Turbo + Catalytic Converter
 

Okay, well, this might sound dumb, but my recently posted problem might have something to do with my catalytic converter being gutted. So, I ordered a magnaflow converter to replace it.

As far as I know Toyotas don't require back pressure, but as soon as I gutted that converter the turbo went all beserk and yeah. Does the turbo need the catalytic converter? or what?

A lot of people dont have them but it is only required if you have to pass emissions.. If so you may need a high flow cat. Mine has one but it also needed to pass emissions where the cars last home was.
I am not sure if i will take mine out it seems to not have any issues. If i were you i would just take it out or put the gutted unit back in

Contrary to popular belief no 4-stroke engine "needs" back pressure, for reasons which I'm not going to bother going into lest I open a whole nasty can of worms...

Anyway, all I'm saying is that removing or gutting a cat should have no effect on your turbo's operation. For the benefit of people who haven't seen your other thread, what is the actual problem you're having? Lack of power?

If so (and I'm guessing you gutted the cat because it was damaged already?) the escaped material from inside the convertor may be blocking the exhaust further down, it usually gets trapped in the back box. Pulling the whole system off & cleaning it out is the solution to this (or ideally replacement).

Let us know what the actual problem is if not that & I'll have another stab at it.

I agree :bigthumb:check the back Box and see if your missing converter pieces reside inside

Never mind, I found the thread & linked it now...

http://www.toyota-supra.info/forums/...o-problem.html

So from what you're saying the boost is going through the roof & then the motor cuts out until it drops off? (known as fuel cut, designed to save the engine in case of a stuck wastegate)

If so then yes, you could have a stuck 'gate but as you say it happened after you gutted the cat you may have damaged/dislodged the actuator pipe or rod whilst working on the exhaust. Look at the bottom of the compressor housing under the intake pipe fitting & you'll see a small diameter (1/2") hose going from the turbo outlet to the wastegate actuator, check this is not split (for what it's worth change it anyway) and is securely clipped on at both ends.

If it is OK then you can do a simple check to see if the actuator is working or not. Apply (using a bicycle pump or similar with a gauge) no more than about 10psi to the actuator. The rod should start to move at about 7psi. I can't stress enough NO MORE than 10psi by the way... (actually the tsrm says 11.4 but hey...)

OK, so if you've done this & the rod IS moving as it should then all I can think of is you may have bent the actuator rod while working on the 'zorst... Either way make sure you fit a good bit of hose to the actuator & clip it on securely & then see if it's cured before spending out on parts you may not need.

Damn I'm crap at describing how to do stuff, hopefully this helps & you can get sorted without spending out again...

You explained it fine MA70. I thought we'd already gone over this in another thread.

Cyto, a missing cat will not cause any problems... a clogged one will! At this age it's not uncommon at all for a cat to be clogged.

Just an FYI for the benefit of the group - When a cat gets clogged it is usually due to certain chemicals building up and glazing on the catalyst (it's not really something you can clean off). However, it is always worth checking to see if a blockage is actually due to loose debris collecting in front of the catalyst... this can be cleaned out by back flushing the cat with pressurized air (do not spray the catalyst directly with a high pressure blower though, the honeycomb is fragile).

Backpressure is garbage... BUT too large of an exhaust DOES have negative effects on N/A engines and *some* forced induction systems. I'm not going to go into it. The temperature bump exhaust gasses see while passing through a cat make up for what restriction is presented by a *decently flowing* cat. There is no reason not to run a cat other than just being a cheap SOB... if you're concerned about pressure get a high flow cat; it's less headache come emission time and less polution (if you're on of those wackos who doesn't believe humans can create enough polution to cause ecological problems try driving through any major city on a day with low barometric pressure.... F#$%ing idiots...).

I ordered a cheapo Cat, and I've heard from 2 people that the wastegate is stuck. What do I need to buy? Any links of the EXACT part?
And thank you all for the support!

The car does already have a straight pipe out the back, but the Cat was destroyed during the overheating that caused the BHG.

Water got in the Cat and melted everything, he gutted the whole thing and put it back on there.

You need to TEST the waste gate... don't just throw money at the car or you'll be broke in no time.

We have, we took the little tube that connects to the actuator, put a ton of pressure and nothing happened.

2 different people suggested it was stuck shut.

I have been meaning to replace it for a few months now, but I havent known exactly which part I needed to replace.
Is this the right part?

http://www.ioffer.com/i/Toyota-CT26-...urbo-124287115

Yeah, I was one of the people who suggested it... or was that someone else's post I responded to... doesn't matter anyway, just wanted to be sure you tested it.

That looks like the right part, but I would ask the the distance from the center of the two mounting holes from each other and the distance from the center of each hole to the center of the bell... just to be 100% sure.

If the gate itself is stuck a new actuator isn't going to help. You'll need to pull the turbo and see what needs cleaned up. You may want to disconnect the actuator's arm and then try moving the waste gate's armature by hand or with pliers. If the waste gate itself is stuck it is possible te actuator is also damaged now as well, so re-test it when it's disconnected.

Okay, I'll do that. It's almost 10 degrees outside, so I'll wait until tomorrow.
Thanks for all your help. I'm starting to get an understanding of this problematic car. So many things can go wrong. Its crazy.

tsrm http://www.cygnusx1.net/Supra/Librar....aspx?S=IN&P=1

(if you haven't already got it in your favourites, PUT IT THERE!!! It's a godsend!)

In the tsrm it says if the wastegate itself is stuck, buy a new turbo! :roflwtf:

OK, back to planet earth & most stuck 'gates can be freed by oiling the pivot & working back & forth with pliers (actuator disconnected at this stage) until it's nice & easy to move again.

A lot of turbos can be got to without removal but the CT26 is a bitch to get at in the Supra (ask my knuckles!) so you'd be best off removing it if that's the issue. As cre said, if the 'gate is siezed the actuator may have been damaged by now but considering the price of new ones it's worth testing while disconnected to make sure. Not with "a ton of pressure" though as this can damage it, just around 10/11psi as in my previous post & it should move at around 7...

Don't rely on oil to lubricate the waste gate... it's WAY too hot in there and no oil will last. Use a HIGH QUALITY penetrant to CLEAN our the hinged. Work the hell out of the hinge while keeping it thoroughly saturated and periodically flush it out with more.

I hadn't realized that OEM CT-26 waste gate actuators could be had as inexpensively and the OP found... last one I had to replace was for a monster Turbonetics and ran about $150, IIRC.

Oops, I meant pen. oil!!! Actually brake cleaner would be a better bet wouldn't it? Bearing in mind it's not going to leave behind any residue to burn into carbon & stick it again?

That actuator isn't bad at all, does it specify it as a Supra one though? The Landcruiser & others also used the CT26 & ran different boost levels IIRC...

Well it was the wastegate actuator.

We pumped over 120psi into mine and it wouldn't budge. Thanks to cre, I now am good to go. Although, I still have a code 52 and 2 I think? Maybe 12. I'll go test in a minute lol.

Thanks everyone!!!

Sorry for the gap here... we've been working this out via email.

The actuator Cyto found is not for a MKIII... probably a MR-2 (doesn't look like the LandCruiser's actuator).

Get that code 52 taken car of... you'll be amazed at how crippling that one is.

Is it easy to fix? Where's that guide you told me about?

Oh... my apologies; I had forgotten.

Easy? Well, yes and no. The sensors are not easy to reach but you can manage as you only need to disconnect the clips and pull them out far enough to cut them from the harness with a couple inches of extra wire... well, you'll see.

http://www.supras.com/06/techcenter/display.php?QID=69

This is the most common fix for a code 52. If this doesn't fix it the issue is most likely a damaged knock sensor (GTEs have two).



NOTE: Do be careful when working around or directly with the knock sensors. The plastic housing is often a bit brittle from age and the internal element itself is piezoelectric and delicate.