In the wet weather before the heavy snow the zed started hesitating and was low on power, i had just got a van for nowt off a mate and with all the people getting wet air-filters i just put it down to that and took it off the road for the winter, this afternoon i put a battery back on and fired it up, after pulling away i noticed the total lack of power again and turned back around, back home i pulled the nose panel off and checked the air filter, it was bone dry, checked the maf connection and terminals, all fine, and to eliminate the air filter from the list of possible problems i drove it up the street with the air filter off, still no power and holding back.

 

So..list of symptoms:

1)no power and feels like its holding back but not misfiring

2)revs hunting slighty at idle

3)if you blip the throttle once the exhaust has warmed up it pops as if its over fuelling heavily

4)coming straight into boost on light throttle as if they're having to compensate an air blockage or something

5)smoking heavily on over-run

6)sometimes it feels like its going to pull through the revs fine but when you open it up a bit more it just holds back and just makes the exhaust louder

7)havnt thought of 7 yet but am sure there will be something else!!

 

Now list of things i've checked/tried:

1)checked the air filter for dampness and even tried a short run without it

2)checked maf connection and terminals for corrosion

3)checked coilpacks and connections

4)checked boost hoses for any loose clips

5)it has bov's fitted so checked the block offs where the re-circs were fitted

6)checked vvt hadnt come loose and moved

 

Any ideas people??...

it sounds like you have an airleak and it's venting air somewhere...maybe one of the hoses to/from the intercoolers

 

best is to do a boostleak test

Hmmm had a mahooooosive leak when i first got the car where the re-circ block offs had blown out and it was nowhere near as bad as this, but good plan al get on it tomorrow as its wayyyy past drink-o'clock

how do u do a boost leak test,

Remove air filter and blow down the maf as hard as you can! :lol: seriously though av got no idea meself lol am just going to run it and listen for any hissing :lol:

pmsl, im sure its something like spraying all the pipes with wd40 or something

There must be a way of making a disc that can camp on the end of the maf that you can pop a valve through and pump up? : / just cant get me head round how to make the cap

There's a guide somewhere of how to make a boost leak tester out of the end of a drinks bottle and an tire valve off a bicycle inner tube - I'll have a quick look for the guide. Pretty sure you cut the end off the bottle where you'll have enough to clamp it round the pipe you're testing, cut the valve out of the inner tube and put it through where the screw top would have been - bit of sealant and there's your boost leak tester. I wouldn't put it through the end of the MAF though I'd at least test each side seperately - so pull the T shaped bit of pipe off and test each side of the T. Having said that my next step after what you'd already checked would be get the compression checked just to rule it out :) HTH

Edited February 6, 201114 yr by vern936

Hmmm thought about a compression check but its only done a couple of thousand miles since it had a "fully tested" engine fitted, not even hard miles either as its smoking like a barsteward on over-run which am putting down to pcv valves which SHOULD have been changed with the engine but "must have been overlooked" and am still waiting for them to be sent out to me, but even then they wouldnt cause it to use 2 litres of oil in a week :/

mine was was that, i disconected the temps sensor and it ran fine,give it a go you never know?

:biggrin:like lol

From the sounds of that mate I'd definately get a compression check done just as an indicator of whats going on in there. What colour is the over-run smoke?

the lid from a large jar of coffee (nescafe i think) then blag a tire valve from kwik fit or somewhere, drill the right sized hole in the lid, pop your valve in, remove maf, stick it in, tighten the jubilee clip, and pump some air in, listen for leaks, job done :)

Yea will try disconnecting the sensor tomorrow, over run smoke is blue, doubt its tubs as the inlet manifold is soaked in oil inside but the boost hoses are bone dry

I have a boost leak detector, and also conzult. Im off Thur night fri and sat if you want to pop over? Not an expert on conzult but we might be able to sus out the problem?

Thanks for the offer mate but think its sorted, will give it another run tomorrow to check but today i gave everything another check including the temp sensors and took it round the block again gradually going up through the revs, at first it was exactly the same but after 10-15 mins it cleared up so i tried a bit of loud pedal in second and it span the tyres up so all seems well? Is it possible that it DID have a wet air filter and had adjusted timing etc to try and cope then learned that it was dry again?