Well all boost leaks should concerns me as long as they rob power. Most boost leaks will not affect idle or normal driving or even WOT acceleration other than loss in performance.

If you have any leaks find it and take care of it. Because your car might run ok with it, but its not at its full potential.

Example, my car is supposed to be around 115 mph trap speed (give or take) with mods below but with my leak its as slow as stock trapping 105 mph. And before the tune with just an exhaust and air filter I was trapping 107.

 

leaks there are actually quite common, along with throttle body shaft seals

 

I had a leak exactly where you have yours. At first my tuner got these thicker O-rings and we used those.. then we found out that my car's timing was off. It was just off enough that the car ran fine, but it wasnt making the power it was supposed to. Try checking your timing and if all the marks, like the ones toward the bottom of the engine.

hope this helps

 

This is a quite common occurance. I've replaced my injector insulators twice since I posted the my thread on this back in Oct 07. https://www.evolutionm.net/forums/ev...ill-stock.html

 

I'm on stock untouched valve train etc... So I dont think my timing would be off and I never mis shifted or did anything that would cause that issue.

As soon as the O-ring comes in (hopefully tomorrow) I'm going to install them and do another leak test. If I am not too happy with the seal (how snug the injectors will be), I will shave the stock fuel rail spacers to make it tighter.

 

For some reason I either havent seen that thread or dont remember it. But thanks for posting.

Where the injectors nice and snug after replacing the o-rings? With mine I can rotate them with a little effort. I was expecting them to be more tightly in place. Also if I try wiggling them with some effort the boost leak would change in tone, as if it seals a little then leaks.

 

They weren't so tight that it was hard to rotate the injectors but when putting the new insulators in the manifold the they didn't just drop in like the old ones but rather had a slight interference fit. If you noticed I also listed the NAPA part number in the other thread. Hope that helps.

 

for reference, this is why its good to do a boost leak test regulalrly.
I did mine like 2 months ago and found a huge one and fixed is in the licp.
Now I did cams and clutch and all that and figured Id might wanna check just in case cuz i took soo much **** off the car
Well i tested and so far I had an enormous leak at the throttle body gasket today. Not the butterfly seals, but the actual gasket. I rtv'd that **** up and gonna test again to see the IM gasket seal and injector seals because of this post.

 

I just did a leak test this afternoon before my track day and #3 was pissing some serious air. Putting very little pressure with my finger on the injector stopped the leak, but then I could hear small ones from the others. Squirted soapy water at the manifold and lots of bubbles from all of them. So from all the heat and wear of racing they've shrank and hardened. Ordered mine should be here Friday hopefully.

I have the same concern about how "loose" the oem rail keeps the oem injectors in place. Hopefully when I go with a diff fuel system that'll get solved. But i'll try the shaving of the spacer in the meantime.

 

Let us know how the shaving goes.

 

hate to bring this back from the dead, but i've run into this problem twice already on the same injector location. First time I noticed it @ 14k miles and now I have 24k again. I also started to smell a faint gas smell in the cabin under WOT...note that I also drive an RS so i'm lacking firewall insulation to smell this!

I think most people are unaware of this problem because we constantly change injectors/seals anyway.

 

bump again...

 

Last time when I changed them, I did a boost leak check and they held fine.

But I'm seriously considering taking off those fuel rail spacers and trimming them slightly. This way the rail can push down the injectors with some more pressure for a better seal. STM sells these spacers, so even if I change my mind I can replace them easily.

 

They are called Viton Seals