hello 2003 audi a4 1.8t had all my vacuum lines canceled so i seen a vacuum line that comes from manifold pluged and the line from the diverter valve also cut so.i did some search and they said to ru


Asked by May 02, 2015 at 02:14 PM about the 2003 Audi A4 1.8T Sedan FWD

Question type: Maintenance & Repair

hello 2003 audi a4 1.8t had all my
vacuum lines canceled so i seen a
vacuum line that comes from
manifold pluged and the line from the
diverter valve also cut so.i did some
search and they said to run a new one
and i did it turned on but when i turn
engine off and tried to start again it
didnt want to until like the 3 time this
happened everytime so i put pag the
old line that had a plug and left other
hanging like before and i started it
and it still does the same doesnt start
till like the third time i try idk what to
do know does anyone know what
went wrong or why this happens?is
there extra air in manifold?

12 Answers

I don't know what you mean by all vacuum lines 'cancelled' But there should be no hoses hanging without a 'home' and extra air in manifold..no. At idle there is a lot of vacuum in intake manifold and drops with throttle.

1 people found this helpful.

It just occurred to me that 'extra air' is vacuum leak...click for full screen

3 people found this helpful.

i.had really.bad vacuum leaks about.a month ago so this mecanic plugged.the.air.lines.wich you can do.i.have.seen many.audis with put.them the only.bad thing.is.he.took the diverter valve and cut.the little hose and it was working Fine until i tried to.reconect it to.the top manifold port the little one thats on the corner thats When the car started but once i.turn ut off to.start it agaim thats when it just sounds like it wants to.start but it wont until.like the 3 try so i put.everything back.to.how.it was.before but its still not.turning on right away so now im confused when it does.turn on it doesnt idle rough or.anything it seems normal its just the starting.part

1 people found this helpful.

forgot to.mention that before i tried to hook this line up everything was good no rough idle

1 people found this helpful.

I believe you, don't get me wrong. But that's a new one on me, being able to plug all vacuum lines. You have no EVAP, no PCV, and that may be part of the trouble. Without a vacuum line your EVAP canister will not purge and that can cause problems starting.

Keep in mind everything is going to have to be put back to factory specs if you live anywhere you have to have emissions testing. It will never pass

Best Answer Mark helpful

yea thanks bud i live in mexico.haha so.they dont care here.but do you think it can be the fuel.injecters or starter?cus if.its back to.how.i.had it i dont see why the problem doesnt stop if it was running fine idk but thank you

No, not starter, it cranks over. Not injectors either because it ran fine before

But you really need PCV. that sucks the blowby out of the crankcase and will greatly shorten oil life


ok.thanks hopefully will.find a good audi.mecanic here.its kinda hard thanks for.you.help


I just had found out the reason my Audi rpm gauge was jumping was because of one of the vacuum hoses was worn out and stripped.. it made the hissing noise.. as a matter of fact I am now thinking I should switch all of the hoses.... my Audi wont even start when sitting cold for at least 8 hours. it will have a hard time to do so...

1 people found this helpful.

Yeah and that pcv either replace it or for under ten bucks get a new one.

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