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Bad TPS???

2934 Views 25 Replies 8 Participants Last post by  cheappower82
Well further testing shows that the TPS is cosntatntly putting out 5 volts. I do not understand why but I just assume its broken. At leist I hope. Im hoping thats its not doing that because of some type of constant ground somewhere or something. Im going to try and replace it and if that doesnt work then Ill now I have to chase some damn wires down. Thanks much...

PS- I wonder what this is doing for my fuel trims...consdiering the EFI runs the injectors and timing according to TPS, and the AFM. Although the AFM is functioning fine I wonder if the TPS is making things screwy. If anyone knows of anythign that this might be please chime in. THanks,

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I just got a voltmeter and meausred the black wire from teh back of the connector while it was still hooked up. It showed constant 5 volts, so then I measure the others and got nothing. This was while fluctuating the throttle on all three with the car on and with the car off to make sure...
I dotn have the round one, i have th erectangle one. Mine is a 84 p type Manual ofcourse... thanks
Well this fuggin sucks... Is tehre a way I can convert to a 85 TPS? Anyone =)

Does anyone know where I could get in contact with someone who has an sfc on an pre 85's?
No well you can just ignore the hi and lo. If I did and tried to tune on high it would give me the same corrections all the time and I obvioulsy would want it a little leaner on the lower throttle points...

Id be willing to bet the 85+ TPS have something to do with the knock sensor to. I do not know what to do right now with this, cause Id really like to be able to use the afc. I just do not understand why the sensor would be putting out a constant voltage like that. i tested all 3 wires in all positions and the 2 put out constant 5 volts where the other is prolly a ground of some sort. I still havent changed the TPS cause I figured if it runs fine and there are no CEL's then its prolly just the way it is. Do you think I shoudl bother spending the money to buy another TPS and see if its just mine? Or shoudl I sell the afc-2 and try and get something else to work for fuel adjustment? What else could I use, is there any other way to help tune like the afc can for our cars?

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Well i sont know what you mean about the 3 wire o2...that doesnt have anything to do with it. What I mean is that since the TPS at the ecu shows a constant of 4-6 (anything over 4 will read 100% to the afc) its not fully functional with our cars.

The reason being, is that since the afc has a high and a low setting feature you are normally allowed to control each according to TPS and TPS only. If the afc is always seeing 100% then the only thing we can tune for is high throttle. if you tune anything low throttle it will be disregarded sicne its always 100% and the low throttle maximum NE point is like 49% (signal from the tps) then its impossible.

However I was thinking that since we can screw around with the AFM's, that we could just adjust the afm leaner so it idles and does ok at low throttle, but during high throttle we can adjust the afc and it wil work, because we are always seeing 100% which is ok since the high throttle NE point minimum is like 50 or 60% or something and if it sees 100% it will adjust accordingly. I figure this is ok since Mark said that his idle and everything is ok with just the AFM adjusted as well as a few other MKII guys that dont even have an afc. So the advantage that we will have is we can lean it out a bunch with the AFM and then just ue th eafc to either richen or lean out a few spots where ever as long as its full throttle. So Im not all that upset anymore knowing that I will still be able to control at leist the important (full throttle) side of the tuning....

Im getting real close to finishing up my car. I will probably be done as soon as I get the rest of teh stuff from good ol' Aaron Garney. :evil:
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oh it doesnt affect us. You gotta be using it as a 6 cyl progressive throttle or else the setting wont work. There is only that one that works for us and it doesnt even work for 82-84 :cry:
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