What happens to driveability when...

[S10xGN]

... you have the boost sensing cable in place of the MAT sensor? My truck stumbles bad and idles like cr@p when it goes closed loop. After it's hot, if you shut it off, then restart after > 10 minutes, you have to sit and feather the throttle until it goes into clsoed loop for it to stay running (stalls).

 

[JDEstill]

An experiment: does it run any better when you take the boost sensing cable off and put everything back to normal? Not to be a smart ass or anything

I never noticed my GN running any different when I had the boost sensing cable on it. As far as what happens, your ecm will be seeing the MAT jumping around as manifold pressure changes. Depends on your chip I think whether or not the ecm makes any adjustment based on that.

John

 

[JayC]

It shouldnt make any difference.

 

[bruce]

Originally posted by S10xGN
... you have the boost sensing cable in place of the MAT sensor? My truck stumbles bad and idles like cr@p when it goes closed loop. After it's hot, if you shut it off, then restart after > 10 minutes, you have to sit and feather the throttle until it goes into clsoed loop for it to stay running (stalls).

Are you sure you have a 3 bar sensor?.

 

[S10xGN]

John: it seems like I've tried that, but my memory is unclear, so maybe I'll do it again to be sure (getting old sucks!).

Bruce: I'm pretty sure I've got a 3 bar, but what difference would it make to the idle quality? And how could I tell for sure that it is a 3 bar sensor?