Will removing vacuum lines have an effect on gas mileage?

[STEVEn95tsi]

I just wanted to know.... If i get rid of all my egr, throttle body and intake vacuum hoses...remove all those solenoids...block my egr valve and cap all those vacuum ports...just keeping the vacuum hoses i need... Will that affect the performance of my car?..gas mileage?..engine temp?..etc..THANKS.

--i did a 6 bolt swap and i would like to clean it up a little. But i dont want to pull anything out thats gonna mess around with the way the car performs...

 

[the_mork]

Not really. It will make your engine bay a little bit cleaner but honestly there isn't any difference to power, economy, temp, or really anything else except emissions. Removing your EGR may actually be detrimental to fuel economy but only to a minor degree.

 

[STEVEn95tsi]

Well im getting a fuelab regulator in couple of days... Can i remove the fuel solenoid as well?... Do i unplug all the electrical connectors from the solenoids and take them out or do i leave them in?...And how do you suggest i plug up all the vacuum ports?...

 

[the_mork]

You can get rid of the FPR solenoid with or without getting a new FPR. The solenoid stops vacuum reaching the FPR on a hot start to increase fuel pressure and make the mixture richer.

Unless you have a tuning device (dsmlink, flashable ecu, evo8 ecu) that lets you turn off CELs then you'll need to keep the solenoids plugged into the wiring harness even if you don't keep them vacuum lines. Generally to cap them off all you need to do is get some caps at the auto store and put them on your throttle body.

 

[1990AWD]

not meaning to thread jack...but can you remove all emission stuff while still leaving your EGR on?

 

[STEVEn95tsi]

Great man...thanks a lot

 

[STEVEn95tsi]

Yeah you can leave your egr valve on... it wouldnt be doing anything though.

 

[95fwdtsi18psi]

Make sure you block the egr off with a plate though.

 

[1990AWD]

well I mean a functioning EGR w/o the rest of the emission lines

 

[95fwdtsi18psi]

There are two vac. lines the run off of the valve itself. You will need to cap them off. One runs to the vacuum tree right behind the TB and the other taps into something else, I can't think of it right off hand. You could I guess leave it operational, but why don't you just block it off, or at least plug the vac. ports on it.

 

[Defiant]

Removing the vacuum lines from a DSM is only an engine room appearance mod. You will gain no performance from the operation.