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What will a bad tps do?

Old 07-28-2008, 08:18 AM
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What will a bad tps do?

I'm getting the 21 or 24 code, but the car runs ok. This is on an E4ME carb. I'm getting both codes but one is becuase my speedo isn't working.
I don't really want to replace the the TPS, I'm just wondering what kind of damage or problems this sensor malfunctioning is going to cause me.

Last edited by RazorN8; 07-28-2008 at 02:18 PM.
Old 07-31-2008, 12:53 PM
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Re: What will a bad tps do?

Mine was reading 5volts all the time when it went bad, had an off-idle bogging problem, and the torque converter locked up too soon. Bad gas mileage also. Not sure if it'll damage anything because I took care of it in short order, but sometimes if your mixture is too rich you'll smell fuel in the crankcase, which is never good for the internals.
Old 08-02-2008, 07:32 AM
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Re: What will a bad tps do?

when i first bought my car i also got those codes. the issue i had is that the car was extremely slow to respond, very little power in the low rpm range, and no 0 to anything power. it was this way for almost five months and i never saw any change in the performance for better or worse, after changing the tps i immediately received what seemed like an insane amount of power. the car had horrible gas milage as well during the bad tps months. i would reccomend changing it if possible i think i picked one up at auto zone for fifty bucks.
Old 08-02-2008, 08:46 AM
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Re: What will a bad tps do?

The TPS is not that hard to check. I don't have the actual specs, but I can get them. With a volt meter you just look for a smooth resistance change as the TPS turns. If you find any dead spots or sudden spikes, its bad. I can get you more info if you want it. If its bad you will get syptoms like dvardaman85 described or you might find a bad spot at a particular speed. Car runs rough only at a particular point in acceleration.
Old 07-16-2009, 07:57 PM
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Re: What will a bad tps do?

I have a similar issue. My TPS is 1.58v at idle and goes up to 4.2v. The car has no low end power, even after head and cam change. I guess I swap the TPS, but do not have any codes.

Did you replace the airhorn gasket when you did it? Or is all you need the new sensor and just reuse everything else?
Old 07-16-2009, 10:25 PM
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Re: What will a bad tps do?

the specs are in the tech section. a bad tps sensor can cause boggong and erratic throttle. it needs to be a smoooth resistance from close to fully open. and there is a max and min reading.
Old 07-17-2009, 03:24 PM
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Originally Posted by dstss
The TPS is not that hard to check. ... With a volt meter you just look for a smooth resistance change as the TPS turns.
Not to nit-pick, but the carb TPS is a plunger built into the carb.

If you said, "...smooth resistance change as the throttle is turned," that would be a little more accurate.

Personally, I've never had one go bad, so I don't know what would happen. I was fooling around once and disconnected it to see what wouldn't work, and as I recall all that happened was the SES light came on. Seemed to run fine, even the cruise control and TCC lock-up worked, but it wasn't an extensive "test".
Old 07-29-2009, 07:26 AM
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Re: What will a bad tps do?

Well I finally located an airhorn gasket for $4 off a carb builder (Avanti--who are great!). I installed the new TPS late last night. One question: was i supposed to do something iwth the adjusting screw during re-installation of the airhorn? Everything fit back together and the little piston is on top of the plunger. Im just concerned that I didnt do something right with the adjusting screw. Very anxious to get this thing back on the car and see if this made a difference!
Old 07-29-2009, 08:08 AM
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Re: What will a bad tps do?

when i replaced my tps i just replaced the tps assembly and thats all no gaskets no extra hardware. you factory q-jet should have adjustments already performed on it if you have made adjustments in the past then it is possible that you may need to tune it a bit but just with reinstalling the new tps (if that was in fact the problem) you should be able to see a world of difference. have you gotten the car back up and runnign again
Old 07-29-2009, 08:15 AM
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Re: What will a bad tps do?

No I have not. I am also trying to get information on re-sealing the well plugs. They may be leaking, or at least they have gas on them...

I need to figure out where exactly to spread the JB weld (I guess Im kinda dumb when it comes to Qjets.)
Old 07-29-2009, 08:33 PM
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Re: What will a bad tps do?

Started the car up with after reinstalling and calibrating the new TPS (.54 at idle and 4.2v WOT). Now the car will not rev smoothly. It stumbles between 1500 and 3000 rpms. The car cannot be driven, as it will stall with ANY amount of throttle over idle when in drive!!!! I swear I am going to lose it with this thing (cash for clunkers time???) Could this be the leaking well plugs, and the former TPS sensor at idle had 1.58v compensating for it?
Old 07-29-2009, 11:17 PM
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Originally Posted by tommy z-28
(cash for clunkers time???)
Sorry, doesn't qualify.
Old 07-30-2009, 07:19 AM
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Re: What will a bad tps do?

Why doesnt it qualify? It is rated at 17 mpg blended on the gov's site?

Anyways, I really need to figure out this lean condition off idle that is causing it to stall.

Someone told me to adjust the TPS one turn counter clockwise and see if it corrects the condition (disregarding the voltage settings suggested in the manual).
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