Do i have a boost leak in my intercooler pipes?

DJ_Troopa

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What's the symptoms for a boost leak in IC pipes?

Ever since my car came back from the garage after it's bottom end rebuild it sometimes stutters on start up for a second and then idles normally.

On very hot days the outside temp on my display reads 5-7 degrees more than what it actually is outside. I recently got a liquid gauge and i'm hitting 22.1 psi peak and getting 258bhp according to the dyno run (i've done the run twice and got the same figures). Does this sound right or is it a possible boost leak in my IC pipes somewhere?

My mods are....

Stage 1 Superchips remap
K04 turbo with upgraded 360 thrust bearings
Forge 007dv
BMC kit
N249 bypass
Longlife exhaust system with 200 cell sports cat
Autobahn 88 TIP

My car doesn't feel as great as it used to at high revs so i'm thinking i have a leak somewhere?


Much appreciated!

Jay
 
i took my bmc of mate and replaced with a jetex.... 12g/s more straight away,, annoying as they are very expensive..... what is your liquid guage saying on airflow?
 
I like my BMC lol. I'm getting 208 g/s so not too bad, obviously i won't get figures likes yours as it's open cone but oh well! What do you get?

So would you happen to know anything about my problem? I was reading your FMIC topic and saw your stutter problem on start up and stopped after you fitted the new hosing. Could i have a split then like you did which is causing my car to stutter on start up also?
 
Could be many things, get a fault scan....first


MAF
Coilpacks misfiring, Spark Plugs
Vacuum leak
Timing belt, Boost Leak
Fuel Pump Relay, CTS
O2 Sensor, Throttle body
 
I would check for vacuum leaks in the first instance, all the pipes under the mani are subject to splitting including the plastic ones which crack...

Only way to say for sure about a boost leak is to get it tested and/or replace all the crappy OEM jubilee clips with hi-torque ones... no need for t-bolt clamps really... Forge sell these clips but you prob can get them cheaper elsewhere but they must be the stainless steel hi-torque ones and not normal ones...

<tuffty/>
 
I've done several scans on my liquid gauge and nothing comes up. I just bought a new MAF a few days ago so i'm all good there. Only thing i can think of really is leaks like Tuffty said. My tech has the boost leak smoke test thingy so will give that a go soon and see how i get it on!

Thanks :)
 
i recon itll be around the manifold as well tbh. gonna be like a smoke screen as a school disco wooo!
 
How can i check under the inlet manifold, bumper off job? No space down there to stick my head in!

Matt bring the led keyrings for strobe effect!
 
remove the plastic trim in front of the mani, unplug the EGT probe wiring plug, undo the 2 allen bolts holding the metal bracket to the inlet mani (5mm allen key), carefully remove the hose clipped to the metal bracket (or have a cable tie ready)

<tuffty/>
 
and that metal tray, lift it out upward as much as possible to raise it from the dip stick tube. if you pull the tube too far to the front itll break
 
I like my BMC lol. I'm getting 208 g/s so not too bad, obviously i won't get figures likes yours as it's open cone but oh well! What do you get?

So would you happen to know anything about my problem? I was reading your FMIC topic and saw your stutter problem on start up and stopped after you fitted the new hosing. Could i have a split then like you did which is causing my car to stutter on start up also?
im getting 226g/s @ 25psi
a pressure test like tufty says is the best way, start of low and work your way up, to around 18-20 psi i used to have one, but can not find mine...another thing to make i think
 
when you do a pressure test, do you hear your engine oil bubbling away? made me wonder if i had a dead seal in the turbot
 
I typically leak test from top hose to top hose and I do a thorough visual check of the stuff under the inlet mani.... S3's normally leak around the intercoolers (where you can't get to the clips) and almost every car I have seen with a FMIC leak at the joiner by the drivers side headlamp (and everywhere else too if they used t-bolt clamps)... the turbo ones are easy enough to get too to check if they are tight...

If that lot can handle 2bar of pressure sustained then all is good... Speedy Steves leaked after 20psi... S3 George's leaked like a sieve on about 10psi!!! crushed pipes using t-bolt clamps being the main culprit...

<tuffty/>
 
when i diy pressure tested mine in forced oil into the turbo and gave me a nice smogscreen for 30seconds when starting it. Mine also had a smoke test which came back with nothing, even though I found split hoses afterward. I put that down to the numptys doing the test
 
Well my friend who owns a TT has quite a few boost leaks now and then due to the amount of boost he's running. He decided to have a quick look in my bay to see if he could find anything. We didn't take the mani off because it was quite late and dark so he had a search with the torch.

He said the PCV pipe under the mani is dirty and quite oily with dust etc stuck to it. He said it's got a leak which could be my problem? He said it should be completely clean looking like his TT one which i saw was mint.

Your thoughts?

Thanks!
 
Plausible.... remove the trim and have a good look... there is an 'L' shaped pipe that comes from the middle(ish) area underneath the mani that goes into the 'air pump' ('Y' shaped plastic thing) and they split underneath...

Any of the rubber pipes under there are prone to splitting...

<tuffty/>