Rich at idle, lean at WOT

R

Ralf

New member
I installed an Innovate air fuel gauge to monitor my fuel ratio and I had it set to 13.5 at idle and was expecting it to be that way at WOT but I get readings in the high 17 range. I bought the motor from another racer and everything was set up to be plug and play. It was set up to run without an O2 sensor, throttle switches, or any vacume lines. All the ports on the throttle body are plugged as are the extras on the intake boot. Any ideas on why it would lean out?
One other thing that seems to be an issue is I'm not getting any ignition advance. The seller told me that the max I should be seeing is 34 degrees. It stays at 8 degrees.
If anybody has any ideas, that would be great. Guesses welcome too. :)
Thanks
 
Is this a CIS or CIS-E car? Stock VW stuff goes lean at high rpm. Adding a potentiometer in line with the coolant temp sensor will let you add fuel easily. Set it up with a bypass switch, manual or a relay triggered by full throttle switch, so it is not overly rich at idle/paddock speed.

No timing advance is fine. That means the knock sensor is not meessing with your timing. Set it at 31-33 and leave it there.
 
Originally it was a CIS-E car but the motor that was sent to me was set up without throttle switches or oxygen sensor. Everything else was attached including fuel distributer and all accessories. One thing I haven't installed yet is an included Autotech module. The instructions say to tap into the full throttle switch but he had it set up without any throttle switches. He had a dash switch but stated he couldn't tell the difference with it on or off. So that's why I haven't installed it.
He also told me that he set timing to 34 degrees prior to shipping but I couldn't start the car with it set that way, so I reset timing and it started right up.
Could it also be low fuel pressure? I measured pressure at 70 psi but I wonder if maybe the fuel filter could be restricting flow. Its fairly new so wouldn't think it would be clogged already but may change it anyways.
By the way, this was Tim Pitts' old stuff, which was David Boles' old car. So I'm confident that the set up worked great in their car. I just need to get it to work in mine. :-}
Thanks
 
I run mine in the low 30s fixed timing and it starts fine.

The Autotech power modules do occasionally fail. The simple resistor/potentiometer in line with the CTS works as well, but is more simple/reliable. You can absolutely feel it if you switch it on or off.
 
Thanks Chris.
Any links that show wiring diagram and parts needed?
And do you think I should install the throttle switches?
 
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There are some diagrams out there, I just don't know the links to them. Techtonics also makes one, that plugs in to the throttle switches for actuation.

I have seen the switches and the brackets for the throttle switches fail, which kills your enrichment and endangers the engine. I finally ditched them before I went to IT Fest a few years ago and just used a dash mounted switch. I found that once up to speed I could just leave it on rich all the time. It does make it too rich at low rpm though, so some a throttle acutated switch that acts at 2/3 - 3/4 throttle is nice.
 
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