Boost leak test with TMIC

[gazzy2000]

Hey,

I have googled how to carry out boost leak tests and the interweb seems to only cater for fella's with FMIC's.

I just need to know the ins and outs for doing it on a V5 with a TM.

Can ya help?

Cheers

gazza

[log1call]

Check all your pipeing and tighten all the clamps?

Use a gas while the motor is idling to see if there are any leaks into the system.

Some people use an inflamable gas and watch for reving up, others use an inert gas and look for faltering. The second option is probably safer.

Ether in a can or brake cleaning fluid are both popular.

[pl0x]

 gazzy2000 said:

Hey,

I have googled how to carry out boost leak tests and the interweb seems to only cater for fella's with FMIC's.

I just need to know the ins and outs for doing it on a V5 with a TM.

Can ya help?

Cheers

gazza

I haven't been up to date with your car etc but have you got low boost and smell of fuel/running rich?

i think i may have the same prob - afm reading x air flow then injecting that much fuel, but losing some that air then running rich?

[gazzy2000]

 log1call said:

Check all your pipeing and tighten all the clamps?

Use a gas while the motor is idling to see if there are any leaks into the system.

Some people use an inflamable gas and watch for reving up, others use an inert gas and look for faltering. The second option is probably safer.

cool thanks, but thats just for vacume leaks aye?

I am talking about making the home made valve adaptor and pumping 10-20 PSI to see if it holds it, using soaping water etc to find leaks, this is how they do it yea?

Similar to here (but this is for a FMIC) http://forums.nasioc.com/forums/showthread.php?t=879900

Thanks

[gazzy2000]

 pl0x']

[quote name='gazzy2000 said:

Hey,

I have googled how to carry out boost leak tests and the interweb seems to only cater for fella's with FMIC's.

I just need to know the ins and outs for doing it on a V5 with a TM.

Can ya help?

Cheers

gazza

/quote]

I haven't been up to date with your car etc but have you got low boost and smell of fuel/running rich?

i think i may have the same prob - afm reading x air flow then injecting that much fuel, but losing some that air then running rich?

Yea i have low boost and definately running rich as per Air fuel analyser road test. Cant smell fuel though

[log1call]

Yeah the gas will find vacumm leaks but might not find leaks under pressure, although, often a big leak under pressure will be a small leak under vacumm.

[Guest keltik]

My rangi method:

Plug an air compressor onto one of your manifold vac fittings, pressurise it all up to 15psi and listen for air leaks or attack everything with soapy water. Make sure to prop the throttle wide open too

[pl0x]

 keltik said:

My rangi method:

Plug an air compressor onto one of your manifold vac fittings, pressurise it all up to 15psi and listen for air leaks or attack everything with soapy water. Make sure to prop the throttle wide open too

must have to block off somewere?

[gazzy2000]

Here is another link relating to the boost leak test, http://www.iwsti.com/forums/how-install/119676-diy-another-boost-leak-tester.html

But what i am failing to understand (as were ppl in that thread) is if you place your DIY boost leak adaptor at the inlet bend like in the following pic,

- what do you have to cap off so you dont get false boost leak readings i.e. PCV hoses?

- and surely the test wont work if the throttle butterfly is open (becasue valves open in engine etc) and if its shut i bet its not a tight seal!

- and what if the boost leak is actually somewhere in the manifold anyways??

has anyone actually done this test or one like it??

[log1call]

Try the gas test first... it's easier and might find your leak.

[pl0x]

explain it please? spray brake cleaner round the engine while idling? when the idle change after spraying in a certain spot doing it again till you find where its leaking from?

[Guest keltik]

Lol i hope you dont like your paint. Brake cleaner eats through that stuff nicely. That test only works on vac lines anyways.

Your not pumping it up and seeing if it will hold pressure, your just pressurising the system so you can look for the leak.

[gazzy2000]

is carb cleaner better?

[pl0x]

yea i was thinking wdf lol?

[gazzy2000]

what about that spray and walk away stuff? that looks good too! LOL

[log1call]

Yeah, brake cleaner takes paint off? I don't know because I have never got it on paint.

Try what these guys say then. What ever you use, figure out if it's going to speed the car up or slow it down when it burns by squirting a bit in a vacumm hose somewhere.

Then have the car idling and squirt a bit around anywhere you think there could be an air leak. If the leak is reasonable big, like a gasket say, it will show up. If it's something like a loose hose-clamp allowing the hose to expand under pressure then it may not reveal the leak. I did say to check all the clamps first though.

(Edit) Actually I have had it on backing plates and I don't think it took the paint off now that I think about it. I'm not certain because I hardly ever use the stuff, but I don't remember seeing it strip paint. Any other opinions?

[pl0x]

could use CRC? or some filter air cleaner type spray? would some degreaser spray work?

should really check things like intercooler gaskets, intercooler pipes etc main easy stuff before spraying things round your engine bay lol?

[gazzy2000]

i believe engine start or carb cleaner is the shizz

[pl0x]

mhm i could pour petrol all over my engine and drop a match, at idle anywhere which isn't on fire is vacuum?

but really yea something thats not going to eat away at vac lines etc haha

[log1call]

In the olden days we used to use lpg, but that's a bit of an explosion risk.

I'll leave it to all you smart young fellahs to figure out what to use and how to to use it.

[gazzy2000]

 pl0x said:

mhm i could pour petrol all over my engine and drop a match, at idle anywhere which isn't on fire is vacuum?

but really yea something thats not going to eat away at vac lines etc haha

now your talking LMAO

OR how about making a make-shift snorkle on the air box then drive it into a river up to the windscreen, leave it idling while you swim around it with a mask and snorkle looking for bubbles.

If it stalls well you probably have a vac leak

[Guest keltik]

If your trying to find a vac leak all of this sounds reasonable. But if your trying to find a boost leak its largely useless as the intake tract isnt under any vacuum at idle. Hell 90% of the air is going through the IAC valve which bypasses the intercooler

Maybe im missing something but all of this just seems obvious

[log1call]

Nah you are right there Keltik.

I kind of assume that people that are working on their own cars will figure stuff out.

The gas will get sucked into the manifold and is a good test for gaskets. Further back you need to use other methods, like block off the inlet a little so you have a vacumm right from the air cleaner.

Other than that... make the adaptor and pressurise it, at least then you are really sure the leak under pressure will show up.

[gazzy2000]

yip, i am not interested in vac leaks, its boost leaks i am looking for.

I got brand new vac hoses alround.

Hence the subject/title of this this thread that i started!

[log1call]

Well you will have to make an adaptor and pressurise the inlet. Hoses could be pumped out under pressure and leak.

Have you had a look for signs of leakage, like a bit of a damp patch around joins say?

Are you really sure it is lost boost? Perhaps the motor isn't going right and so not boosting?