What did you do to your x40 today???

[gazO2V40T4]

Originally Posted by clarkey1984

I have made a video

I’d also try idle control valve

[clarkey1984]

Originally Posted by gazO2V40T4

I’d also try idle control valve

I have removed that and cleaned it out thoroughly, there was a fair amount of crud in there but it's now nice and clean and moves freely so I'm not sure, I think I'll re investigate the in tank filter again as there's bound to be more rubbish in there, although this time I'll remove as much fuel as possible out of the tank first and then clean it out using rag until it's totally clean and dry as well as cleaning the filter, then pour the fuel back in through the 190 micron funnel filter I got a while ago, that should remove everything else hanging around in the fuel, then I know for sure that side of things is perfect.

[gazO2V40T4]

Originally Posted by clarkey1984

I have removed that and cleaned it out thoroughly, there was a fair amount of crud in there but it's now nice and clean and moves freely so I'm not sure, I think I'll re investigate the in tank filter again as there's bound to be more rubbish in there, although this time I'll remove as much fuel as possible out of the tank first and then clean it out using rag until it's totally clean and dry as well as cleaning the filter, then pour the fuel back in through the 190 micron funnel filter I got a while ago, that should remove everything else hanging around in the fuel, then I know for sure that side of things is perfect.

Hopefully you get some results from that

Hopefully mine should be back on the road tomorrow as it’s in for retest all being well I’ll have to take it for a good old blast to blow out the cobwebs from it’s almost 2 year rest

[Antz]

Originally Posted by clarkey1984

I do find it odd how it'll sit there and chug like that for as long as I care to leave it, yet turning it off for 2 seconds and it idles fine again.

Mine does this exact same thing and I have no idea why. Ive replaced every sensor on the engine and fitted a MAC boost solenoid which made no difference. Changed all the vac lines for silicone ones, cleaned the MAF, tried a new MAF. Still does it.

I just live with it.

Does it effect your boost at all? Its not dropping into limp mode or anything and only boosting at 0.5 bar or such?

[canis]

Hmm.

I honestly don't know. I *think* I've seen faulty lambda sensors produce this effect, but it was ten years ago, and I wouldn't want to stake my life on it as I can't remember the exact symptoms. Have you checked the EMS light comes on during bulb test? Some sneaky person might have removed the bulb before selling it on.

Have you the technology to read engine codes? Presumably not, or you'd have done it already, but it might save you a lot of guesswork.

[Baffler]

When it starts hunting you could try spraying start gas or carb cleaner around all the vac lines joins, throttle body and IACV gaskets and monitor the idle.

Think I remember something else about the little inline one-way/non return valve failing between the throttle housing and the purge valve on top of the rad. Again, IIRC, there's a little arrow marking the direction of air flow on the valve so check to see the diaphragm is doing its job but be careful removing the hose as the plastic connections/barbs can be brittle.

[clarkey1984]

Cheers guys, I've not got Vida dice or anything, but it is on my to do list as it'll be very handy in general, and although I haven't tried it I doubt the generic gendan reader will work with it, my workmate tried it on his 2002 VW golf and it said lean condition bank 2.. on a 4 cylinder haha.

And no it still boosts fine, I'm not sure on bar as my gauge doesn't have bar on but it hits 10 psi at peak, although has always started to drop off very slightly once you reach about 4000 rpm, although I rarely take it much higher than that for any length of time as it pulls so well lower down there's not really any need to, and I'll try the carb cleaner idea to see if anything shows up

[aldred309uk]

Originally Posted by clarkey1984

It's done it on and off ever since I got it, adding the gauge hasn't changed anything, I do find it odd how it'll sit there and chug like that for as long as I care to leave it, yet turning it off for 2 seconds and it idles fine

Having watched a fair bit of roadkill (YouTube program of pratting around with cars) this does sound like it could be dirt in the fuel tank. Flakes of dirt and rust which are sloshing around in the tank become stuck to the fuel sock due to the suction of the pump and they can't get off the sock. When you turn the car off for two seconds the suction is removed and the flakes of dirt fall away from the sock which removes the restriction to the fuel flow and the car runs fine again.

You've already ascertained that the fuel tank has dirt in it so I would look here first before throwing parts and money at it. Hope this helps!

[V40T4R]

Originally Posted by Baffler

When it starts hunting you could try spraying start gas or carb cleaner around all the vac lines joins, throttle body and IACV gaskets and monitor the idle.

Think I remember something else about the little inline one-way/non return valve failing between the throttle housing and the purge valve on top of the rad. Again, IIRC, there's a little arrow marking the direction of air flow on the valve so check to see the diaphragm is doing its job but be careful removing the hose as the plastic connections/barbs can be brittle.

And they're two of this inline one-way valve, already changed them two as one was two-way playing up.

[gazO2V40T4]

Originally Posted by clarkey1984

Cheers guys, I've not got Vida dice or anything, but it is on my to do list as it'll be very handy in general, and although I haven't tried it I doubt the generic gendan reader will work with it, my workmate tried it on his 2002 VW golf and it said lean condition bank 2.. on a 4 cylinder haha.

And no it still boosts fine, I'm not sure on bar as my gauge doesn't have bar on but it hits 10 psi at peak, although has always started to drop off very slightly once you reach about 4000 rpm, although I rarely take it much higher than that for any length of time as it pulls so well lower down there's not really any need to, and I'll try the carb cleaner idea to see if anything shows up

Peak boost should be at 14psi and then tail off