got to use the methanol up over the next week or so. :-) before I can refill with distilled water. So it could be a week or so before I know there has been a change.

Cheers, Mark.