[chef423]

Hi everyone, I am upgrading/replacing some of my vacuum lines in my E90. I bought this blue line as I saw another YouTube influencer using them and he said no issues. These blue lines are long life, high heat. Now as I am getting more of the line installed, my car has lost power. I did read that the vacuum lines needed to be 1/4"?

Here is a pic of the new line I am using Vs the stock offering. You can see the black line has more 'space' vs the blue line. Will that matter??

I replaced the lines that go over the engine to the cannisters and now I am seeing the lost power.

Ideas?

[overcoil]

I have no idea..

but the black tubing looks like 1/4 " Inner Diameter and the blue looks like 1/8 " Inner Diameter.

I can imagine the difference in Inner Diameter not creating enough vacuum.

[chef423]

https://www.ecstuning.com/BMW-E90-33..._Purpose/Hose/

Thanks for the input, this link shows the ones I bought and they claim to work for the E90...but you can clearly see the diameter isnt the same...

ESC claims the 4mm line will work...Still confused. I hate trial and error!

[overcoil]

Though it could be possible smaller Inner Diameter creates equal or more vacuum. Like a smaller diameter water pipe creating more exit speed.

So double check all the work you did to see if you accidentally disconnected something - which is common.

[chassis]

chef423 What other work has been done on the vehicle, other than vacuum lines?

[chef423]

I do all my own work....there has been alot done to re-fresh her once I bought her 3 years ago...

BUT, looks like the fix was replacing the 2 boost cannisters and re-flashing my car with the MHD mod. One of the line tabs broke off one of the cannisters when I replaced the line so I had it just laying there until the replacement arrived. I ordered one and PartsGeek sent me a case of 13 LOL! So I replaced them both this morning, all lines hooked up with a fresh flash...BOOM. Car is back to tip-top.

Next upgrade: 7.5" FMIC, the inlets (both VRSF) and the oil pan gasket. Leave it to BMW to make the Oil Pan Gasket the hardest thing to re-fresh but taking half the dang car apart!

[chef423]

Originally Posted by Caravaggio

Though it could be possible smaller Inner Diameter creates equal or more vacuum. Like a smaller diameter water pipe creating more exit speed.

So double check all the work you did to see if you accidentally disconnected something - which is common.

That's great logic...but it seems all is ok now. I guess the blue lines are ok..those lines are NOT cheap!

Thanks for taking the time to post.

[tracer bullet]

Originally Posted by Caravaggio

Though it could be possible smaller Inner Diameter creates equal or more vacuum.

Vacuum is vacuum. But yeah you could restrict flow. Depends how much air it's trying to draw out.

[omasou]

OE always works

[Tambohamilton]

Originally Posted by Caravaggio

Though it could be possible smaller Inner Diameter creates equal or more vacuum. Like a smaller diameter water pipe creating more exit speed.

No, certainly not. In this scenario the smaller diameter could only restrict flow. However it's unlikely to be an issue unless the diameter is really small.