Turbo trouble, Help!

[celica83_gts]

OK, I'm at my wits end. I thought I had this fixed, but NO! My car runs great under vacuum, all the way to atmospheric pressure. Under boost pressure though, it's a different story.

The engine sputters like a misfire under boost. There seems to be no pattern, just random stumbles. Sometimes it'll pull steady, other times it fumbles a lot, and then others it'll just miss a beat or two. I THINK I hear air escaping when it happens, not too sure because there's a lot going on under boost conditions, like high speeds!

I am pretty sure the ignition and fuel delivery are good, most parts are new and fuel pressure is steady. My guess is boost is escaping somewhere, like the wastegate actuator or maybe the fast idle valve.

I plan to eliminate and cap off as many lines as possible, like cruise, fast idle etc. as well as removing the manual boost controller to see if any of these are the culprit.

Do these symptoms sound familiar to anyone? This is my first turbo car, I'm wondering if others may have experienced anything similar.

I will still show at the track Friday evening, hopefully running better!

Thanks, Bob

[GOT_BOOST]

Hi Bob,

First off I would like to welcome you to the world of turbo troubbles. LOL

It sounds like it could be a number of potential things. It sounds to me like you could be detonating. Have you changed the octane of fuel you use, or what about your ignition timing? Is everything still tight and secure that controlls the timing?

I would also check your ignition wires. It may be that they have become dis connected somewhere along the line, or maybe they are toast and there is a break in the wire where you can not see it. This happened to my Sentra.

Hope this helps.

Mike Nikolai

[Supra_devil]

i would check ignition and timing as well, after the car has worked up and/or maybe heatsoaked a little bit in traffic then bad wires and timing could be causing problems.
Fuel could be it but i assume you use high octance from a decent place.
i would check for vaccum leaks and/or loose clamps. maybe there is a crabked hose somewhere that only leaks after getting shaken the right way or something.
i offer my help as ussual to help a brother in need, if you need tools, an opion or just a helping hand, well you got my number on the list.

[celica83_gts]

Troubles continue. I thought I had it licked when I disconnected the PCV system and the engine ran good again. I think now that the PCV was more of a symptom than the actual problem.

Here's a rundown of what I have now.
1: Oil in the intake from the crankcase breather on.
2: Erratic idle.
3: Trailerhitching at cruise.

I'm thinking now that I'm getting false air somewhere after the AFM. I've eliminated most of the connections in the intake plumbing, I now suspect the turbo itself, either leaking air at the O-ring seal of the compressor housing or, worse, the shaft seal. I suspect the shaft seal because of the pressure in the crankcase blowing oil out of the breather.

Tomorrow I plan to connect the AFM directly to the throttle body, bypassing the turbo. If it fires and idles smoothly it will confirm my fears about the turbo shaft seal.

If the turbo is done I don't think I'll bother repairing it. The CT-20 is not the best thing Toyota ever made so I'll probably be in the market for a Garrett.

I'd appreciate any input, especially if anyone has heard of similar symptoms or experienced a failed seal.

Thanks, Bob

[Supra_devil]

I would check the seal, after a brainstorm i can't think of anything else that would cause all the problems you are having.

Instead of a garrett you could also look into a ct26b (mr2) and see how it compares to the ct-20, might be a good replacement.

i really wish i could help more but i don't know the 22r that well nor am i the best turbo guy around either.
hopefully mike speaks up on his expericances, may be insightful.

[celica83_gts]

Update- Bypassed the turbo, opened the wastegate, started 'er up and she purrs like a kitten. Kind of a good news/ bad news thing, at least I know where the problem is!

When I removed the piping this time there were fine aluminum particles in the oil, not enough to eat up my engine, but enough to say the turbo is toast. Catastrophic failure probably was not far off! I'll know more when I get the turbo off the engine.

Next week it's back to the beater for now. I don't know if my budget can absorb a turbo purchase this summer, I will shop around for deals. Silverstone Raymond sold me this one for a decent price, $250, and for the way I treated it I got my money's worth! If I can match that price I will be back on the road this year, if not I'll start fabbing a header to mount a T3/T4 hybrid for next spring.

Any leads on a reasonably priced CT-26 would be appreciated. Space is a concern as my manifold mounts the turbo downward, but it's an option I would consider.

All this probably puts my car out of the Sun Toyota show next month. Sorry Mike, I know it was kind of my idea, but I can attend in person and help out if needed.

[Supra_devil]

i'll keep my eyes open on ct's, as i replied in the other post i have multipe ct-26's sitting in the garage so you could see how one fits easily, i even have the stock elbow on one so that could be checked as well.

hope it works out for you man, later.