31 replies to this topic

[hawks_123]

Having another problem with the B4 at the moment Drives fine till about 3500rpm then once changeover starts car will sometimes surge. If it doesn't surge then power drops as if ECV is opening. But the kick from the secondary never comes on. Max Psi is between 6 and 10. Lower than normal. We've tried quite a few things and found nothing. We have a laptop and are monitoring the ECU live as we drive, but we don't know exactly what to look for, if anyone does please let me know. Any suggestions at all would be appreciated Thanks Guys

[buzzda]

A blind man's stab in the dark... the pressure release valve on the 2ndry? (the grey plastic thing that goes back into the intake)

[Jimbo]

Run a boost guage of the vac line that comes off the connection to the secondary BOV ( NOT the secondary BOV vac line itself ) this way you can moniter exactly what the ECV is doing and if the secondary is actually making boost.

[hawks_123]

I got it back from the mechanic yesterday, but there were a couple of leaks. With them fixed i get another couple of psi, sits dead on 8. But there is definetly no change over onto secondary. And it does seem to be pinging very easily, doesn't even need to be hot. Any ideas?

[Delete This Account]

Needs a tune asap! Will fix all your problems Mine was doing something weird the other day when it was 45 degrees, changed over to secondary at 4000rpm instead of 4500

[RX25SE]

I know SFA about TTs but I think this issue needs to be addressed BEFORE a tune. I read somewhere that these things have some sort of solenoid box thats driven by the ECU and controls the turbos by vacuum? Cracks leaks in the hoses? Hoses blocked with carbon/oil residue?

[buzzda]

In limp/safe mode?? +1 for the tune, ours used to ping and go into limp mode all the time if it was anything over bout 26deg. Since tune- no limp mode, no faults, no ping. 41 deg other day A/C cranking (of course), it was boostin like a trooper.

[Delete This Account]

I've heard of this "limp mode" What is it? Is it pretty noticeable? Any warning signs or lights to say it's in limp mode? lol

[buzzda]

I've heard of this "limp mode"

What is it? Is it pretty noticeable? Any warning signs or lights to say it's in limp mode? lol

It's when the car is bein a pussy.

Warning sign = right foot goes to the floor.... start yellin.... "WTF! COME ON YOU SLUT! FUCKEN GO YOU CUNT OF A THING!"

[Delete This Account]

It's when the car is bein a pussy.

Warning sign = right foot goes to the floor.... start yellin.... "WTF! COME ON YOU SLUT! FUCKEN GO YOU CUNT OF A THING!"

Shit, My girlfriends car must be in limp mode all the time lol

[Mosti]

Shit, My girlfriends car must be in limp mode all the time lol

In limp mode the car will not boost over 7-8 PSI

[robt]

I agree with it being the secondary BOV. It needs to work so the secondary and spool up before the valve in the intercooler opens up. If it is not working, as I have discovered by removing it, no matter how har you rev it it will not boost properly, just rev. Check its operation or borrow one. Remember that it works in reverse to a normal BOV.
Either that or do a full ECU reset. You know black to black, green to green and follow the instructions.

ECU reset link

[hawks_123]

Needs a tune asap! Will fix all your problems

Mine was doing something weird the other day when it was 45 degrees, changed over to secondary at 4000rpm instead of 4500

A tune would be great, can't see the point in doing it when there could be a mechanical problem.

[Alex]

It could be a whole host of things. Jock had the same symptoms on his old GT TT, turned out to be the secondary being cactus and seized. Without sounding too cliche... Start considering ditching the twins. There's only so much money you'll pour in, for reliability's sake, before you fold in, and just ditch one.

[RX25SE]

I've heard of this "limp mode"

What is it? Is it pretty noticeable? Any warning signs or lights to say it's in limp mode? lol

Limp home mode is normally a preset 'safe' tune to get you home without damaging the engine.
It will normally activate when the ECU sees data it cant understand or data it knows to be unsafe.

In modern cars it will activate when 'emission non compliance' is detected. It will activate the MIL (Malfunction Indicator Lamp) and may only allow 5 engine starts until the ECU sets the max engine rpm to 3500 and locks the trans in top gear, to force the owner to get it fixed.

Sorry to the OP for off topic!

[hawks_123]

Well just put the stock top mount cooler back on. Still having issues. Flat out in first boost goes to about 10 or 11, at about 5500rpm there is a massive drop in power and then another kick as if going onto secondary, but by then it's time to change gear. Pretty much does the same in other gears. Anyone else had this problem before?

[hawks_123]

We had a laptop hooked up to the car while we were driving. according to the PC there is 2 wastgates (i thought there was only on?) and they were opening and closing under power. This sounds odd to me, but a B4 is an odd car. Is this normal. Also does wastegate chatter sound a bit like pinging?

[buzzda]

There is only one wastegate - on the primary. It should open at the start of change-over and stay open. There is a "Relief Valve" on the secondry that bleeds any boost off the secondry as its spooling back into the intake track. It should open during change-over then stay closed after.

This may help

Wastegate chatter does sound a bit like pinging (some mistake it for pinging).

[RX25SE]

This may help

Great read Buzz.

[XXB4XX]

Sorry to be the prick here.. But sounds like it's actual turbo issues.. Nothing to do with the tune, it's a hardware failure somewhere.. Check all the vacuum lines as they activate the changeover etc.. Or check the actual 2nd turbo itself!