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wierd power


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im wondering what would cause this

 

my loyale is being weird whenever i floor it in any gear other than first i lose power after 3500 rpm unless i bring the throttle back to 60-75%. if i bring the throttle back it will gain resonable amount of power... almoust like full throttle but still less. first is probably too short to tell if its doing it though.

i just replaced the timing belts, plugs, rotor, air filter, pcv valve, fuel filter, oil and filter, i seafoamed it, and its in timing spec

 

also what would cause my odomiter to go up 4 mi every time i go around the block

 

friggin $50 car

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the TPS can be tested in place, and I highly recommend doing so before potentially wasting the time involved in replacing it.

 

not saying that it isn't a likely culprit, but you should test it before replacing it anyhow.. it IS a very expensive unit to buy new, and if you replace it with a junkyard unit you should test it before installing, as well.

 

Wasn't there something that could be ground off of the bracket that made replacing the TPS possible without removing all that crap???

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when you test it does the problem look like a little hesitation or will it outright not rev

 

after a tad of "normal" hesitation the engine picks up and will rev in neutral and what seems to feel like first also

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The symptoms you are describing DO match what a bad TPS can do.. but other things can "feel" the same way.

 

To test the TPS, you need to use a multimeter. If you don't know what that is, say so and I can explain further, but for the time being I will assume you know what one is, and how to use it. All you need to do is unplug the TPS, which is a small black sensor on the right side of your throttle body (as you are looking at the engine) There are two terminals on the TPS to measure the resistance between, I forget exactly which ones. You clip your multimeter leads onto the two terminals, and check to make sure that resistance gradually increases as you gradually press down on the gas pedal, with no jerks or skips.

 

The TPS is basically like a volume knob attached to the throttle plate.. as you open the throttle more (push the gas pedal) it "turns the volume up" slowly and evenly.. well, as slowly and evenly as you apply the gas pedal :burnout: Anyhow, to get back to my metaphor, if the TPS is like a volume knob, then a BAD TPS is like a volume knob on a stereo that doesn't work right, and gets all crackly when you change the volume.. you ever experience that?

 

The "volume" signal that the TPS generates is fed into the computer, and it uses that to figure out how much fuel to feed the engine. So, bad spots in the TPS translate to your engine failing to get fuel when the pedal is at certain positions. However, the EXACT same problem can also result from a perfectly good TPS, and bad wiring for the TPS. A good way to "test" the wiring is to flex the entire length of it, one small section at a time, while the engine is running. If the engine stumbles, or surges, and that coincides with flexing a section of wire, then you know you have found a "bad spot."

 

I sent you a private message asking for your email address, so i could email you a .pdf file with the exact TPS test procedure from the factory service manual. VERY helpful in diagnosing this problem, and you might imagine.

If you have any more questions, fire away.. I'm kinda practicing for an eventual write-up to just link to any time this question comes up :)

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  • 4 weeks later...

thanks for all of the ideas... i figured it out. it ended up being my drivers side bank of my ea 82 that appeared in time at every other angle was a tooth off

oh well that will learn me not to triple check everything

 

after i lost $12 in tools trying to get the ac compressor out

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