ST185 Check Engine Light: Code 52

Soooooooooo, it seems I was enjoying my new All-trac just a little too much, and because fate loves to deal me out fat FUCK YOU's now and then, the Celica seems to have developed a not inconsequential problem.

Story time.

I'm driving home from work, car ahead of me is going REALLY slow, so I go to 4th gear and floor it to pass, car spins up just fine, then as boost crests the end of the in dash gauge, the check engine light comes on. Basically full throttle pull, hit high boost (which the ECU already doesn't like because I have a CT27 turbo with no fuel cut defender) engine goes into limp mode. I pull off the highway, get it too a parking lot, jerry up a nice little diagnostic paperclip, and get the code. Comes back 52. Knock Sensor, code. Well shit.

Cars sits and idles fine, no smoke out the rear, temperature is good, no funny smells or sounds.

Unplugged battery to clear codes, idled fine without issues (when warm, when cold there's a surging issue, but more on that later), but as soon as I load the engine, bam, code 52 and limp mode for me.

Considering I just spent 5k on the car, I'm eh, not happy. Anyway, thoughts on causes? Solutions? Dark Gods I can petition to cure my engine ills?

Also, the surging. Every since I got the car I've noticed that as it starts to warm up, it stumbles and surges occasionally at idle, but only at idle, and the issue goes away completely when the car is warmed up. Doing some visual inspections, I cam across this little bastard.

http://i.imgur.com/sQ2Hz0s.jpg

A big fat crack in the intake boot, just PAST the MAF. Or at least what I assume is the MAF, and before the turbo. Prodding at it while the car is running results in it stumbling, then dying, so I'm pretty sure it's sucking in air there, after the MAF, and causing a lean run condition. Could this also somehow piss off the knock sensor? If so, why does it now enter limp mode immediately upon giving any kind of throttle? Or has the knock sensor perhaps been damaged by overboost and heat? I don't think the car has had an actually knock issue, as I've never heard any irregularities or anything that sounds like knock. Then again, I'm only a shadetree mechanic and far from any kind of expert.

it happened to me in the past and was the knock sensor that was broken.

anyway fix the crack in the hose as soon as possible because as is the engine runs super lean and could overheat (and also knocking), you could use some black silicone for a temporary fix and see if the error goes away

Replace the intake hose and replace the knock sensor.

By the time you can hear knock, you're engine is gonna be FUBAR. As others have said replace that broken coupler, you're gonna run lean with that unmetered air getting in.

Aye, hose fix in happening asap. Got some loctite self fusing silicone tape on the way, which supposedly works well for fixing this sort of thing. Hopefully it'll do until I can figure out a more permanent replacement for that hose.

As for the knock sensor, my mechanic will be fixing it while I'm on vacation. Not stoked about the fact that the only knock sensor he can get is $200 though.....

I read once that you can adapt a GM knock sensor that is super cheap

There is, but it requires an adapter for the block [it doesn't thread into the stock hole] and you have to splice in a new/different connector.
This is/was? an "accepted" fix but I'm not personally comfortable with it because the GM sensor "listens" on a different frequency.

For your intake hose if you're staying with a stock style setup I suggest something smooth like the Samco intake hoses.

Plus if you're going through knock sensors fast enough to justify the adapter and wiring change to convert to the GM one I think you've got bigger problems you should be worrying about.

UPDATE: Alright folks, it took a little while, but my little red animal is fixed. More or less. The crack in the intake hose has been thoroughly wrapped and sealed with that red loctite self fusing silicone wrap. It's neat stuff! Granted it's not a permanent solution, but it'll last until I can order a new pipe on Friday. So with that sealed and the knock sensor replaced, the CEL has been appeased and it's smooth sailing. Whats more, with that pipe sealed it seems the stumbling idle issue I was having has also been fixed, and it's making noticeably more power at lower end of things. All in all, it turned out pretty well.

Now to get the bushings in the rear replaced, the diff plate, and the bushings in the front done. Anybody know what to do about oil and steering pump fluid eating the tie rod bushings?

i'm happy you fixed it, for the steering pump get a repair gasket kit at toyota, it's cheap and the repair is simple.