[Pettybird]

A couple weeks back, the car started going into limp mode. I'm more than a little frustrated after laying out cash and a couple days' worth of work to no avail. I'm ASE certified, have worked as a parts counter guy and a service writer, and I'm still stuck saying "all of a sudden, it just happened." I couldn't find any odd issues with wiring (that I can see on a fully assembled motor) and I didn't do anything to the car to precipitate the change.


Symptoms:

Even with the WG line pinched, the boost gauge is really sluggish and only reads to 1.6bar when, prior to a couple weeks back, it would peg at 2 bar (autothority stg.2 chips.)

I pinched the wastegate feed line from the cycling valve. The car's a little faster that way, though not as it should be--I'm thinking the reduced timing is still killing it, and the boost gauge still doesn't peg.

It's definitely going into limp mode--there's a decrease in power you can feel, then a BIG drop when the boost drops to 1.2 bar. I can activate it on the freeway, cycle the key, and power returns for another 8-10 seconds.



Here's what the problem ISN'T :

The first thought was bad gas, but I ran the tank empty and refilled it with Sunoco 94.

I checked the vacuum lines, and all are connected. I played around with a bunch of them anyway--the connectors are horrible after 23 years, and new ones from the dealer are now at my house. I can't see any that have fallen off or broken at this time.

Replaced the BOV with one of those fancy billet ones--I had it lying around anyway.

Replaced the charge pipe couplers

Replaced the hose going to the cycling valve--it was cracked.

Replaced TPS with a known good piece

Replaced the KLR with a known good piece

Pressure tested the KLR signal line with vacuum from a mightyvac pump--it held. I could not find an issue with the hose itself.

Pressure tested the fuel system--30psi with the vacuum line connected and 34psi disconnected. Pressure holds steady when revving engine. I'm still running the stock FPR, so this seems normal.


Still nothing! Anything else I should check? I need to get an LED so I can check the KLR codes, but it seems like I've covered everything else...


Thanks

Doug