afc reads 16% throttle @ idle
 

isnt that wierd, my throttle cables are fine, tried pushing the pedal up, but it reads 16% throttle when your foot is off the gas.

Its always had an idle problem, but it still hold a throttle, Im 100% sure the cables are not bound and its fine, must be a computer misread???

Sound like your TPS isn't set correctly.

You can adjust your tps quite easily with your safc. Put your safc on sensor check and adjust your tps when the engine is hot (does not have to be running). Adjust it to 1v or as close as you can. The closer the better.

If you can somehow prop up the lever on your waterwax solenoid then you can adjust your tps when the car is cold. This method is actually a lot easier and a lot more accurate do to the slow cooling of a hot engine giving you an improper reading. This is very good if you have a turbo and you have to remove the intercooler, it buys you infinite time to make the adjustment.

Make sure the throttle is clean and free (oiled) or else you will get an erronious reading.


Make sure your safc is set for the up arrow for the tps setting.

It would take well over an hour for the engine to cool enough that the thermowax has an effect. It takes less than 10 minutes to remove the intercooler, set the TPS and reinstall the intercooler...

fa sho'!!!!!!!!!!!

TPS adjustment
 

Can be done with a stock tmic. Using back probes and a long screwdriver. Just remove the hold down bolts for the tmic and you have enough room.

sweet
 

good news. I was able to adjust the tps to almost 1v.

1.05 to be exact :).. now, my check engine light doesn't come on anymore, it read 0% throttle and if you rev it high and let it drop , its smooth, before it would pop a lot!!!!!

Bad news, I bought a frieking nother tps for 60 dollars and it wasn't the problem, I hooked up my old tps and it read 1v also, I just never knew the afc could read the voltage.

......Another note...Now that its fixed, my idle is really wierd, it will idle at 750 rpms, then after several seconds, it will drop to 700, 650, 600, 550, then it will die,

any thoughts?? it hold a perfect idle for 5 seconds, then it slowly drops and drops, and drops, then dies......thats with the tps in spec???

what do I need to check for that?

When this idle is dropping from 750 down to zip and dying, have you observed the output of the tps to see if the one volt is changing at the same time? If so maybe you need to set your fast idle cam etc. Just a thought. Sort of sounds like the cam is slowly coming off the roller. But if you've done the throttle body modification, then disregard all the above words. EDIT: Nah. If it is indeed caused by the fast idle cam coming off the roller, then its a matter of setting your idle right, not messing with the fast idle cam.. If you see the voltage droping as the idle goes down, that is indeed the fast idle cam and roller interacting. It also means the tps needs to be set after the cam comes off the roller. Not as its set now.

Quick question: Can you use the s-afc to adjust a dual plunger tps? (89+ ones) CJ

yes
 

it just worked on mine tonight!!!> my car was running like shit, I didn't realize you could read the voltage off the afc. I tuned my 89 dual tps as close to 1v as possible, my car runs TONS better.