pettybird

A couple weeks back, the car started going into limp mode.

The first thought was bad gas, but I just filled it up with Sunoco 94 and there's no change.

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.)

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

I replaced the charge pipe couplers and replaced the hose going to the cycling valve--it was cracked.

Replaced TPS with a known good piece

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.



Why I think it's the KLR:

Even with the WG line pinched, the boost gauge is really sluggish and only reads to 1.5bar 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 fast that way, though not as it should be--I'm thinking the reduced timing is still killing it.

pressure tested the KLR signal line with vacuum from a mightyvac pump--it held pretty well, though it would bleed down. I could not find an issue with the hose itself.

It's definitely going into limp mode--I can activate it on the freeway, cycle the key, and power returns.



Anything else I should check? I need to get an LED so I can check the codes, but it seems like I've covered everything else...


Thanks

Doug

pettybird

OK, not the KLR...what's next?

User 52121

If the WG line is pinched and you're still not getting boost - then I'd look closely at the WG.

It's just a simple mechanical valve - it's sole purpose is to route air away from the turbo when it opens. Pinching the line doesn't let any pressure get to the valve and SHOULD hold it closed (thus giving you more boost.)

If the line is pinched and you're still not getting boost - sounds like your WG is likely toast. That or you have a BIG boost leak somewhere (highly doubtful as it would be pretty obvious IMO.)

pettybird

OK definitely something to look at. if the WG was bad, though, would the KLR still limit my boost? Like I said it takes a definite step down in power I can restore by cycling the key. Also, I have an aftermarket boost gauge coming my way--I'll get true readings in the next couple days.

I have a nice pretty Synapse WG to install with my 3" exhaust...I have a ton of parts for the car but I wanted to do it all at once, and I don't want to do anything until I figure out what's wrong...it's frustrating.


Thanks

Doug

User 52121

Ok I missed the part about cycling the key restores power. That's odd. Almost sounds like you have 2 issues going on here.

By pinching the line going to the WG, you should render the CV ineffective. It shouldn't matter WHAT the KLR is telling the CV to do - with the line pinched, you should get lots of boost. The fact that you aren't means there's something going on there.

pettybird

it could be that I have two issues...looks like it's time to pull the intake and replace more hoses. It's just kind of odd that I'd have an electrical problem AND a mechanical failure at the same time. It's not unheard of, but it's a bit "House MD"ish!

User 52121

I'd start with the WG first. Does the WG hold vac on the Mityvac? (and PS the vac line to the KLR should hold vac too)

pettybird

I couldn't get a good seal on the KLR line banjo fitting. It held PRETTY well but not perfectly. i have a new KLR hose on order from the dealer.

vacuuming the WG is a good idea...I'll have to hope for a dry spot this weekend and try that. It was suggested on Pelican to check the knock sensor, too.

User 52121

Just use regular vac hose. So long as it's small enough to fit snug on the KLR end, you don't need to use the official Porsche hose. It's nothing special.