1.8T not running right, hissing but no leaks?

[kirkmiles]

I have a 1.8T AUQ with Revo stg2 map, dont think its been running right for a while as i drove my mates Revo stg2 and was like a different beast :-( It just doesnt seem smooth and sort of bogs down mostly coming on to boost. Just doesnt feel nice to drive. Somtimes it feels as if ive dipped the clutch and just cuts and off again. I have connected a fuel pressure gauge inline and is showing 3.5 Bar rising to 4bar when vac line off FPR. So far i have changed --- MAF(less than 12 months old genuine from ECP) - CTS(Genuine few months old)- N75 (Genuine)- 2.0 TFSI coils- Full coilpack loom- Injector seats -----I have made a boost leak tester and found some leaks, Injector seats and pancake pipe which ive now sorted(I think). No longer hear any hissing when pressurised to around 15PSI. When driving the car, if i drop my right foot i can hear the turbo whistle but also a hissing sound? What could this be? I have VCDS and a boost leak tester so if anyone has any tests i can do it would be much appreciated

 

[Westy]

Check TIP, rubber charge hose, and DV. Also has your car ever run right since you bought it or have you always been chasing issues?

 

[kirkmiles]

Surely if there was any leaks from the TIP or any hoses i would hear when doing the boost leak test? I dont think its been running right for a good while now just want it sorted now. If i cant sort shortly think i will be having a trip to awesome but its over 2hrs away so want to avoid if poss. Could it be a cracked manifold or loose turbo?

 

[Broken Byzan]

pcv pipes goosed.

 

[Westy]

Surely if there was any leaks from the TIP or any hoses i would hear when doing the boost leak test? I dont think its been running right for a good while now just want it sorted now. If i cant sort shortly think i will be having a trip to awesome but its over 2hrs away so want to avoid if poss. Could it be a cracked manifold or loose turbo?

It depends where you do the test from. Most do a pressure test from the throttle body hose to the charge pipe but this is only good for intercooler testing. If you are testing through the turbo then ignore my last post.

I had a cracked turbo that caused a fluttering noise on first couple of spool ups when cold but no hissing. Might be worth buying some silicone hose and replacing as much of the rubber stuff as you can.

 

[kirkmiles]

pcv pipes goosed.

Which ones? I have a catch can so dont have the usual suspects, they have been binned

 

[kirkmiles]

It depends where you do the test from. Most do a pressure test from the throttle body hose to the charge pipe but this is only good for intercooler testing. If you are testing through the turbo then ignore my last post.I had a cracked turbo that caused a fluttering noise on first couple of spool ups when cold but no hissing. Might be worth buying some silicone hose and replacing as much of the rubber stuff as you can.

Yes tested from the TIP right through mate. I sometimes get lil bit of chatter but not often. I have removed SAI,N249, N112 and EVAP. All boost/Vac hoses are silicone apart from N75-actuator hose.

 

[kirkmiles]

Anyone else? Please help

 

[<tuffty/>]

I would suggest logging... at least blocks 003,020 and 115 initially... see whats causing the cut...

<tuffty/>

 

[kirkmiles]

I would suggest logging... at least blocks 003,020 and 115 initially... see whats causing the cut...

Will do mate, its strange it seems to do it more on part throttle than WOT. I will post some logs and see if anyone can spot any issues. Thanks