86 5kTQ breakup - more information

[charlie@elektro.cmhnet.org (Charlie Smith)]

This is a followup to my earlier discussion of misfiring problems 
I'm experiencing with my 86 5kTQ.

When I was getting the check engine light above 3000 rpm, the 
computer stored a code of 2222, which is "Pressure sensor defective".

Installing the second computer, the MAC-11, cured the check engine
light.  The max boost indicated in the dashboard readout is 1.3 to
1.4 bar; which is much lower than the 10 or 11 psi indicated with my 
mechanical guage.  The guage it "T" connected to the pressure line
just before it enters the computer.  This seems to me to indicate
the pressure sensor in the MAC-11 is either mis-calibrated, or the 
MAC-11 isn't compatible with my car which was set up for a MAC-10
computer.  Before any mods, the max boost indicated (with the MAC-10)
was 1.3 bar.  Clearly, the dash readout is incorrect now.

The car has 165,000 miles on it, but is in relatively good condition.
It doesn't use any oil, and has compression of 120, 120, 120, 130, 115
when taken with the engine warm.

When I run the car now, I do not get any check engine light even when
I can hear it breaking up above 4000 rpm.


Charlie Smith   charlie@elektro.cmhnet.org  614-471-1418  

   Fleet:
86 5kTQ      
69 Porsche 911S   3,200cc
92 Ducati 851SP     851cc
95 BMW R100-RT    1,000cc
62 BMW R27          250cc