Last couple of days ive notjced my car is down on power, normaly reaches 1.5bar boost but will now peak at 1.2.

Doesnt feel as lively and lacks the punch. No eml but know something is off

Any ideas,?

As stated in many other topics, MAF, coilpacks, spark plugs, split pipes, N75 valve.

Check the above.

Not sure what that was all about but its all now, just given the maff a good cleaning, that was pretty dirty

Check vacuum, breather and boost pipes/hoses

Thought id update this, it has got worse, only bosts to about 1.3 bar max now where before it was ok sometime and not others, swaped in a new n75 and although this seem to sort out one issue it hasnt helped with tje boost

Cant find any air leaks, its possible maf is on the way out or possibky map

Wll update gonna see if i can find fault codes

While engine was off i unplugged the MAF and took it for a drive just now, exactly the same, no change in the way the car drove and same boost reading, id had thought recently i wasnt getting as good mpg

Faulty MAF?

Got p0102 powertrain

mas air flow circuit low input

That code would log if you drove car with maf disconnected, did you clear it, drive car and check again?.

Yea th8e came up when i scanned it a few weeks ago but my mate cleared them before we checked what they were, i knew i haf an problem with SAI pip broken but didnt realise it brought up a seconf fault code which my mate sent to me yesterday as he saved it

A silly thing to overlook but then neither of us are clued up lol

New maf hs made no difference, something odd going on here

Ecu need reseting?

Mileage ???

130k mate

remaped mk1 octy vrs

Coil packs? Spark plugs? Got those checked?

Fuel filter changed recently ??

Checked spk plugs and all seems well there

How do yoi check coil pqcks? When they have gone in the past for me it would run on 3 cylinders

Not changed fuel filter though

Well coil packs can cause problems and not missfire. Try to find some swaps and have a go.

That code brings up this - http://wiki.ross-tech.com/wiki/index.php/16486/P0102/000258

 

When you say new maf, was this a bosch/skoda unit, or an aftermarket/ebay one?.

 

Aftermarket units have been known to be faulty "out of the box". Has your mate done any logging runs to see what the maf is actually doing?, is he using VCDS to scan?.

That code brings up this - http://wiki.ross-tech.com/wiki/index.php/16486/P0102/000258

When you say new maf, was this a bosch/skoda unit, or an aftermarket/ebay one?.

Aftermarket units have been known to be faulty "out of the box". Has your mate done any logging runs to see what the maf is actually doing?, is he using VCDS to scan?.

This was a scan done a few weeks ago when my sai system chucked an eml light so he cleared it

Ive just done an ecu reset and i 'think' thats done the trick and am now getting higher boost similar to before

Im also thinking i wqs overboosting though as it wouod go past 1.5 bar and now peaks abround 1.4 - 1.5 bar depending on what gear im in

That said goi g to heqd down to cntuning at weekend for full proper check over!

does anyone know what the boost should be on a standard vrs 

9-10 psi approx

my car is doing the exact same thing, drives fine but no boost, but it is an intermittent fault. it did it awhile ago and I changed a suspect coil pack and its was fine for a while, but it did it again today.

Ive since taken my cat to cn tuning, after i teplaced the maf i still had fault codes for it so he cleared that, and they havent come back since and the car has been loads better but have taken my boost guage off as it was connected at fpr line.

Also tonight i bypassed the n249 valve and wow, what a difference, feels stronger than ever and spools up a little faster

9-10 psi approx

thats great thanks