farcrygamer

Thank you so much for helping out with this. That was the very scenario i've got in my octy. The carbon can drains breather was badly blocked as the pump managed to apply vacuum with n80 open. I got a new carbon can from the stealers. The old can was much heavier than the new one. I replaced it with the new one, cleared the codes and voila. so far so good. The car pulls way stronger now and the liveliness is fully restored. The MPG also raised from 30-32 to 34-35. You really do know the stuff - Top Man! Thanks a ton again.

Yes, That is correct. the hand pump can blow through the vent line from the engine bay and suck through it without creation of vacuum with or without the gas cap on. the vent line from the tank to the engine bay looks as good as new underneath the car with no cracks or and split points. garage guys couldn't suggest anything apart from what i've already done. they think it's the carbon canister itself that is creating a problem although it can hold pressure. Do you agree with that? any further suggestion? Cheers

looks good to me. i don not think you will need a power gloss anywhere as you got a quite new car. AG glass polish can be applied by both hand or machine. it is more of an in depth cleaner then of an abrasive polish. if you decide to do it by DA i would go for a firmer pad not the finishing one. it wont cause marring on glass. good luck

Just a little update on the case :-) Here are my findings so far : I will go to this garage this evening to fit a high flow cat, and 2.5'' jetex exhaust as the existing factory fitted one is really knackered. hope to get some additional findings about this 16825 trouble. Thanks

My wife used to have a psi motorsport box in her audi a6 tdi pd 130 (very similar engine to fabia vrs) and the overall experience was really good. we rolling roaded it at cox develpments in reading and it went up to 162 bhp. serious improvement taking in account that i got the box on ebay for 21 quid inc postage. MPG was prety much unaffected, maybe very slightly improved. there was no additional smoke. the car never missed a beat and never thrown any fault codes in 30000 miles (from aprox 130000 to 160000) we covered with the box fitted. treed a few boxes in the car that she now has (2003 bmw 320d) including dragon, speedhawk, p-torque and racechip. by far the best was the p-torque one. serious power improovement and very smooth ride. no fault codes, no smoke, no trouble. others either gave either little power gains, or thrown codes (rail pressure etc...). a good friend of mine has covered nearly 100000 with spider box in his nissan navara and it's doing great. i also know a few people that were having problems with cheap boxes. although higher end tuning boxes can be quite good my personal opinion is that remap is all the way to go if you want to keep the car longer.just wanted to share my experience about tuning boxes.

Thank you so much for such a great spet by step guide. I'll try to do the tests and hopefully post back with great news. i got 3 fuel caps all together so at least one will be good i hope. one is nearly new fitted last year, one is my old cap and one is a leftover from a mates golf gti. i tried them all so far with not much luck. will try with mityvac tomorrow in a garage and see what it discovers :-) Cheers

there used to be a few great guides for hoses fitting on here and on uk-mkivs.

depends on what hoses you want to fit in particular. turbo inlet pipe can be a bit tricky as it 's very tight space to work in. other pressure hoses are quite easy in my experience.

in such case it really shouldn't be an issue. enjoy the bone-shaker ride :-)

I really tried to smell petrol around the canister area buti simply couldn't. The canister cap was also replaced last year together with the pcv system and boost hoses. No hissing definitely when i open the tank. fuel trims also seem fine by vcds logging. the vent line i i suppose the one that goes from the fuel tank all the way to the engine bay and into the carbon canister, isn't it? and i also suppose the seal you mentioned should be the seal on a carbon can. On friday will go to a local friendly garage who will let me lift up the car and inspect the fuel tank vent lines so i really hope to find the root cause of this ultra annoying problem. is there any test for the canister seal? i don't really fancy buying a new canister and still have the same bloody code on :-) . thanks a ton for helping me out with this

yes, very harsh in my experience. i got koni street kit shocks and springs and powerflex-ed every single bush in a car. it improves the maneuverability a lot but subtracted all the smoothness that my car used to have.

I got powerflex on the front and back of the dogbone mount and it's very harsh for already 30k. it never really settled to a smooth oem feel. of course power delivery is way better.

the n80 was replaced in oct 2008 but the car has covered less than 20k since then. i checked the n80 yesterday and it ticks fine when warm. t-body was cleaned, the whole pcv system and all pressure hoses were replaced with silicone ones last summer (less than 10k back). I don't know yet where that n115 is. After i clear the codes with VCDS and allign the t-body the cars restores the power and gets fairly fast again. but after a while the code appear again and the car gets a little more sluggish (still not slow at all but not as responsive as it should be).

powerflex will make your rear end very harsh in my experience. if i was you i'd consider leon cupra r bushes instead.

The N80 (valve on top of the canister itslef) is been replaced so it shouldn't be problematic. the pipework between the tank breathing and the throttle body look ok, throttle body has been cleaned, seal replaced and properly torqued. the canister ticks when the car is warming up but it does not tick when the engine is at optimal temp as far as i noticed. i do not know where the n115 is? could you guys suggest what valve is that one and where is it?