Temp related low boost

SuffolkD@aol.com SuffolkD at aol.com
Mon Sep 19 22:58:28 EDT 2005

Someone correct me if I'm wrong, but there are two cut offs?

One is what you describe IN REVERSE.............
I get 1.3/4 until the temp gets to halfway on the gauge, then 1.6/7 "chipped" 
2.5 PT.

The other cut off would be temp sensor being too high, most likely the ACF 
cuts out too at that point.

This sound right?

Ya know fuel will lower boost, al these test done on the same drive / tank of 
-SCott by BOSTON

> From: Tom Ellis <>
> Alright folks, here is one that I hope you can help me with.  For the past
> month or so I've noticed that my boost is limited to 1.4 bar once the engine
> temperature (as shown by the coolant temp gauge) gets above a certain point.
> On the temp gauge this seems to be at the thin line halfway to the first
> thick line, where that thick line is normal operating temperature.  At
> coolant temps below the "thin line" I get full boost to 1.8 bar.
> This does not seem to correlate to oil temperature.  Driving on the freeway
> on a cool evening with the coolant gauge showing a temp at or below the
> "thin line" and oil temps somewhere between 60 C and the next mark on the
> oil temp gauge, I get full 1.8 bar no problem.  But once the coolant temp
> rises above that magic line (regardless of oil temp) maximum boost drops off
> immediately to 1.4 bar.
> I've looked in the archives and found a reference to a possible problem with
> the MFTS that might cause these symptoms.  So I disconnected the MTFS and
> drove the car - same results.
> Thanks for any suggestions!

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