Inaccurate TPS signal
#1
Inaccurate TPS signal
Something is wrong with my TPS signal. When it should be at 0%, it will sometimes show anywhere from 2% to 10%. I replaced the TPS and it still does it. With the throttle closed, it reads .62 volts on HP Tuners.
Last night on the way home, with the throttle closed, it was always showing 7%. I pulled over, turn the truck off and restarted it. Now it showed 4%. I drove some more and stopped to get gas. Now when I restarted it, it showed 0% like it is supposed to.
Sometimes when it is at 0% and I'm idling, it will suddenly jump to 5% or whatever and stay there when I don't even touch the throttle.
WTF could be causing this? The voltage reads correct. There are 3 wires going to the TPS. A 5 volt (I think), a signal, and a ground. Which one would cause this? I have a voltmeter if you guys can tell me how to test a ground wire with it.
It is really annoying because it makes me idle 1000 RPM and surge all the time.
Last night on the way home, with the throttle closed, it was always showing 7%. I pulled over, turn the truck off and restarted it. Now it showed 4%. I drove some more and stopped to get gas. Now when I restarted it, it showed 0% like it is supposed to.
Sometimes when it is at 0% and I'm idling, it will suddenly jump to 5% or whatever and stay there when I don't even touch the throttle.
WTF could be causing this? The voltage reads correct. There are 3 wires going to the TPS. A 5 volt (I think), a signal, and a ground. Which one would cause this? I have a voltmeter if you guys can tell me how to test a ground wire with it.
It is really annoying because it makes me idle 1000 RPM and surge all the time.
#3
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I am having the same issue on my 2000 Silvy as well. Ocassionally the throttle position sensor will read 13% without pressing the throttle and idles around 1000rpm's and can raise the shift points. Then it can be re-started and go away for a time and come back.
Someone suggested cleaning the MAF, which oddly enough seemed to help for about a week or two then the problem started intermittently again, so I have a new TPS ready to go in when the weather clears and I feel like pulling the alternator to get at it.
I'm also gonna look at the Air Filter... It's a Fram Airhog pre-oiled from the factory. I know there have been problems with people over oiling and the MAF, this one is stock but needs to be changed anyway. I'll throw a paper one in and clean the MAF again?
Someone suggested cleaning the MAF, which oddly enough seemed to help for about a week or two then the problem started intermittently again, so I have a new TPS ready to go in when the weather clears and I feel like pulling the alternator to get at it.
I'm also gonna look at the Air Filter... It's a Fram Airhog pre-oiled from the factory. I know there have been problems with people over oiling and the MAF, this one is stock but needs to be changed anyway. I'll throw a paper one in and clean the MAF again?
#6
My front bearing was completely gone, so I replaced it in the 25* cold. After that, the truck was surging again, so I got pissed and just untied and examined the lengthened (for the Radix) TB wiring from the TB to the original cut in the engine harness.
It turns out the wiring was touching the alternator and it had melted a small area through the wire loom and was probably sending electrical interference through the wires. I repaired the loom and routed the wiring over the snout (until it is warm enough to repair properly) and it has idled perfect for 3 days!
It turns out the wiring was touching the alternator and it had melted a small area through the wire loom and was probably sending electrical interference through the wires. I repaired the loom and routed the wiring over the snout (until it is warm enough to repair properly) and it has idled perfect for 3 days!