[Mk2] [Turbo] Horrific fuel consumption and low boost

[KyzarVS]

Hi Gurus

My Rev2 tubby has been off the road (garaged) for a couple of years. Have recently spent some time getting it back to tiptop again, but have the following issue:

Boost is limited - currently the best peak I've managed to get is .67 bar. It used to be .82-.86. Other than that the car actually runs smoothly.

Fuel consumption is awful - like 60km to a third of a tank awful (BP Super unleaded).

When I took the intake pipe off to get to the plugs, it stank of petrol. Also the plugs themselves were very wet. The rotor arm, dizzy and Magnecors all seem to be in good nick and because there's so much fuel, I was thinking it could be a sensor rather than a spark issue. What should I check? All the pipework is good, there are no air leaks. I was wondering if the symptoms could be casued by the lambda, but I don't know how to test.

TIA,

Joe

P.S. if it makes any difference:

Rev2 Tubby
Full turbo-back Tube-Torque bespoke exhaust with no cats
Mines ECU
Magnecor leads
Blitz boost guage / turbo timer

All mods have been on the car for years (I've owned the car for 7+)

[Charged]

If you've got a spare AFM, swap it over and see if that solves it.

[KyzarVS]

Not got a spare AFM - so took it off the top of the filter box and gave it a good clean - presumably I can test it for resistance across two of the output pins or something?

Put it all back together, changed the oil at the same time, gave it a quick spin - definately hesitant compared to how it should be (though my commuter is a 206HDi, so it's hard to notice as anything feels fast in comparison!).

Anyone selling a def good AFM cheap? Or could lend me one for a weekend?

Joe

[Charged]

Is it better than it was before you cleaned the AFM? Or the same?

[KyzarVS]

Difficult to say as I changed out old oil at the same time... doh.

Under no load the engine revs really cleanly. Seemed very good to start with once warmed up, but noticable under load (full throttle @ 1500rpm in third) that it's struggling to burn it all. Overall I'd say it's smoother thanks to the new oil, but the same as far as over-fuelling. The AFM actually seemed in good shape - the flap moves freely and the hinge doesn't seem worn or anything.

It's always run fairly rich (don't they all?) - but never like this. I'm tempted to say lamda or AFM - but I'd rather diagnose than just throw money at it. I'll have a prod around with the multi-meter this afternoon and see if I can figure out a way of testing the AFM and lamda...

Joe

[Charged]

Sounds like you given the AFM a good enough check.. I had similar problems on a REV2 Turbo engine and it was all down to a sticky flap. swapped it over for a newish AFM and was all good.

Have you pulled the fault codes?

[nikaiyo]

Have you checked your timing?