annoying boost leaks

[v8GTmac1]

I have been on 4.5psi of boost for 1 year now. the time came to find out why I was unsuccessful at getting any more. 

 

used a leak down tester on 1 turbo

+

BLocked off the other turbo

ended up being the EGR valve, when the boost built up, it pushed open the valve and it made a "Door opening" sound then it all leaked out the sides. 

My fix was a block off plate siliconed shut on both ends. Now after 1 tuning session I got it safely up to 7.5psi and here we go!

[MD355]

@v8GTmac1

Good job !!

By the way, what does the EGR do ? My understanding is that it recirculates warm exhaust gas during startup to warm up the catalysts and reduce pollution... 

So if you have completely removed the catalysts (I have in my car), is there any purpose for the EGR valve to exist ??

[v8GTmac1]

5 hours ago, MD355 said:

@v8GTmac1

Good job !!

By the way, what does the EGR do ? My understanding is that it recirculates warm exhaust gas during startup to warm up the catalysts and reduce pollution... 

So if you have completely removed the catalysts (I have in my car), is there any purpose for the EGR valve to exist ??

Nono it re-routes exhaust gases at higher engine loads back into the intake to burn again.

you are referring to the air injection pump hiding inside the left trunk space. it has the hose coming from the left side and to that valve on the left head. In your case that pump serves no purpose other then to keep the CEL from coming on. 

[MD355]

@v8GTmac1

So the EGR is done to save unburnt gas by burning it again ?

Does it exist in Euro cars as well or is it just for US cars ?

It works at all times ?

What happens if you remove it / disable it ?

[snowrx]

Nothing burns again, EGR is there to dilute the mixture prior to combustion in order to correct emissions.  Removing it should bring up combustion temps and increase NOx levels under certain conditions.

https://en.wikipedia.org/wiki/Exhaust_gas_recirculation

[MD355]

Got it !! Thanks

[v8GTmac1]

Yeah don’t do what I did 😁

but if you have the intake plenum off blow some air into it and check the valve stem for leak 

Edited November 22, 2020 by v8GTmac1

[MD355]

@v8GTmac1

I had it off in June when I installed new ignition coil packs.. I definitely doubt if my mechanic is even willing to check... He hates removing intake manifold..

I don't think my car is leaking boost... If it is leaking, it is probably leaking from the aftermarket BOV..