Coolant temperature sensor fault causing low boost

Brett Dikeman brett at
Sat Jul 10 22:21:24 EDT 2004

At 10:02 PM -0400 7/10/04, TM wrote:

>Now following the radiator replacement, I've found that I still
>have a low boost problem after the engine is hot- pulled codes
>and found coolant temperature sensor, intermittent fault.
>Doing the Bentley diagnostic, it seems like the multifunction temp
>sensor is fine, this doesn't really make sense.

It's referring to a different sensor- back of the block, towards the 
passenger side, is the ECU's coolant temp sensor.  It's used 
primarily(I think) for timing and initial starting- not sure on 
either of those, SJM's site probably covers exact functionality.  If 
it fails, the ECU assumes worst case scenario- maximum measurable 

On the NA 20v cars, the connector contacts get pulled out, so that 
might be worth a check, as might a spritz of contact cleaner.

Oh, also, occasionally someone finds the plugs mixed up since there 
are multiple 2-pin connectors there.  The intermittent code probably 
means the right plug is in the sensor, but if you're feeling extra 
paranoid, check the wire colors against the diagrams.

"They that give up essential liberty to obtain temporary
safety deserve neither liberty nor safety." - Ben Franklin

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