3 temp sensors

[SevenT6Vet]

please confirm this:

side of block coolant sensor does gauge
intake manifold coolant sensor does ecm (not shown in data logger)
MAT sensor in side of plenum does intake air temp to ecm (shown in data logger).

I think my starting problem is linked to that manifold coolant sensor. the gauge one is new (and works). the MAT sensor i've confirmed is OK due to data log.

i'm looking through my GM syty books to see if there is a test for the upper coolant sensor. i may just go buy a new one to be safe.

 

[berzerker]

Re: 3 temp sensors

to test your cts in the lower intake . connect datamaster or your availible logger . look at the coolant temp value when engine is cold . should be pretty close to the ambient air temperature . i.e 76 deg. .. if it reads something like - 40 degrees or 260 degrees your cts sensor is junk and needs replaced . make sure the sensor wiring connector and wiring are in good shape before a new sensor purchase . good luck .

 

[SevenT6Vet]

Re: 3 temp sensors

to test your cts in the lower intake . connect datamaster or your availible logger . look at the coolant temp value when engine is cold . should be pretty close to the ambient air temperature . i.e 76 deg. .. if it reads something like - 40 degrees or 260 degrees your cts sensor is junk and needs replaced . make sure the sensor wiring connector and wiring are in good shape before a new sensor purchase . good luck .

crap, just relooked at data logger and found the coolant temp spot (missed it first time)....it's within a few degrees of IAT. ugh, i was really hoping i found my starting issue.