Audi A4 1.8T Rough Idle/Engine Light/Miss-fire/suction/Cure 

Dead set legend!! Saved me a heap of cash at the mechanics telling me there was more problems then just this. Car is running perfect with no errors! Thanks mate!

just to help future people. If you get an EPC light with similar issues its extremely unlikely to be a sludge/valve issue. Look at Crank sensor, maf, sparks, fuel injection.

Hey mate, Good video. Especially the part where the suction was coming from the dipstick/filler. I could not find the source! Never thought that could happen! Cheers!

Had the same problem on my passat and it was the pcv valve. Thanks for the video it helped a lot!!

You sir, are a lifesaver! I had the oil cap suction problem when engine was on + bad idle. I checked the green valve and it was broken. Thank you so much! :)

thank you !!!!! been looking for that parts for months. the closest thing I could find was the breather valve, which have some sort of nipple, or accommodation for a vaccuum line. now I know what to order and can finally fix mine. Living in the Caribbean is awesome, but some when it comes to things like this. again. Thank you.

Top Man Weldone. Very common but the forums would lead you around a world of problems, Nice and simple and easy to understand 👌

Just had negative pressure in vaccum. changed PRV and PCV valve and fixed all the smoke leaks, and double checked the check valves. Fixed the problem. Took my intake manifold off so many times. leave throttle body on if youre taking it off and be prepared to have extra hose clamps unless your factory clamps already done.

I have a 2003 Audi A6 3.0 and was having the same issue it’ sounds as if your engine is done one of those scary expensive feelings but I did a temporary fix with some gorilla tape and worked like a charm!! Lol but thanks for posting this video very helpful!!

thank u so much 👍🏽👍🏽 it cost me $25 and took 25 minutes, now my 1.8t feels normal again

Hello you really helped alot my a4 1.8t was jumping like a mad horse and now is calm as a hamster really bro thanks alot helpfull video 🙏💪👍

Excellent thanks, had this problem and replaced the two items mentioned, worked perfectly

Thanks....Great Help....sorted issue quickly!

PCV was the one for me. I can’t thank you enough mate. Top man 👍🏽👍🏽👍🏽

THANK YOU THANK YOU THANK YOU.........wow.. no one was able to diagnose the problem and this cured my problem instantly. thanks alot.

thanks worked for me...but my pcv was different to yours. mine had a T. anyway i joined the one like your to mine which has the T and everything works smooth!

Have same problem with my b5 Passat .. Tq for this video

Hi James I have a similar issue and am thinking i will change both valves but what was the part No. of the PCV valve.

my car fix no more rough idle I jaz replace the PRV Valve today ...thanks again

Hey mate I'm having the same trouble! I was thinking it was coil or maf but I will add this to the possible list! Ran vag on it and just showing mis fire.

Thanks James I was having the same problems and you are a lifesaver I'm about to order the parts

Had the same problem... Fixed it... I had a broken bleeder valve... Part was cheap... Around 20euro

What's the Parr number for the pcv valve

Are they both good for 2005 audi a4 1.8t?

Am have problems with my 2004 audi a4 quattro 1.8t manual it's idling bad it was idleing bad in the past and find out that one of the vacuum was bad so I changed it an all the other one's the was driving well months later I'm having a bad idle again but not as bad sometime it's harder to start turn off

Hi mate cheers, my pcv valve looks like yours. Did you do an updated video once sorted?

Can anyone help got trouble wiv my aum engine slight black smoke on initial start up and keeps cutting out on idle

Pcv valve and prv valve!! Job done!!!

Mate, you just saved my car from me pouring gasoline on it and blowing it to smithereens. YOU ARE THE MAN!!!!

thanks for this post saved me mucho dinero

and is it fixed ? can you post a video with the car ideling ?

thank you....big help.

My problem was the injectors cups !!!! Two cups had hair crack and loosing boost pressure from injectors . Very common Audi problem . The original injectors cups are made in plastic . I replace mine with billet aluminum anodized and replace injectors filter and o rings .

Does anyone have the link to the video from "David" that James refers to in this video?

good video,, thanks brotha

Hopefully this fixes my problem with my new 03 passat i noticed it started running rough at idle and you could hear something in the engine bay, ive replaced a few rotted vacuum lines when i first got it and that fixed a lot of problems but now it seems as if this is the current problem. Anyway my next paycheck im just replacing the entire vacuum system lol all the lines are dry rotted from living in the desert lol hopefully it ends all my problems

Thank you so much!

Replaced both parts and problem solved, I would say the fault was more the PCV than the crankcase vent valve (PRV) but it was clogged up anyway and worth replacing, Car back to normal.

Hi... You have that problem with cold engine or with hot 2??

Whats the update on your car ?? Because mine is doing the same exact thing, idles rough, but runs fine changed the coil packs and the spark plugs

you should have replaced all the rubber parts at least, I've seen on some videos that they like to fail with age. One more thing to replace would be to replace the metal pipes, I've found some rust in them aswell but since i didn't buy the new ones I've flushed them many times and put them back together. Thinking about replacing them eventually

Hi my car had a rough idle so I bought a pirate pressure release valve it solved the problem for awhile then it started the rough idle again

Thsnk you.👍👍👍

What is the part number for the small green PCV???

This solved my high idle and misfiring on my 190hp bex engine. Thanks a lot 💪😃

Thanks for uploading this video. I changed both of these and its far better. It was pretty clear when I took all the pcv pipework off that it was gunked up.. I've had a very slight issue since and in going to do two things, 1) replace the crank speed sensor (its not been done in its life so no harm). Then start and run a test scan.. Then drop the oil and remove the sump, replace the Pickup pipe so it's clearly flowing.. Then run a test and cross fingers.

I have a 2007 audi a4 2.0 and I've changed ten ignition coils and the spark plugs but when I step on the gas it starts to shake and run rough

part number for the PCV green valve please ?

Last week i have purchased a 2002 Audi 1.8tq 235km, car is running mint except when on idle only it vibrates a lot, could these be the issues?

hi there ... what year is your vehicle ? I have a 2004 Passat 1.8l turbo , does it have the same vacuum routing ?

So what fixed it

Now it’s good?

i have a question im having the same experience i pulled my plugs out and my number 3 cylinder the spark plug was broke the part you gap was gone so i got all new plugs and coil packs and still misfiring running like crap but if i get it up to speed its ok but i had a friend tell me i have a bent valve he said it was from the broken spark plug im still driving the car cause I don't have any transportation but do you think its a bent valve

Just bypass pcv plug up the 2 hoses right after the mass air and vent the pcv too the air so u will not blow oil gaskets works great

Hi James So i have a passat 02year 1.8t and i got the same problem engine vibration and the engine light also I brought it to a mechanik told me it was the timing belt so I changed it and i got the same problem,Any ideas or clue can it be the same problem as yours?, Thanks.

Does your car lag when accelerating?

Part number for pcv valve?

can this cause a check engine light to come on?

Delete the to hoses after the mass air and vent crank hose to the air block off intake crank hoses too then vent the crank hoses aka pvc valve u be fine my audi a4 2004 has 250000 miles i did this to it at 60000 mile so do that

Thank you

ok this is what is happening, i have taken the motor and transmission out of my audi 2003 convrt and put it in a 2003 4 door 1.8 turbo , same year car same motor different style. the problem i am having is the car starts then dies when i let go of the key, it ran perfectly when it was in the other car. i really need to know what is it going to take to rectify this problem ? plz help me with the solution.

hello. I have a 2004 A4 1.8T 6 speed. The car idles rough at each cold start and then stalls. I will have to keep the gas pedal at 800- 1000 rpms to keep the car from stalling. This will happen for about 3-4min at each cold start. Could it be the PCV valve? I was thinking perhaps MAF sensor or the PRV valve. When the engine gets to optimal temperature the vehicle runs smooth.Could you please advise.

have you got part number for the green pcv valve euro parts dont kno wot im on about

Having similar problem but I’m losing antifreeze did this happen to you?

thank you put in new p c v car fixed you saved me loads of euros :)

P.S Where did you get your parts from ?

How did you determine if the diaphragm is cracked on the PRV? Was that crack internal or on housing externally? How would one go about checking the PRVs operation?

Hi. How are you. A question: I have to Audi 2004. A4 Quattro 1.8. Panel light turned on ( check engine. ) Code P0302. The found coolant inside cylinder, so they ll remove head to repair,most likely head gasket. They did, but 8 days later, from the repair, he turned the light on the panel ( check engine ) the same code. What could it be

hy,i have a 1.8t bfb quatrro.i wanted to powertune it to stage 1,but the chip guy said that i have a retard in chanell 20.about 10 degrees witch i understand it is verry dangerous for the engine.i dont have errors,but the car pulled 153 hp instead of 163 factory hp.the guy said the gas explodes in random cilinders before spark.after that,i changed all vvt sistem,gaskets,cold sparkplugs,coils and the distribution sistem.nothing changed.lack of power its still present.i run out of ideeas.the car runs normal,it just shakes a bit at idle,and the fuel consumption its about 20/100 km

HI James I have O4 Audi 1.8T I have same problem if going try this sometime this week very nice video :) what is the pcv valve number? green little one

Do you know the part number for the pcv valve

where is the follow-up video?

Part number for the PCV?

i put the prv valve in and now it whistles really loud HELPPP

MAF? what is that

and when my car is on and i pull the 3 cylinder coil pack out the car runs the same

What year model? I have the exact same symptoms in my 2006 A4 2.0L.

💪💪👌👌👍👍

hi, I have the same car and Im currently getting a lot of fumes in the cabin at all times...any ideas why? Thanks

I found the problem to be a drive axle. I replaced, all control arms in front and the drive axle and my car now drives smooth. I have an Audi A4 2005

Hello, I got a 2005 vw passat 1.8T and shop made me a smoke test for 60$ and they found breather system is cracked on top of oil filter housing. Is that the problem you are explaining right now ?

no

My friend i have changed the coils and spark kit and nothing.... My car has the dip stick broken, steam and oil are leaking... i will replace the broken dip stick.... Thanks!!!! Marcel

secondary air pump

I have sold my problem.;) Thanks!

what year is this?

??

did not solve mmy issue.

just talking while looking at the engine....