Can anyone help???

I have a 92 Legacy which keeps having some problems with the boost.

you could be driving along with no problems and then suddenly you loose all boost and then another 10 miles down the road it's working again [img]images/smilies/mad.gif[/img]

has anyone got any ideas to why this keeps happening?????????

please let me know

Thanks

 

I've also got a '92 Legacy turbo.

The boost on mine has been a bit strange during the last few weeks. It seems to be losing some boost (but not all) occasionally as it doesn't feel as strong as normal and stutters a bit. 10 seconds later it is back to its normal self.

This has only started since I had my SS exhaust fitted, although it has only happened 3 - 4 times. Is yours more regular than this? If it is I would imagine it would be v. annoying.

Mine is booked in for surgery on the 4th Jan so I'll see what the garage says (if you can wait that long).

 

How right you are, it can be very off putting.


If you are able to find out what it is please let me know as it is starting to do my head in [img]images/smilies/mad.gif[/img]

I'm not sure what it is called or what it does but i was not sure if it was something to do with the small cylinder thing in front of the left strutt with the tube going in to it top and bottom

I have also got another problem of when you have got your foot hard down in fourth and fifth it gives a cough at about 4500 rpm.

by the way, yes, mine is also running lumpy at the moment, it doesn't matter how hard or how gentle i drive it ???????

 

Could be the knock sensor picking up some det and cutting the boost thru the ECU and boost control valve.

Fuel OK??
Your SS exhaust might be giving you some more boost initially which then may have caused det.

Might be a good idea to fit a knock link or some det cans and have a listen.

Steve.

 

Thanks Steve

But if it was a sensor wouldn't it be all the time or at a set time??????

My problem is that it only happens at not set time

 

DG,

Not saying the sensor is faulty - but you may be just on the point of det so sometimes is does not cut the boost.But say the air temp starts to rise as you give it large then the det will be more pronounced and the knock sensor will do its job.

I have come across this on a number of imports running SUL of dubious quality. With the det cans on as soon as the det came in the boost was reduced to 0.5 bar.It recovered after a few minutes.

Also did once have a Legacy with noisy tappet which was tricking the sensor into thinking it was det.Is yours knocky??

Steve.

 

Yes,

So where do i find the knock sensor??

 

DG

Looking from the front of the car it is on the Right hand bank of cylinders,at the back of the engine (nearest to the bulkhead),to the left of the head/block joint i.e mounted on the block,underneath the grey Idle speed control valve (the one with ABC marked on it)It is black,circular with one M8 bolt thru the centre with one screened wire coming out of it.

Steve

 

Steve,

Mine is tappety - its the main reason its going in on the 4th.

What should I suggest to the garage to:
- Sort out the boost.
- Get rid of tappety noise (driving me mad).

Thanks,
Pete

 

Pete,

the tappety noise is a common problem on high mileage legacy's.

When I asked the dealer about this they suggested a very expensive rebuild, renewing all the lash adjusters (hydraulic tappets).

I have also heard a story about someone who had the work done only to find out the noise was due to a piston problem!

Before agreeing to anything I would simply try using engine flush and oil change and check for any change. I used to do a regular 3000 mile flush and change to keep mine in check. The noise is generally thought to be a lack of pressure on the adjusters either from a worn pump, poor oil, blocked galleries, worn ajusters etc.

There is a bit of reading on the subject if you do a search for 'lash adjusters' on the net.

Trying a few different oil types also may help.

Rich

 

Any idea how much the knock sensor is going to set me back?

by the way i seem to be looseing the boost all together now, it starts to boost up at about 3000 rpm and then at about 3200 rpm it just goes dull

any ideas