Prev: '97 Camry timing belt
Next: 1993 Camry Doesn't Shift Until It is Warm
From: mrdarrett on 23 Apr 2007 16:15
On Apr 21, 5:03 am, videokid...(a)hotmail.com wrote:
> On Apr 19, 1:24 pm, videokid...(a)hotmail.com wrote:
>
>
>
>
>
> > On Apr 17, 3:53 am, mrdarr...(a)gmail.com wrote:
>
> > > On Apr 15, 8:09 pm, videokid...(a)hotmail.com wrote:
>
> > > > On Mar 28, 5:38 am, mrdarr...(a)gmail.com wrote:
>
> > > > > On Mar 22, 4:50 pm, johngd...(a)hotmail.com wrote:
>
> > > > > > The ECT you mentioned is a variable resistor, not the ECT switch
> > > > > > (Toyota could better differentiate them like the latter a "fan switch"
> > > > > > everybody else calls.)
>
> > > > > > The variable resistor (near 0 hot, near infinity when cold). But it's
> > > > > > on the water outlet like you described. It doesn't need voltage to
> > > > > > operate.
>
> > > > > > 100ohms is about the low end of the permitted range at around 210deg.
> > > > > > Why do you think it's low or bad?
>
> > > > > > rockauto.com has one for as low as $23.99 (verify your application).
> > > > > > The "fan switch" 36549 is about $50.
>
> > > > > > STANDARD MOTOR PRODUCTS Part # TX40T {TRU-TECH}
> > > > > > $23.99 $0.00 $23.99
>
> > > > > > STANDARD MOTOR PRODUCTS Part # TX40 More Info
> > > > > > $27.79 $0.00 $27.79
>
> > > > > > AIRTEX Part # 5S1517 More Info
> > > > > > $28.79 $0.00 $28.79
>
> > > > > > BECK/ARNLEY Part # 1580421 More Info
> > > > > > $31.79 $0.00 $31.79
>
> > > > > > ACDELCO Part # D583 More Info {#19022018} SENSOR,ENG COOL T/GA
> > > > > > $37.79 $0.00 $37.79
>
> > > > > > FOUR SEASONS Part # 36424 More Info For AC
> > > > > > $54.79 $0.00 $54.79
>
> > > > > This is one of those situations where walking into a store is helpful.
>
> > > > > With shipping, Part # TX40T costs $30+. AutoZone had it for $29.
>
> > > > > I got the ECT sensor from AutoZone, then it turned out it's the wrong
> > > > > part. (It had two prongs for electrical connection. I need a single
> > > > > prong.)
>
> > > > > I really needed the "ECT Switch" (that's what AutoZone calls it).
> > > > > $11.99. Will pick it up today (has to be transferred from another
> > > > > store).
>
> > > > > Michael- Hide quoted text -
>
> > > > > - Show quoted text -
>
> > > > HOW is an ECT going to cause a stall when warm?????
> > > > Just DOESNOT make sense.
> > > > dave- Hide quoted text -
>
> > > > - Show quoted text -
>
> > > I got the idea from this site, when I was researching my stalling
> > > problem:
>
> > >http://toyotaownersclub.com/forums/index.php?s=2fc32630ecb777e2fca911...
>
> > > First post.
>
> > > Pasted here, for your convenience:
>
> > > -=-=-=-=-=-=-=-=-=-=-
>
> > > Problem found and resolved on my fiancés 92 Camry: coolant temp
> > > sensor.
>
> > > After exhibiting all the same symptoms as you all, I went down to the
> > > Toyota dealer who misdiagnosed the distributor and igniter as being at
> > > fault. After they charged and arm and a leg, it stalled at the next
> > > stop light on the way home. Furious at Toyota, but tired and wanting
> > > to get home, I waited for the car to cool enough for it to start again
> > > and carefully drove home, doing the gas/brake deely with both feet.
>
> > > I then took the car to a friend of a friend, a trusted non-Toyota
> > > mechanic that came highly recommended. He had the problem figured out
> > > and solved in 2 days. As I came to pick up the car, he explained to me
> > > what he did and how he figured it out. He had a snap-on computer, just
> > > smaller than the size of a laptop hooked up to several sensors in the
> > > engine compartment; he actually drove the car with wires hanging out
> > > of the hood going through the window to his computer, which acted like
> > > a real-time analyzer and data logger. As soon as the symptom arose, it
> > > was the temperature sensor that caused the fault.
>
> > > As most of you may know, temperature sensors are just over-sized
> > > thermistors, which are devices that output a change in resistance in
> > > proportion to the heat that is detected. The ECU measures this
> > > resistance to determine the temperature of the engine, and based on
> > > such, gives the appropriate amount of fuel to cylinders to combust.
> > > The problem is that over time (at least so I've been told with Toyota
> > > temp sensors), they can fail after getting to a certain temperature.
> > > They would function cold and as they get hotter and hotter, they short/
> > > open and produce a false reading to the ECU. The ECU then sees this as
> > > a malfunction, and thinking that the motor is cold in an effort to
> > > avoid detonation, dumps WAY more fuel than needed and basically floods
> > > the engine. This is why after the car stalls and you try and start the
> > > car unsuccessfully, you can smell a heavy gas odor in/near the engine
> > > compartment. It's putting too much fuel for the temperature of the
> > > motor/air and stalling the motor. This is also why it stalls only when
> > > coming to a stop: because you don't have your foot on the gas to let
> > > more air in to balance out the extra fuel that is being sent into the
> > > engine.
>
> > > Apparently, this is something of an issue with Toyota coolant temp
> > > sensors after a long period of time (at least told to me). I'm so
> > > ****** off with the Toyota dealer you cannot imagine. They cringe
> > > whenever I go down there because they couldn't fix my problem and
> > > charged me for something that wasn't even causing the issue. As far as
> > > I'm concerned, dealers can only fix problems to which they know the
> > > cause of, and do not know for the life of them how to troubleshoot
> > > issues! For this they can all go ........- Hide quoted text -
>
> > > - Show quoted text -
>
> > mmm ok I spose,cant say ive herd of this as being a common problem in
> > fact its a new one on me ,ill replicate it and see what results i
> > get.never stop learning do we?as far as the Ecu reading this as the
> > sole signal to provide mixture adjustment,........I dont think so it
> > is in fact a second tear signal according to my wiring diagram and ecu
> > scematic.possibly was a fault, but im wondering if it was the only
> > fault.
> > dave- Hide quoted text -
>
> > - Show quoted text -
>
> Replicated this fault on the dyno today.In open and closed circuit
> conditions and for approx 45 mins .NO WARM STALL.,Slight hc elevation
> and increase in nox.
> dave- Hide quoted text -
>
> - Show quoted text -


How did you run the experiment? After the car entered closed loop
mode (after running warm for awhile), did you pull off the plug to
simulate a failure? How about pull off the plug and then short, to
simulate a failure by short?

If only running without the ECT sensor plugged in, from the time it
was cold, the computer might never enter closed loop mode, right?

Inquiring minds want to know

Michael

From: videokid400 on 23 Apr 2007 18:17
On Apr 24, 6:15 am, mrdarr...(a)gmail.com wrote:
> On Apr 21, 5:03 am, videokid...(a)hotmail.com wrote:
>
>
>
>
>
> > On Apr 19, 1:24 pm, videokid...(a)hotmail.com wrote:
>
> > > On Apr 17, 3:53 am, mrdarr...(a)gmail.com wrote:
>
> > > > On Apr 15, 8:09 pm, videokid...(a)hotmail.com wrote:
>
> > > > > On Mar 28, 5:38 am, mrdarr...(a)gmail.com wrote:
>
> > > > > > On Mar 22, 4:50 pm, johngd...(a)hotmail.com wrote:
>
> > > > > > > The ECT you mentioned is a variable resistor, not the ECT switch
> > > > > > > (Toyota could better differentiate them like the latter a "fan switch"
> > > > > > > everybody else calls.)
>
> > > > > > > The variable resistor (near 0 hot, near infinity when cold). But it's
> > > > > > > on the water outlet like you described. It doesn't need voltage to
> > > > > > > operate.
>
> > > > > > > 100ohms is about the low end of the permitted range at around 210deg.
> > > > > > > Why do you think it's low or bad?
>
> > > > > > > rockauto.com has one for as low as $23.99 (verify your application).
> > > > > > > The "fan switch" 36549 is about $50.
>
> > > > > > > STANDARD MOTOR PRODUCTS Part # TX40T {TRU-TECH}
> > > > > > > $23.99 $0.00 $23.99
>
> > > > > > > STANDARD MOTOR PRODUCTS Part # TX40 More Info
> > > > > > > $27.79 $0.00 $27.79
>
> > > > > > > AIRTEX Part # 5S1517 More Info
> > > > > > > $28.79 $0.00 $28.79
>
> > > > > > > BECK/ARNLEY Part # 1580421 More Info
> > > > > > > $31.79 $0.00 $31.79
>
> > > > > > > ACDELCO Part # D583 More Info {#19022018} SENSOR,ENG COOL T/GA
> > > > > > > $37.79 $0.00 $37.79
>
> > > > > > > FOUR SEASONS Part # 36424 More Info For AC
> > > > > > > $54.79 $0.00 $54.79
>
> > > > > > This is one of those situations where walking into a store is helpful.
>
> > > > > > With shipping, Part # TX40T costs $30+. AutoZone had it for $29.
>
> > > > > > I got the ECT sensor from AutoZone, then it turned out it's the wrong
> > > > > > part. (It had two prongs for electrical connection. I need a single
> > > > > > prong.)
>
> > > > > > I really needed the "ECT Switch" (that's what AutoZone calls it).
> > > > > > $11.99. Will pick it up today (has to be transferred from another
> > > > > > store).
>
> > > > > > Michael- Hide quoted text -
>
> > > > > > - Show quoted text -
>
> > > > > HOW is an ECT going to cause a stall when warm?????
> > > > > Just DOESNOT make sense.
> > > > > dave- Hide quoted text -
>
> > > > > - Show quoted text -
>
> > > > I got the idea from this site, when I was researching my stalling
> > > > problem:
>
> > > >http://toyotaownersclub.com/forums/index.php?s=2fc32630ecb777e2fca911...
>
> > > > First post.
>
> > > > Pasted here, for your convenience:
>
> > > > -=-=-=-=-=-=-=-=-=-=-
>
> > > > Problem found and resolved on my fiancés 92 Camry: coolant temp
> > > > sensor.
>
> > > > After exhibiting all the same symptoms as you all, I went down to the
> > > > Toyota dealer who misdiagnosed the distributor and igniter as being at
> > > > fault. After they charged and arm and a leg, it stalled at the next
> > > > stop light on the way home. Furious at Toyota, but tired and wanting
> > > > to get home, I waited for the car to cool enough for it to start again
> > > > and carefully drove home, doing the gas/brake deely with both feet.
>
> > > > I then took the car to a friend of a friend, a trusted non-Toyota
> > > > mechanic that came highly recommended. He had the problem figured out
> > > > and solved in 2 days. As I came to pick up the car, he explained to me
> > > > what he did and how he figured it out. He had a snap-on computer, just
> > > > smaller than the size of a laptop hooked up to several sensors in the
> > > > engine compartment; he actually drove the car with wires hanging out
> > > > of the hood going through the window to his computer, which acted like
> > > > a real-time analyzer and data logger. As soon as the symptom arose, it
> > > > was the temperature sensor that caused the fault.
>
> > > > As most of you may know, temperature sensors are just over-sized
> > > > thermistors, which are devices that output a change in resistance in
> > > > proportion to the heat that is detected. The ECU measures this
> > > > resistance to determine the temperature of the engine, and based on
> > > > such, gives the appropriate amount of fuel to cylinders to combust.
> > > > The problem is that over time (at least so I've been told with Toyota
> > > > temp sensors), they can fail after getting to a certain temperature.
> > > > They would function cold and as they get hotter and hotter, they short/
> > > > open and produce a false reading to the ECU. The ECU then sees this as
> > > > a malfunction, and thinking that the motor is cold in an effort to
> > > > avoid detonation, dumps WAY more fuel than needed and basically floods
> > > > the engine. This is why after the car stalls and you try and start the
> > > > car unsuccessfully, you can smell a heavy gas odor in/near the engine
> > > > compartment. It's putting too much fuel for the temperature of the
> > > > motor/air and stalling the motor. This is also why it stalls only when
> > > > coming to a stop: because you don't have your foot on the gas to let
> > > > more air in to balance out the extra fuel that is being sent into the
> > > > engine.
>
> > > > Apparently, this is something of an issue with Toyota coolant temp
> > > > sensors after a long period of time (at least told to me). I'm so
> > > > ****** off with the Toyota dealer you cannot imagine. They cringe
> > > > whenever I go down there because they couldn't fix my problem and
> > > > charged me for something that wasn't even causing the issue. As far as
> > > > I'm concerned, dealers can only fix problems to which they know the
> > > > cause of, and do not know for the life of them how to troubleshoot
> > > > issues! For this they can all go ........- Hide quoted text -
>
> > > > - Show quoted text -
>
> > > mmm ok I spose,cant say ive herd of this as being a common problem in
> > > fact its a new one on me ,ill replicate it and see what results i
> > > get.never stop learning do we?as far as the Ecu reading this as the
> > > sole signal to provide mixture adjustment,........I dont think so it
> > > is in fact a second tear signal according to my wiring diagram and ecu
> > > scematic.possibly was a fault, but im wondering if it was the only
> > > fault.
> > > dave- Hide quoted text -
>
> > > - Show quoted text -
>
> > Replicated this fault on the dyno today.In open and closed circuit
> > conditions and for approx 45 mins .NO WARM STALL.,Slight hc elevation
> > and increase in nox.
> > dave- Hide quoted text -
>
> > - Show quoted text -
>
> How did you run the experiment? After the car entered closed loop
> mode (after running warm for awhile), did you pull off the plug to
> simulate a failure? How about pull off the plug and then short, to
> simulate a failure by short?
>
> If only running without the ECT sensor plugged in, from the time it
> was cold, the computer might never enter closed loop mode, right?
>
> Inquiring minds want to know
>
> Michael- Hide quoted text -
>
> - Show quoted text -

replicated using scan tool.
dave

First  |  Prev  | 
Pages: 1 2 3
Prev: '97 Camry timing belt
Next: 1993 Camry Doesn't Shift Until It is Warm