and my dip stick guide was cracked too lol

MY ISSUE WAS WITH THE Z PIPE TINY SPLIT CAUSING OIL SPRAY AND PRESSURE LOSS SO SWAPPED THE PCV AT THE SAME TIME MY MPG AVERAGE IS ABOUT 21 lol shouting soz , i only do 4 mile each way for work so t expect crap mpg 40 plus on m62 etc

Picked up a PCV valve and dipstick tube yesterday, when I get chance I'll have a fiddle.

How hard was it to get the PCV valve to change, judging by what I've read it looks ball achey

Been a while since I changed one, but it's not too bad. On my old A31.8T Q it was really easy to get at. IIRC when I changed one on a Mkiv anni AUQ I undid the black plate (N249 etc )that attaches to the inlet manifold & just pulled it to the side, which gave better access.

Well heres the old dipstick guide. Doesn't seem cracked but I haven't cleaned it as you can. I had a little poke around. Didn't change the pcv valve as the t piece is sits in feels well brittle. Need the car tomorrow so I'll grab a new t piece before attempting it I think. Looks a pita due to the one use clips.

I also took a snap of the inlet pipe, looks wet and grimy to me, this comes straight of the PCV system through the hole on the left, I wonder if this isn't helping matters.

Picked up a new T piece which the PCV valve sits in today as mine is definately shot, the new one feels solid, the one on car is ready to crumble

I stripped the whole of my pcv system on Saturday, took about 3 hours from start to finish, though this included a lot of cleaning as all the pipes were full of yellow gunge (like mayonnaise), it also helps if you have small hands! My pcv pipe had a 2" split in it, generally the pcv valve doesn't need changing as it is a simple sprung plate, you can test it by blowing into it.

Since I've done this my economy has gone from approx. 25mpg to 34mpg, and it it some much quicker.

Small hands .....Fail

When you say PCV pipe was split, which one do you mean exactly ??

For future reference .....

The 'S' bend pipe that attaches to the PCV valve No 19 in the diagram. I purchased a silicon one from Creation Motorsport from e-bay, £20.00 including delivery.

The diagram doesn't relate to an AUM engine as the 'S' pipe connects directly to the inlet manifold on mine, whereas in the diagram it connects to another vac pipe.

Sorted the PCV valve and T piece. Fiddly but easy enough when get in too it. Hardest part was when my helper dropped a screwwdriver down under the passenger wheel arch (thanks Em)

But this is how the valve looked on removal, gave the pipes that i removed a clean out but not properly as I ran out of degreaser, bit of mayo lurking in them

Yuk never seen one that nasty before. Did you do the S pipe too?

Yuk never seen one that nasty before. Did you do the S pipe too?

Good innit, thought you would like that !!

The S pipe was done a few years back so no splits in it, I'm gonna have another crack at it at some point, I reackon the the the pipe that run into the block is munged up aswell, need more degreaser fist though, I'm going to do a MPG run into work in the morning, boost is still a little lower than expected but flat spot has dissappered.

Looks like that area is the solution them mate, if anything makes it better, keep at it.

MAF reading not looking to healthy !!!, thats from 2260 rpm up to 6000 rpm

Heres part of an old log I found from 2008 this only revs to 4960rpm, note the much higher MAF figures at lower revs

It's still not right, big boost drop Sunday third gear on a slip road, dropped back to 5 psi, Mpg still low.

Looking at these numbers it's pointing towards MAF plus possibly with added boost leak fun !!

Hi Dave, If it dropped down to 5psi that suggests it went into limp or you have an intermittent boost leak somewhere. Any fault codes logged?

Have tried running with the MAF unplugged yet?

Edited 6 February, 201313 yr by pauldazzle

I just unplugged it now, going to do a run to Pontypridd from town this afternoon, so I'll log it then too.

I think intermittent is the key word with this fault !!

I've been prodding around the vac lines and the stuff I can reach, but I think it's time to start digging into the boost pipes.

Oh yeah, still no codes !!

There's news !!!

After a bit of poking around on the inlet side of things I stuck my hand behind the seal area of the TIP after the DV and found this

Been down to TPS to enquire about a seal and they sold me this

Which looks the same colour as the gunk I found to me, so I think that seal has melted/rotted. So that will be swapped.

Also found this, which I've ordered new gaskets for !!

I wonder if this will cure the boost problem ????

Right BTTT !!

Boost leak ???

It's asking for a figure and not getting it between 2-3k rpm, then it levels out higher up

Does that make sense ???

After a few days faffing about on ramps etc, I'm still no nearer to finding out what the fugde is going on here.

Chacked and double checked pipe work, all looks solid, going to billys tomorrow to play sensor swaps to see if that throws anything up.

Worst part is ....still no codes !!!

Boost looks fine you will get a bit like that will never be spot on

Boost looks fine you will get a bit like that will never be spot on

What about the big gap at the lower end ??

Clive, is there anything else I can log regarding fueling or timing pull, did this one last night but not really sure what it means https://docs.google.com/file/d/0B1eiYmXOY7f0azNXamZrQmo1YWM/edit?usp=sharing