Two days ago, the idle rpm and the oil pressure during a cold start began to get suspiciously high. The rpm would be 1,200 to 1,500 and the oil pressure would be about 50-55 until the car warmed up and then idle rpm would go down to the normal 500ish and the oil would go down to the normal 30-45. During a warm start I did not have any problems w/ the idle or the oil pressure.
Last night the service engine soon light came on and after I stopped and turned the car off the light did not come back on even after driving for about 2 hrs. I pulled the code with the engine off this morning I got:

13, (1 flash, pause, 3 flashes), Oxygen sensor circuit, “Check for sticking or misadjusted throttle position sensor. Check the wiring and connectors from the oxygen sensor circuit. Replace Oxygen sensor.”

The description that made the most sense to me was the misadjusted throttle position sensor (I really do not know that much about this sensor), so I checked the Chilton’s manual and it had directions on how to check the voltage between the C and B connector on the throttle position sensor. I connected the jumper wires and measured the voltage between the B and C and I got 4.56 volts. The Chilton’s manual said that the voltage should read 0.45 to 0.65. The volt meter is reading correctly (tested it), should I go ahead and adjust this, or the problem something else? Also, when jumping the TPS does the engine need to be cold (it was warm when I tested it)?

 

if it's overvolting that much, you may have lost the ground to that sensor, as well as any other sensor that that ground is connected to.

you may want to check it again though, I'm not trying to insult you, but there's always a possibility that you may have set the voltmeter/multimeter wrong, and it doesn't take but 5 seconds to double check.

check your chilton manual about checking the ground wire for the tps at both the tps end and the ecm, if you're not getting a reading from either of them, it's been cut somewhere, or otherwise damaged.

if your ground isn't lost, again I repeat, double check your reading, then from there you may want to simply buy another tps, they're like 15 bucks I believe, not all that much.

there IS always the possibility that it's not your tps though, more often if you get a code 13 it is actually the oxygen sensor, you may want to run the same tests for that, it could be bad...especially if it's never been replaced.

I just want to mention 2 things real quick:

1. don't run out and buy new parts at the drop of a hat, many times on these cars it's a simple fix, even with their age, many of the sensors on these cars are quite durable, and if you noticed by reading the code, it'll give you multiple possibilies for the same problem, so may go out and replace a part that wasn't bad in the first place(I say this because I probably spent 150 bucks on parts that weren't bad the first year I bought the car).

2. don't bother worrying about your oil pressure too much, if your car is idling higher, your oil pressure will often be higher, that's just how these things work. the only thing you really want to worry about with the oil pressure gauge is if it goes below 20, then you either are very low on oil or very badly need an oil change.

 

I was using the voltmeter correctly, and it is not off by a multiple of 10. The chilton's manual said that the volatge at the TPS outputs is adjusted by unscrewing the TPS and turning it until the voltage is in the range of .45-.65 volts. I was asking if I should go ahead and do this, or if there is something else that I should do. I will check the ground tommorrow, and thanks for the advice about parts (I too have learned that the hard way).

 

Here is a link that will help with adjusting the TPS.
Tech Articles - Adjusting Your TPS

 

hey man I had to mention it, the info you gave me looked a little suspicious .

 

Hey, no offense taken. I hope the post above didn't sound angry.

 

I have a question about the article. I almost have the same reading as the person who wrote the article, but the only problem that he said his original voltage reading was "4.39VDC" and then at the end of the article he said that his voltage was "...0.100VDC off". If he was looking for a range of (0.540VDC +/- 0.075VDC) wouldn't he have been almost 3.8 VDC off?