I fiannaly got one and installed it today!!!!!!!!! So does our tps not really read the whole stroke of the throttle? It seems that the throttle is no longer in contact with the tps after about 1/3 throttle, leaving my SAFC reading 100% long before the throttle it all the way open. I guess this is normal??? DO S4s Have knock sensors? The wire diagram shows there being one but my ecu has no wire in that posistion. Please help me out I'm so excited to have it installed I just want to make sure everything is right

 

Only TII have knock sensors

 

You are correct about the TPS and theonlygreat is correct about the knock sensor.

 

OK so is there any adverse affect of having the safc think i'm at 100% when i'm not?

 

bump

 

did u set it up to be runnin like a 4 cylinder, and flap for the sensor option? make sure u reset it after u install

 

Some people think the boost/pressure sensor is a better source than the tps.

Then again, I wonder about that. Here's why. I know that almost all the time while driving on the hwy that the tps is NOT at its full travel, I've watched the voltage output of the tps at close to seventy mph while cruising down the hwy. It ain't at full voltage.

The tps is at its full range when the secondary plates just start to crack open. Go look for your self sometime.

That said, I do have a turbo and I did use the boost/pressure sensor in lieu of the tps with the SAFC that I recently bought.

I'm going to buy another SAFC and put it on my 86 non turbo and use the tps instead. I'll let you know what I think when I do.

Oh! If using a wideband, be sure to disconnect the 02 sensor while tuning. The ECU will try it's damn hardest to keep the afr at 14.7 if the 02 sensor is connected up and your tps is still not maxed out. I had taken fuel out so to speak in the Low Throttle range and was seeing the fourteen something afr, then I got a touch smarter and removed the 02 sensor and saw readings in the sixteen something range. Not good. So I tuned (if you could call it that), with the 02 disconnected...then reconnected the 02 sensor when through. O2 sensor is not used by the ECU during hard throttle, but you probably knew that already.

By the way, when you go to SENSORs on your safc, the tps should read one volt at idle. If not, adjust the tps screw til you get one volt at idle. On the high end it'll read under five volts, most likely around 4.65. That high voltage, whatever it is on your car is when the tps has reached its full travel. Go for a drive on the hwy and see if you are not still a touch under that voltage when driving around seventy in fifth.

I use a wideband from 0Z on mine. I'm not sure how you make adjustments without one. Last time I looked a non turbo series four was way rich around five grand and needed less fuel. Just memory there.

 

By the way, disconnect the 02 sensor when tuning in the Low Throttle Range. You can take a ton of fuel out but the afr will still show 14.8 if the 02 sensor is still connected up. The ECU will work it's butt off trying to maintain 14.7afr during low throttle. I disconnected the 02 sensor after I had made corrections and to my dismay I saw afr of 16/17. Not good. So I made my corrections again with it disconnected THEN reconnected the 02 sensor.

 

Since I'm getting an S-AFC soon, what all is involved in the install? Are there connectors or anything I'll need? I'm not sure if I'm just getting the unit itself or the instructions or anything so if anyone knows of a thread I've not found in the search that goes over the S-Afc completely PLEASE let me know.

 

It's purely electrical, and easy if you have a bit of electrical experience. You're basically tapping into the ECU's wires. If you're not confident identifying wires and making good electrical connections then get someone else to install it. You don't want to mess up the ECU...

 

Nah, I'll be fine. I had to rewire my whole stereo when I got my car, and have had a few other things. Wired in a switch so I can have the radio on but the antenna down, great for auto carwashes , and some other stuff. I should be fine.....

 

http://www.1300cc.com/howto/how2/safc.htm

The above should help. The instructions that came with the unit are BAD. I for the life of me don't see why the install is written towards the back of the manual.