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Temp II Sensor...Resistor? Why..

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Old 09-30-2011, 11:57 PM
  #16  
smiffypr
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There's no way to tell, but it will be a step in the right direction.
The addition of the resistor "suggests" that there is another issue.
The fact that it runs with the temp II sensor disconnected, suggests there is another issue too.
You will have to go through a full diagnosis, i.e. testing each component in the system either by following any tests in the WM (e.g. resistance tests of tempII, measured at the ecu), or by substituting known good components.
Old 10-01-2011, 01:03 AM
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risaac928
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Looks like I will swapping out parts...unitl one hits...This SUCKS...By replacing the Temp II Sensor and its cap does and if that does not work...I dont know what the next step will be. Replacing the resistor?

Question, by putting a meter to the cap of the Temp II resistor, what will that tell me?
Old 10-01-2011, 07:40 PM
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risaac928
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Well I replaced the Temp II Sensor and as suspected, the car will only start with it disconnected. Once I have the car started, I attempt to reconnect the Temp II Sensor only to have the accelerate rapidly then die....Please help...
Old 10-01-2011, 08:13 PM
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Originally Posted by smiffypr
All of this suggests that there is a problem with something else, and the resistor was added to compensate for the other problem. Much better to find the other problem and fix it.

I have no experience of L, just K and LH, and from K I know that the mixture adjustment according to temperature varies in the warm-up range, but once the engine is warm (above 65 C), the mixture is not adjusted any more when it goes from warm to hot. This suggests that mixture adjustment is not desirable at these temperatures, and that to fool the ecu into richening the mixture, we have to fool it that the temperature is down in the warm-up range. What this will mean is that the slight variations in temperature as driving conditions change will be constantly causing mixture changes when it is not desirable.
Do you think the resistor is dead/bad?
Old 10-01-2011, 08:54 PM
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928mac
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You need to understand.

This sensor tells the computer how cold it is outside, or in reality how cold the engine is. That is all it dose.

The computer uses this information to decide how much fuel it needs to run.

Most Temp sensors when unplugged tell the computer that it is 40 below/-40

If you understand that an engine needs way more fuel to start and run when at that temp it should tell you that you are running way lean with it plugged in, less fuel / normal/ unplugged lots of fuel / normal.

You have a vacuum leak or very low fuel delivery.
The same thing you were told in post #2

on my 89 it did a similar thing but once it started it raced at 3000 rpm
a hose popped off under my intake and I had to remove the intake to find it.

I would suggest by removing the intake and checking all hoses for cracks or anywhere air can leak by.
Other then that I have no experience with the fuel system on your car and someone else will have to chime in if you do not find any leaks.

IMHO
Brad
Old 10-01-2011, 09:16 PM
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risaac928
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Originally Posted by bwmac
You need to understand.

This sensor tells the computer how cold it is outside, or in reality how cold the engine is. That is all it dose.

The computer uses this information to decide how much fuel it needs to run.

Most Temp sensors when unplugged tell the computer that it is 40 below/-40

If you understand that an engine needs way more fuel to start and run when at that temp it should tell you that you are running way lean with it plugged in, less fuel / normal/ unplugged lots of fuel / normal.

You have a vacuum leak or very low fuel delivery.
The same thing you were told in post #2

on my 89 it did a similar thing but once it started it raced at 3000 rpm
a hose popped off under my intake and I had to remove the intake to find it.

I would suggest by removing the intake and checking all hoses for cracks or anywhere air can leak by.
Other then that I have no experience with the fuel system on your car and someone else will have to chime in if you do not find any leaks.

IMHO
Brad
I replaced the fuel filter and the strainer in the tank. Now I did have a fuel leak and I used an epoxy filler to seal the tank. It is likely I got some of the epoxy in my fuel system. Once I repaired the tank I drove the car for about a week or two without any issues.

However the car does start and idle with the Temp II Sensor disconnected only.

If it is a fuel system issue then that would mean I would need to replace the injectors or have them cleaned. What other components of the fuel system would need to be replaced.

I will replace all of the vacuum hoses and report back later....thank you for the help and to all who have read and are following this thread...
Old 10-04-2011, 02:45 AM
  #22  
mark kibort
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make sure you have the tempII sensor conected properly, and havent mixed the temp II with the tempurature sensor for the water jacket.

remove the airflow meter and air filter housing and try and start it that way
that way you can see if there is a senor making things fat by having the AFM not connected to the "U", you can tell if somethng else is to blame.

Originally Posted by risaac928
Well I replaced the Temp II Sensor and as suspected, the car will only start with it disconnected. Once I have the car started, I attempt to reconnect the Temp II Sensor only to have the accelerate rapidly then die....Please help...
Old 10-04-2011, 02:36 PM
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Mark .... Thanks...and your right something else was to blame. There was a vacuum leak. A plastic .10 cent cap popped off the throttle body. rerereading the prior post help uncover the issue
Old 10-05-2011, 02:34 AM
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Always nice to see the problem discovered! good job!



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