sure IT CAN, and a great question! the TPS idle switch stuck open or closed, but you must drive it hard for this to trip. will throw a DTC for TPS idle.
sure will. but can be very insensitive,
the TPS has 2 parts, the throttle angle and the idle switch
the ECU never reports angle off (called the TP output by suz) only if shorted ground <0.2v or stuck at over 4v all the time.
the ECU thinks wild readings are all driver caused. as surely it can be... or is asking for unflood mode, all very normal and even starting with right foot at 10% throw no codes.
The TPS idle throws if idle is low, for a very long time, HOT, and fails to see the switch closes.
same with stuck open. it watches RPM and MAP for a long time. and if the readings (long time checked) are incongruity to the switch, bam.
my guess is his mech. set the idle calibration wrong and on the hairy edge. (didnt use the 3 feelers like the book demands) so since on the edge, it fails randomly.
I calibrate mine the torture it to make it fail by blipping the trottle over and over and using the GO /NOGO feelers.
if yous set it late (late open) the TPS ISC idle loop fights your right foot action.
The throttle angle glitch causes the ECU to enter ENRICH mode for every glitch , not a pretty sight that, and no DTC for that.
i never ever mess with that, i use my voltmeter at the moment of the failure, because you cany fix it or find it , if it is not busted.
and trusting the ECU to tell you this is not reliable at all.
after all, its only failing for short time. and the ecu is blind to short time fails, its even blind to intermittant TP angle glitches do to , it THINKS DRIVER is driving funny./
the ECU only finds, dead opens and dead shorts. and not much else, unless very luckly.
id does not find weak map sensors
or other weakness , except that pesky 400s EGR test.
to find a bad TPS, angle output
use a voltmeter on the TP pin,
it must be totally linear with no drop outs, moving it. if it clitches its bad.
on a real scope the glitches are easy to see.
per here
![[Image: glitch.jpg]](http://www.fixkick.com/sensors/TPS/glitch.jpg)
for sure its not his idle switch , driving fast.
just the TP pin per above.
The ecu looks at fast changes, on the TP, if it sees them it activates ENRICH mode. fast. in fact so fast , it beats the pure air slug at the intake head valves.
that is what the TP does, it uses the speed of light (1/2 joking) to beat that air slug (quote, jeff hartman)
with a dead, TP the car bogs with a fast right foot
if the TPS fails, an glitches the ECU thinks (wrongly) that you did move your right foot fast, but in fact you did not.
see?
on carb cars this was a shot fuel sparyed into the venturi.
on EFI cars, its a fast ENRICH mode. for the same reason, exactly.
it stops the bog, drive car car with a dead pump there, accel pump.and see that car bog fast.
the carbon wears out at your favorite speed, if 55 mph is it, bam that wears out.
in the city its the off idle spot. goes bad.
