delbert brecht wrote:
> jim beam4/8/08 23:04LPCdnZ0E3bHMr2HanZ2dnUVZ_vDinZ2d@[EMAIL PROTECTED]
>
>> SHRED wrote:
>>> 2002 CR-V
>>> 78233 miles
>>> California
>>>
>>> Throttle position sensor went out so the whole throttle body needed
>>> replacement. They can't replace just the sensor.
>>> Total cost: $1000.00.
>>>
>>> American Honda just called and are going to "review" for possible
>>> "goodwill" coverage. The representative didn't sound to encouraging.
>>>
>>> I have the TSB 04-008 which admits to a defective part.
>>> http://www.in.honda.com/Rjanisis/pubs/SB/A04-008.PDF
>>>
>>> This is so frustrating.
>>> I have owned, and my family has owned, Honda for decades. 2 of our 3
>>> vehicles are Honda.
>>>
>>> This thousand dollar bill is souring me to Honda big time.
>>> It would be a shame for Honda to lose me over this.
>>>
>>> Any advice here?
>>>
>>>
>>> ---
>> 1. don't pay attention to trolls.
>> 2. shop around. the part costs $571 from hondaautomotiveparts.com.
you
>> could replace it yourself.
>> 3. shop around some more. afaict, honda use a limited number of tps
>> designs, and it's easy enough to get another one from a junk yard.
>>
>> if you find one and fit it, be aware that the reason honda say to
>> replace the whole thing is sensor calibration. but that shouldn't be
>> too hard to do yourself. here's how to do it: take a small [fresh]
>> battery, say 1.5v or 3v, and connect it so the battery is between the
>> two outer connectors on the tps output - they connect to the resistor
>> track. then measure precisely the voltage between the middle one
>> relative to both the outers. the sum of the two should be exactly the
>> battery voltage when connected. it should be roughly 0.15v relative to
>> zero if the battery is 1.5v. again, measure this precisely with a dvm.
>> now, after fitting the "new" [or repaired, which is also possible in
>> my experience] sensor, position the sensor so that it now replicates
the
>> exact same voltages with the throttle in the same position.
>>
>> now you have a calibrated tps and you can drive again! usually, the
>> sensors fail at a point on the track where the throttle most commonly
>> sits when driving, but it's ok at the idle position so you can do this
>> measure/calibrate procedure.
>>
>> oh, and honda usually use shear head bolts to hold the tps on. those
>> will unscrew if you carefully use a chisel, or even a reverse helix
drill.
> Jim
>
> I understood most of what you said about calibrating the TP sensor but
got
> just a little fuzzy on this sentence.
>
>> it should be roughly 0.15v relative to zero if the battery is 1.5v.
>
> Did you mean 0.15 volts? Or was it a typo?
no, zero point one five. or approx 1/10th of the total voltage.
> If you could explain it again it
> would be very helpful.
just like a potentiometer used in electronics, the throttle position
sensor is a resistor laid in a circular track, and a centrally mounted
brush contacts the track at a position that you can set, in this case by
moving the throttle. on my 89 civic, 5V is applied across the resistor
and the contact can therefore tap in at any point in between - half way
being 2.500V, 1/3 being 1.667V, etc. if you measure the voltage on the
contact on the old tps, then replicate it with the new tps, without
adjusting anything else on the throttle body, it should be calibrated as
before.
i suggest using a low voltage power source doing this with the throttle
body off the car because higher voltage than factory might burn the
resistor. and you're after the differential, not an absolute value.
> This is potentially a real money saver for people
> with this problem on an out of warranty repair.
or it's fun to do if you're a geek with the tools and inclination.
> I understood the rest of it.
> I have used reverse bits to remove studs and shear bolts before and it
works
> pretty well if you drill a small diameter pilot hole in the exact center
of
> the broken stud or bolt. Have even done very small bolts like the ones
that
> hold on the distributor cap. It was a lot cheaper than buying a new
> distributor but it requires a steady hand and the patience of Job.
>
> Where did you learn how to do this? I can't believe Honda put it in a
> service manual.
well, i got the idea from the service manual. the tps fault finding
page has a graph of voltages and throttle position, and it shows idle as
"0.5V", and 5V is the system voltage, so 10% is the place to start
looking, with actual number being the result of calibration. everything
else in the replacement process just depends on how many toys you have!
you can fudge a repair on the tps itself as well, but my advice is
replace it if you can find a suitable donor since actual repair is a pita.
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