Fw: tricky URQ questions long

["Scott Bristol" <sbristol@vbe.com>]

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Question for the list.

My '83 TQC has been giving me some problems latley (big surprise!).
First some background. The car has an Intended Acceleration computer with WG
spring. Previously, I had a boost problem that was corrected with special
thanks to Ned Ritchie and Ivor Wigham.

The car has a problem under heavy boost and acceleration. At approximately
4600 RPM, the boost pressure drops completely and reverts to a normally
aspirated condition with very little additional pull. The fuel pump is not
cutting out nor does it appear the computer is alternating ignition spark.
Also, the boost pressure only reaches 11 psi and maintains that pressure
until it cuts out. O.K. I know what you are all thinking--Check for air
leaks stupid. I HAVE! I think I have spent an entire day looking. I have
tried pressurizing the system and spraying soapy water everywhere, using
propane around all hose and manifold gasketts... All the hoses to and from
the intercooler are new. The intercooler itself has been tested as well.

My question is this. I am going to a friends shop this weekend to double
check timing curves, frequency valve operations, and recheck CIS system.
Does anyone have any suggestions that I should check while or before I do
this.

Things I have already checked:
1. replaced wastegate
2. CIS pressure (90psi)
3. Warm-up regulator (fuel)
4. Temperature sensor
5. Air temp sensor
6. CIS fuel screen removed
7. Correct spark plugs
8. replaced virtually all hoses
9. EGR check valve
10. wire continuity for temp, air temp, WOT, and closed throttle switches.
11. computer power and grounds
12. Engine grounds
13. The turbo appears to work fine. (K26)
14. The Air Bypass valves leaks slightly. However, when bypassed problem is
still apparent.
15. fuel volume delivery O.K.

If anyone has ANY SUGGESTIONS before I set fire to it...please let me know.
My last check will be to send the computer to someone to see if the same
problems exist in their car. Any volunteers?

Thanks for the help,
Scott