SiofChester

iTrader: (2)

Hi Folks,

great forum you've got here - lots of useful info in here

I've got a minor hesitation problem with my new MY00 Turbo 2000 - it holds back (not enough for a missfire) on full boost in 3rd and in all gears, it's not a smooth linear boost, more of a twin-turbo effect with the turbo kicking in around 2k then a boost full more power at about 5k.

The car's got a shed load of service history and has just had the plugs and air flow meter changed and the fuel filter looks almost new so i'm slightly confused as to what could be wrong.

I dont have a boost gauge (yet) so I can't see what it's boosting to...

Any ideas as to what's wrong?

motorola222

in a normal circumstance id say maf sensor but u cud have vacuum leak too.

Mrchips

iTrader: (7)

AS above, leak or turbo actuator maybe.

SiofChester

iTrader: (2)

Thanks folks, what's the best way of checking for a leak - is there a particular place that hoses seems to split?

prodrive.greeny

iTrader: (3)

Did you sort the problem out mate? I have the identical spec car and buggered in trying to find solution.

After reading through loads of threads there's 3 main potential causes;

1) BOV
2) Decat fitted on a ppp mapped ECU
3) Coil packs

I've tried for air/boost leaks and MAF and all fine.

SiofChester

iTrader: (2)

I've thought of the BOV too but aint sure how to test it...

I've no decat or PPP ECU so it's not that. My money's still on the lambda sensor but I cant find one for under 50 quid second hand, and they are only 75 brand new!

chrisdicko

iTrader: (21)

To test the BOV you could try removing it, and blocking up all the holes.

Don't run for long like this, as dependant on your turbo you will **** it up, but a short blast will see if that is the problem or not.

c_maguire

You can save that £75, the o2 sensor signal is not used by the ecu when hard driving. Symptoms of a faulty o2 sensor are poor idling and surging on a constant throttle etc.
I presume your problem existed before the plugs were changed? If not, too large a gap on the plugs can cause your symptoms, 0.7mm is good.
You could in the first instance clean the boost solenoid as they can get oil contaminated over time and start sticking.
The coil pack someone else mentioned was an issue on earlier cars with separate coils but not on yours which if a 1999-2000 car has one coil pack for all four cylinders. On your car the leads could be a possibility due to age.

Kevin

prodrive.greeny

iTrader: (3)

Mines had a new o2 sensor and obviously not worked. Either the MAF or BOV. How do you blank it off?? I might just try removing it and cleaning it up with carb cleaner and refit. Hmmm

chrisdicko

iTrader: (21)

Put a bolt in to the Vac pipe, then cover the hole in the inter cooler where the BOV was.

prodrive.greeny

iTrader: (3)

Well it's not the plug gap. The standard size gap NGK produce on the PFR6B is between 0.7 and 0.8mm

SiofChester

iTrader: (2)

Them's exactly my symptoms - light constant throttle gives a surging at a frequency of about one per second

prodrive.greeny

iTrader: (3)

^ ^ ^ ^ well i have a reciept from Subaru in my service history of this being replaced 2 years ago, yet i'm still showing the symptoms of splutter on boost

SiofChester

iTrader: (2)

If yours is on boost, I'd put money on it being the plugs. I had this problem but new plugs from ebay solved it. Only cost about a fiver for the 4 of them but took about an hour to fit them

prodrive.greeny

iTrader: (3)

I've did mine the other week and still the same probs!

I'm left with potentially

1) MAF - did the CEL test and got error code 23. (just priced at £189 from Subaru)
2) Coilpack
3) BOV

c_maguire

Your original post says the car is hesitating under full boost, no mention of cruising on a constant throttle.

Kevin

prodrive.greeny

iTrader: (3)

Do the CEL check mate where you connect the 2 black connectors under the steering column. If it shows 2 long and 3 short 'engine check' flashes on your dash then you have error code 23 which means the MAF is dying (someone please confirm).

prodrive.greeny

iTrader: (3)

Right mate as i'm in the same situation i've been at mine non stop since i finished work as its doing my nut in.

Stripped off the intercooler to cheakc all pipework - all fine.
Stripped down MAF and gave it a clean.
Removed BOV and sent it to Baileys for a refurb, should get it sometime next week (40 quid).

I think i may have cracked it though when re-asembling the airbox. I noticed on several occasions that the top half of the airbox wasn't clipped in flush with the bottom and as i'm new to scoobs i thought it was just missing a couple clips towards the bottom half. However i was clearly being a dunce because the top half of the airbox simply slots into place with locating slots and then is finally secured by 2 of the metal clips/straps.

So basically go check out your airbox and see if its properly on?? Just a thought. I can't tell whether its solved the problem though as the intercooler has a gaping hole in after removing and sending off the Baileys. DOH!