When I bought the car, no issues with it. Suspension is a little clunky, as it should be for 150,XXX miles. I parked with my wife to have lunch shortly after getting the car. While idling there (enjoying the heated seats) I wanted to hear the motor a bit. I very VERY gently tapped the throttle, maybe a bump of 200RPM, if that and I got a Check Engine Light. Well crap...that didn't take long. I put 10 miles on it? If that. Anywho, made the 3 hour drive back up north of Seattle where I live with no issues. Noting that the CEL had a slight flicker every now and then. I checked online for a non-symptomatic CEL and found it's not too uncommon. Next day I went to my local O'Reilly's to use their OBDII sensor and find out what's going on.
What I found was this:
P0033: "Turbo Charger Bypass Valve Control Circuit Open
P0411: "Secondary Air Injector, Incorrect Flow"
P3144: "Misfire Detected, Cyl #4"
Okay, so I have a start. I went ahead and bought new oil (Mobile 1 because they didn't have AmsOil and a premium Wix filter), a set of Double Platinum Spark Plugs, headlight restore kit, and other minor things. They didn't have the spark plugs in stock, so I had to wait a day. Not terrible.
First thing first, the Turbo. I decided to pay attention to that the most because even though a "misfire" was detected, the car idles fine, drives fine, no issues. I did some research to this P0033 code and the P0411 code (thinking they were within the same system, I was wrong) and found that commonly the vacuum lines to the bypass valve on the turbo can have holes, or cracks causing this code. Also mind that this is the first turbo I've touched besides aircraft turbos.
I checked out a few parts catalogs and found a nice website with microfiche break downs of every component. Ordered OEM vacuum hoses and the Charge air Bypass Valve solenoid. That would be taking a few days to get here so I decided to go into the bypass valve itself located just under the intake side of the compressor.
Not the most convenient location, but I got it off. It was spring loaded with a plastic puck inside, so removal was careful. Looked around and BAM! There's a small hole in the diaphragm!
So there's the cause of that problem. and I was driving around thinking that "turbo flutter" was normal! So I made a few calls, did some looking. $250 for a replacement kit...NO. I RTV'd it, that's right. Liquid gasket. I bought the highest temp and pressure rating, put a small dot on both sides and let it cure. I didn't do the full 24 hours as it recommended, but I did let it set for roughly 4 hours while I worked on an annoying project.
That annoying project was my cabin air fan. Made this AWFUL clicking sound, I knew it had to do with either a broken fan blade hitting something, or it was the brushes contacting the motor. So I took off the paneling and most everything of the passenger side.
It was in fact the brushes contacting the motor. I wish I took a picture of it. The brushes are...well...150k old, to the point where it was wearing the copper contacts on the motor itself. I have to say, I don't think I've seen that for the years I've been a mechanic. So, cleaned everything up, sanded the brushes and contacts and reassembled. Mostly gone, it actually got worse for 2 days and now the noise is almost not even present at low speeds. Can't hear at high because there's too much air flowing. It's quite a fan, pushes a LOT of air through many vents.
Back to the bypass valve. After messing with that cabin fan, I reinstalled the bypass valve. I should have made an index mark on it when I removed the cover. It's circular in shape with 3 bolts triangulated on the cover with maybe 2MM difference between 2 of the 3 bolts, leaving little room for error whilst fighting the spring tension and trying to get the gasket matched. Took longer than I want to admit.
Reinstalled and went for a drive. Started the car and noticed a ticking sound on the intake side of the motor. But it went away after about 2 minutes of warming up (I didn't think much of it at the time). Took it out and I had that perfect dispersal of pressurized air being decompressed rather than fluttered back into the turbo. Perfect, now to find a permanent fix. I stumbled into the Forge Turbo Air Bypass Valve for $140. It's a "performance" part, as much "performance" as you can get from a bypass rather than a blow-off valve. Uses a metal piston and o-ring assembly rather than a rubber diaphragm. That's ordered and will be here December 21st!