![]() |
|
|
|
Registered
Join Date: Jun 2009
Posts: 1,241
|
3.2 head temp sensor.
Wonder if I have this understood correctly. A 3.2 head temp sensor is a variable resister that filters a low voltage signal to the DME changing the fuel mixture as the engine warms up. My understanding of one other component of that system is, once warmed up, the DME has a default chip or driver that will deliver the correct fuel mixture regardless of the what the head temp sensor is doing and as long as the engine is at operating temp. I suppose I could warm up a 3.2 and unplug the sensor to find out, but it may be a bit more involved than that, so thought I would ask. Thanks for any illumination offered. Bob
|
||
![]() |
|
Registered
|
Yes it is more involved, I know an open head temp sender will cause a no start! DME uses the variable output as one perameter for the mixture and timing.
|
||
![]() |
|
Registered
Join Date: Dec 1999
Location: Novato, CA
Posts: 4,740
|
From my experience, disconnecting the cht sends the DME into full rich and may or may not start.
|
||
![]() |
|
Registered User
Join Date: Sep 2019
Posts: 12
|
Am I correct in assuming that:
Higher resistance (cold) produces a richer mixture Lower Resistance (hot) produces a leaner mixture |
||
![]() |
|
Registered
Join Date: Jan 2009
Location: Marietta, Ga (Atlanta)
Posts: 2,970
|
You are correct Sir!
__________________
'80SC Widebody 3.6 transplant Anthracite "The Rocket" Long gone but still miss them all: '77 911 Targa, '72 BMW 3.0CS Coupe(finest car I ever had!) '71 911T Coupe White, '70 911T Coupe Blue '68 911 Coupe Orange, '68 911L Soft Window Targa |
||
![]() |
|
Registered
Join Date: Dec 1999
Location: Novato, CA
Posts: 4,740
|
Perfect definition of a NTC (negative temperature coefficient) resistor.
|
||
![]() |
|
![]() |