99 Honda Accord temp gauge question

Tegger wrote:
(snip)

Just for giggles, went into the garage with a flashlight, and popped the
connector off. The stud on the sender seemed shiny, but the connector
came off awfully easy. Perhaps a fine layer of corrosion adding to the
resistance? Next above-freezing day, I'll try cleaning the hole in the
connector, and maybe gently squeezing it a tad to tighten it up.

 

Or, if you don't have a scan tool, or don't trust the sensor, then with
a cold engine take off the radiator cap and stick a meat thermometer in
the water. Run the engine until the temperature stabilizes. If it's
far too low, it's the thermostat. If it's right or nearly so and the
gauge reads low, go after a gauge problem.

My money's still on the 'stat.

 

Oops. I looked at the headers from the wrong post, evidently. The headers I
saw indicated a poster from Santa Clara.

I guess you'd say I'm in Alta Ontario. Not many Honda mechanics up here
either. The ones we do have tend not to be very good.

 

I'm...I'm...crushed! So I've been believing a lie all my life!

This past summer we went all the way into Toronto to see the Jays play
the I-Forget-Who's (Jays won). The seats came free via my daughter's ball
club and BOY were they cheap seats. We were about four rows from the very
top.
It was still lots of fun, even though the beer was about $100 a cup so I
didn't buy any, and they ran out of Slush Puppie mix.

 

That's OK I've lived less than an hour from the HOF in Cooperstown most
of my life, and I've NEVER been there?

 

How do you find the accuracy of that IR thermometer? Did info
come with it stating a plus and minus tolerance? Have you tried
to determine its accuracy? What's its minimum/maximum range?

I have a Radio Shack (SMART2 model 22-17A) cheap (not to buy)
Fluke-knock-off VOM digital meter, which has a temperature probe
(and capacitor checker and frequency checker MHz/kHz/Hz).

Temps over 300F/150C will blow the stupid oddball (weird amp ratings,
63 mA) internal fuses on it, but I checked its accuracy and it is almost
dead on at the freezing (32F/0C) and the boiling point temp (which at
295ft altitude is slightly less than 212F/100C by I forget how many degrees,
there is a calculator on the internet to find the boiling point temp for
different altitudes).

The manual states +/- 3.6F/2C tolerance, but it tests much better than that.

To test for 32F/0C is easy for any thermometer, use a well stirred
container with crushed ice (heavy on the ice, almost all ice) and water.
The water will get to 32F/0C.

Boiling temp is a little more fussy, steam obscuring view etc., trying to
maintain an even boil etc., finding the altitude and calculating the
boiling point etc..

Are you confidant with the readings your IR produces? I only ask because I
have a zillion thermometers, and none of them read the same when I put
them together in one place! The RS probe is good because I know its
accuracy, but its a pita to drag out, and install all the batteries etc..

Sadly just about all the damned old condensers (Hitachi, Nippon Denso,
AC Delco, Briggs & Stratton etc.) in my junk pile, that I replaced decades
ago as a matter of course, tested the correct microfarads with the condenser
tester. Well at least those little cans were cheap.

 

(M.A. Stewart) wrote in

My IR thermometer is an "UltraPro 95152" that carries the NAPA logo. It
cost about $74/$80 at NAPA. It did come with documentation, but I can't
find it just now.

Its sensing cone width is the distance from the object divided by eight.
That's printed directly on the thermometer's body.

Its maximum range appears to be determined by the size of the thing
being measured. On a car, I'm never more than a foot or 18" away from
whatever I'm measuring, which appears to be sufficient. Minimum is as
close as I can get without radiant heat being sensed by the thermometer.
I pointed it up at the clear blue sky in the middle of summer and got
zero F, for whatever that's worth.

I checked its accuracy against the hot water out of a tap at home, which
I know is regulated to 140F. That was further checked with a candy
thermometer. The IR was dead-on with the candy thermometer, or about as
dead-on as I could determine, since the candy thermometer moved very
slowly and was never quite still.

The thermometer is probably not spot-on to the very last degree, but I'm
not using it for that purpose.

Both our cars have 78C thermostats. I get 205F at the upper rad hose
inlet of both vehicles when their cooling systems are working properly.

When my car began to suffer overheating problems two summers ago, I
successfully determined that the overheating DID indeed exist because as
the temp gauge began to climb, the temperature at the upper rad hose
inlet began to climb to well above 205. (It turned out the rad face was
clogged with oily rustproofing gunk; a garden hose blast fixed it).

I know what a cooling system should read in various places. I know what
a cat should read at inlet and outlet. I know that the brakes should be
pretty much the same temperature across the axle, and that front brakes
ought to be significantly hotter than the rear ones. I can reliably use
it to determine how effectivly the air-conditioning system is working.

If the IR thermometer was off by two or three degrees, that would not
impair my ability to use it for automotive troubleshooting, but I
suppose I wouldn't be able to trust it for lab use.