Second turbo problems (still!)

Hi guys,

Some of you may recall a while ago that I was having problems with my 2nd turbo not boosting at all, following a rebuild. The garage that fitted the turbos again 'enlightened' me that there was in fact a wastegate for each turbo. I was pretty sure that there was only one wastegate and the other wastegate looking thingy was for the exhaust gasses. (You've probably guessed by this point, I am not mechanically minded.)

This had me worried that it's plumbed in wrong. I was comparing it to a stock TT today and I couldn't spot any noticeable differences (Although I was unable to check the actuator that sits at the very back of the engine, all hidden away etc.) - normally, I'd take it back there, but this garage is at the other end of the country (long story.)

I've studied the 'sequential system explained' posts on here and to me, it seems like everything should be working just fine. I put my car in to the '5 minute TTC mode' that's supposed to help diagnose faults, but I still can't get anything from it. It boosts to 0.6 bar, then just tails off as revs raise. I've attached a picture to show the new 'map' of my engine bay and I was wondering if anybody could spot anything that may be causing this issue. Prior to the TTC mod I didn't get any rush, or even blip on the boost gauge at 4000 RPM, no 'switchover' sounds or anything. Post TTC mod, I still get cack boost.

Cheers guys

IIRC the stock turbo's have internal wastegates, the actuator you can see down underneath the turbo's is the EGCV.

Have you checked the pressure tank? I remember a similar problem with mine was caused by a pipe popping off the vsv for wastegate valve. I could only get 0.6 bar and no tubby 2.

IIRC the stock turbo's have internal wastegates, the actuator you can see down underneath the turbo's is the EGCV.

 

Have you checked the pressure tank? I remember a similar problem with mine was caused by a pipe popping off the vsv for wastegate valve. I could only get 0.6 bar and no tubby 2.

Checked it in what way? The pressure tank is the only part of the bay which hasn't had fresh vac hoses put on (Only because I ran out ) which may actually be causing this!

Aha, may have solved it! The little actuator looking widget at the very back of the engine bay only had one hose coming off it. Alas, my hands can't fit down to plug another hose on without dismantling a few bits first, so I'll get that done this evening.

From the map, that's the Exhaust Gas Bypass valve which is not plugged in correctly. It's the hose that the blue arrow is pointing at. Assuming that's disconnected, does anybody know if that would cause the problems that I'm describing?

That actuator MUST have bothy hoses to it. For testing put the hoses back exactly as stock, and forget the boost controller. Go from there. The two hoses to the rear actuator connect to the same canister, if one is off the canister is vented to atmosphere. You would have no effective second turbo if that pipe was off. it's worth buying some VERY long handled needle nosed pliers for getting those hoses back on. They are very useful for many other things. Mine have handles about 15 or so inches long.

That actuator MUST have bothy hoses to it. For testing put the hoses back exactly as stock, and forget the boost controller. Go from there. The two hoses to the rear actuator connect to the same canister, if one is off the canister is vented to atmosphere. You would have no effective second turbo if that pipe was off. it's worth buying some VERY long handled needle nosed pliers for getting those hoses back on. They are very useful for many other things. Mine have handles about 15 or so inches long.

I've just discovered I can about fit my hands down there for it. I've plumbed it back to stock (bypassing the EBC) and plan to reconnect that hose soon - it appears it hasn't been connected since the start of my woes, which explains a lot!

Going to wait until my flatmate returns with his toolkit so I can set about removing a few of the pipes in the way to pop on a vac hose.

For testing if you can push it on easier without the clip, it should stay put OK. Or smear a bit of oil on the inside of the hose and the metal nipple of the canister if you try and push it on WITH the clip on. Opening the clip AND trying to push it on will be tricky and you might split the pipe or damage the stub where it joins the canister... Then you are in trouble.

nipple ... lol

Just re plumbed this the other day it takes a while but you can make it a far less easier task by removing the turbo pipes... It's not a difficult job just time consuming and for the love of god use genuine rubber hoses no silly silicone.

Tip:boil some water and dip the ends of the hose in it makes it easier to put them on

Not to fear, I have hands like a Japanese woman it seems. I was able to wriggle my hands behind the turbos and under the pipes etc. and got the pipe back on. Running stable, stock boost now, the car feels much faster. Time to pop the EBC back on and get her back to normal

Sounds like you'd make a great pick pocket

Sounds like you'd make a great pick pocket

I'll add it to my CV