yeah thats what i thought they wanted it to leak to make money off of me but you live and you learn

 

Ahh boost leak tests...my favorite. You never know what you can find so it is essential to do this for so many different reasons.

 

worst case scenario being a leaky injector oring and it ignites the fuel from your intake manifold and you set the engine on fire. lol.

or better yet.. your FPR vacuum line disconnects and you no longer have control of fuel pressure.... weeeeeeeee

 

I had this happen to my WRX but no lighting in fire.

 

i hope it atleast has mil.spec seals in it now? not the same oem garbage?

 

I do a boost leak test every time I take off any parts that see boost. Good habit to get into.

 

Good info in here.

For cars that have the Oem or aftermarket boost control solenoid, is capping off the boost source hose or any other hose necessary when testing by connecting a tester to the turbo? I don't cap any lines off but I read one thread that said to plug the boost source line for cars with a manual boost controller

 

When I test my car I just turn in the MBC a few turns. Then turn it back out an equal amount of turns. Its good to make a mark on the top with something like a Paint Marker for this.

But if you've fixed boost leaks then make sure you double check where you're boosts at. You may find yourself holding more boost.

 

At the same time, you don't have to get super ****. If you have one tiny throttle shaft leak at 30psi (when boost is only set to 25psi) that you can barely hear while you have your ear up to it and not even feel, fixing that leak is not going to make one bit of difference.
I replaced seals for a dude not too long ago that was wiggin' out over a tiny leak. He thought his car would have more power after the fix. Nothing. Not a damn bit of difference. Idled, cruised and WOT was the same. Trims didn't change at all. I tried to tell him.

 

exactly
i think people blow this whole boost leak test out of proportion
yes its important to fix the big leaks, or if you have a bunch of small leaks, but you dont need to have every tiny leak fixed to where your not gonna hear any air coming out of the car especially if you have more air pressure then you run boost wise

 

put a pin needle hole in one of your vacuum lines then tell me it doesnt make a difference. do you know what happens when you boost your car to those tiny holes?

 

1psi lost is approx 12-20whp or so.. so boost leaks can kill as much as 100whp given the vehicles setup & the size of leak.

any shaft seal leakage should be fixed no matter what it doesnt effect. i assure you its worse then you think when WOT driving though.

also at the same time, it may not be as bad as when the engines cold the seals are cold, they are stiff.. they leak. so when everythings warmed up his seals may not have been leaking. the shaft seals are alittle different then your typical seal.

 

every leak is a leak...

and to say a throttle body seal leak when the car is sitting there isnt going to "affect much" is WRONG.

any leak affects your tune and power.

The car doesnt have the same thing happening when its being pressure tested as when its running... you arent injecting heated air... and variable up and down pressures at the same time.

Anyone who doesnt pressure test isn't into building something the right way. Plain and simple.

We havent had an evo here in the past 6-8 months without SOME sort of leak. We had an evo X come here from another shop.. There were leaks in his almost new Intercooler..

we replaced the intercooler.. and picked up almost 35whp over before at 1 more psi.

Boost leaks = more boost being required by the turbo to get your engine to ingest your desired boost. More boost = more heat. More heat = more knock. etc...

Cheers

cb

PS we charge 65.00 (our hourly labor rate is 110)... anything beyond that is hourly labor.

I think 65 plus 110 to fix a leak is worth the general 20whp we pick up any day of the week.

 

cbrd has always found leaks on my car and fixed them promptly. It is why i will always go back to them because i know before my car goes on the dyno it will be running properly.

 

the higher the boost prressure, the more important a boost leak test. its best to go through the entire charge system when you pick up a new/used evo or change any i/c pipe/coupler. $65 is a lot cheaper than a new turbo/motor.