Where's the exhaust leak?

[#1HotRod]

I instantly first thought of engine damage, then felt hopefully only a gasket. Started with that dreaded tap, tap, tap, rapidly becoming quicker & louder, pulled over & then realized (God, I hope so) is a gasket. Limped the few blocks home, seemingly loosing power along the way & made it up my steep driveway. Is on pass. side, now very loud but with hand feeling about can't feel any leaking air nor see any discolored blow-by...real hard to tell where coming from. It's not at the downpipe to exhaust flange & don't think from downpipe to turbo housing. Guess can be header to head but I understand there's generally no gasket there, so perhaps is that doughnut between header and crossover? Perhaps cracked header, but don't see any crack.
Is there a diagnostic way to best-guess where the leak is? Don't want to tear all apart & perhaps still not be able to tell (because not many gaskets to begin with) where leak is from. It may help to know it is very loud now and car lost power.
Thanks, experienced input really appreciated.

 

[Pronto]

Youtube diy smoke machine.

 

[bpman1234]

If you have a wet dry vac put the hose in the tail pipe then get some dish washing liquid with some water in a spray bottle and spray around all welds and where ever you think there is a leak .the bubbles will tell you .dont forget to stuff a rag on the other tail pipe.

 

[Night_train01]

My guess is a small crack in the exhaust manifold, likely from a weld

 

[bpman1234]

Between the 3 and 5 tubes .

 

[Jerryl]

I may be over thinking this . . Pressurizing the exhaust works no doubt.

Always wondered if any lodged debri in the exhaust system would get into the cylinder. With my luck it probably would. Lol

 

[Pronto]

Smoke pots use very low pressure, like 1-2 psi...

 

[No disintegrations]

I may be over thinking this . . Pressurizing the exhaust works no doubt.

Always wondered if any lodged debri in the exhaust system would get into the cylinder. With my luck it probably would. Lol

For the shop vac idea; if nervous about debris. One could make a tee fitting to bleed off some of the shop vac volume so just a slight pressure if made in the headers.

Normally you'll see carbon or soot at the leak if it's been running that way.

 

[earlbrown]

The shop vac idea won't have any flow to send debris around (and certainly not more flow than when the engine is running). Moral of the story, if the engine can't spit it out, a shop vac damn sure can't stuff it into a cylinder.

My money is on head gasket from what I've read so far. Exhaust leaks only cost power if they're preturbo AND lower the boost.

 

[ek02]

Three feet of 5/8" heater hose used to listen around the headers and exhaust system will pin point a leak easily. Been doing it for many years. It works better than any other method for finding a cracked header.

 

[earlbrown]

.....and if you hit a blown head gasket you're ear drum will make sure you know!

 

[wilkinsde]

Mine was simple as a couple of loose header/manifold bolts on the passenger side. The back one is a little difficult to reach.

 

[earlbrown]

Mine was simple as a couple of loose header/manifold bolts on the passenger side. The back one is a little difficult to reach.

If you're not running one of my header bolt kits, the trick there is to cut off the stupid nipples on the bolts that don't need them. I.E. the entire passenger side.

 

[#1HotRod]

Thanks guys, you make it seem simple (but we know it's difficult to see &/or feel around that area. Don't know why didn't already do the rubber tubing trick...done that few times with my V8 hot rod. Pronto's idea of a smudge pot is good idea if can figure way get smoke blowing through, perhaps have a buddy use his bong

 

[earlbrown]

If you're never welded up the DS header, it's cracked.

That crack isn't really a 'common problem', it's more like ALL cars do it.

 

[belsie]

On this note: what is the popular & accepted way to seal the pass. side header to the Turbo? "Gasket or not" and how critical is this area? 2 gaskets in case of poor seal? This seems like a weak link? Thanks in advance for your advice & suggestions !

 

[bpman1234]

I used the rjc gasket its reusable.

 

[Chuck Leeper]

Filed flat on both surfaces, light coat of hi temp silicone....Been doing it this way for 30 yrs...NP.
Self locking nuts. lock washers WILL lose tension from the 1300* heat.

 

[belsie]

Thank you gentlemen...........................