Re: Problem adjusting TPS References: <200003071629.LAA02121@www.theautochannel.com>

[Roger Brown <rogerb@xxxxxxxxxxxxxxxxxx>]

Menko Johnson wrote:
> I'm having some trouble adjusting my TPS and needed some input.  My 87
> 4Runner has been idling poorly, bad gas mileage and hesitating.  I pulled
> the following codes: 2,5,10.  It was suggested that I adjust the throttle
> position sensor.  Here's my problem:
>
> I was able to adjust sensor so that I get the correct resistance for the
> first 3 tests listed in the manual
>
> throttle closed
> .57mm (I measured at .56)
> .85mm (measured at .86)
>
> But when I do the VTA-E2 and the Vcc-E2 tests with the throtle wide open, I
> have no resistance at all.  If I close the throttle and open it slowly, I
> have resistance that climbs to about 1.9 KOhms when the throttle is 1/4
> open and then it cuts out to 1.  I tried to adjust the full range of the
> sensor and still was unable to get a reading with full open throttle.
>
> Can anyone tell me what this means?  This TPS is only about 5 months
> old.  Should I attempt to adjust the stop screw to change the position of
> the throttle?
>
> Any help is much appreciated.
>
> Ps- mail me direct since I'm in digest mode

The Vcc-E2 measruement shouldn't vary with throttle position, it *should* be a
constant resistance.  If you are getting a variation/open in it, I suspect
there must be a burned out spot in one of the internal circuit traces.