Code 63 & 31 low voltages

[jimbob]

Hi guys,

My car is struggling to idle...it will start right up, then die unless i hold the revs on.

I pulled the codes and got a 63 (low voltage to the throttle position circuit) and also a code 31 (EVP low voltage)..i tried swapping the voltage regulator, but this has not stopped the problem. I have also checked the alternator, but that is putting out a healthy 14volts....is the code 63 likely to be the throttle position sensor or a problem with the engine management??

Any other ideas anyone?

Thanks.

 

[JoshMcMadMac]

Why are you messing with the alternator and regulator if the codes tell you TPS and EVP? You should adjust the voltage of the TPS, and replace if necessary. Then clear and check codes again. The code 31 may be as simple as cleaning the emissions parts like IAC and EGR.

 

[jimbob]

I tried the voltage regulator first as i read somewhere that its best to replace before trying to find any electrical problems.

How can i adjust the voltage on the TP sensor? i checked the workshop manual and it says it is non adjustable?

 

[JoshMcMadMac]

I tried the voltage regulator first as i read somewhere that its best to replace before trying to find any electrical problems.

How can i adjust the voltage on the TP sensor? i checked the workshop manual and it says it is non adjustable?

Valid point on the voltage regulator...in this particular instance it probably wouldn't relate, but if it's in question it is certainly better to chalk it up to maintenance now. TPS adjustment is here: http://www.lincolnsonline.com/tech/00127.html

 

[jimbob]

I followed the procedure for adjustment, but it made no difference.

What i found is this though: I have a steady 5.10+ volts on the ref wire, even as the engine dies it does not drop below this. With the keyon/engine off, i seem to get 0.9 volts minimum with throttle closed (took a while to get a good connection to the wire) However when i start the engine, this voltage may stay steady, and the engine will run, or, it may drop to 0.7volts and the engine will die. So does this prove anything?

 

[Ricks90billblass]

That sounds like the classic bad TPS sensor symptom.