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Bypass CTS


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Can I bypass the CTS for diagnostic purposes?  Mine doesnt have a plug.  I can switch wires to either side.  Is there a right/wrong way to have the wires?

 

Not sure if its the culprit or not.  86 Turbo GL10.

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yes ! but, tell us what it is doing you are chasing, and tell what it does when you bypass it.

 

I think some sort of potentiometer device would be handy for this sort of diagnosis. Find out range of CTS, get a few, dunno say 10 different resistors of the range values and switch between them in order to see if baby runs better at any particular value - like you tell the ECU a known resistance and see what it does to the running.

 

Maybe an old fuel gauge sender unit could be similar range needed to be read from ECU, connect up and run with a diagnostic person operating it - or a slot car trigger to provide the variable ??

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"Potentiometer" huh?  You highly overestimate me.  LOL!

 

I replaced the CTS.  The plug was broke so I afixed a couple connections and stuck them on.  Not sure if there was a right or wrong way.  I wouldnt think so but who knows.

 

It starts hard.  More hard when its warm.  Sometimes it idles fine [warm] and sometimes it will drop to 450-500 and try to idle.  Almost like its missing.  Check compression and checked to see if its missing, and its not.  Its not flooding, it seems to be leaning out if anything.  I'll hold the pedal down to 1700rpm.  After about 30 secs it will start to run right again.  No smoke.

 

Maybe a weak fuel pump?  Just not sure.

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I checked one in a manifold I have loose here.  It seems that the sensor is isolated from the housing, so the wires should not matter.  You can double check with an ohm  meter.  If the meter shows open circuit to ground from both wires, it won't matter.  The FSM has ohm readings for a few temperatures, so you could try connecting a fixed resistor for the current temp of the engine, but it will be wrong when the temp changes, obviously. 

 

It might be worth checking the resistance at the ECU connector pins also.  a bad connection in the harness could cause bad readings also.

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