The Misfire Struggle (1.6 FSI - BAD)

SLEI

New Member
After doing all the plug and coil things I used CRC EGR and carb cleaner and got 3/4 misfire away for a long time last year. Very easy to spray from pipe fitting which comes from cylinder head oil breather. I have used it semi permanently but now missfire is back with rage.

If I unplug EGR connector isn't the check engine light on all the time?
My misfires newer happends with cold engine under 90C and before not even at warm engine with steady cruise or over 3000rpm. This is my first petrol EGR engine and I was thinking that EGR is working like in diesel engines also cold.

Have somebody tried to put 2.0 FSI injectors to BAD? I have tested cleaned set of them but electric connectors are at different place and are shorter is there room for them? Is the spray pattern of FSI injectors symmetric or asymmetric so they have to be in specific position? Bought the 2.0 injectors to a different project but they cost me less than one BAD injector even with new seals and testing. Ultimate goal is drive with E85 so higher flow rate won't hurt.

If the flaps in intake don't move they restrict flow in high revs a lot and cut power.

Where are the plastic support rings as seen in earlier pictures situated? Inside brass caps?

Torque shows AFR of about 13.7 in normal driving do ordinary Bosch WB sensor fit A2? I have unistalled WB meter kit somewhere and going out now getting my hands dirty but have big hands and very old body and don't want to do things many times.
 

nalaver

Member
Good Evening , so misfire only when hot ,below 3000rpm .EGR disconnected makes no difference ? do not worry about MIL we are trying to find fault and EGR wiring is connected to ignition . Have you checked earth supply for coil packs as they would be more prone o misfire at low rpm with low current . The flaps for stratified function wont cause misfire ,the carbon normally causes misfire at low rpm and colder engine but seem as your problem is is with warm ?? is the idle bad ie sounds like running on 3 cylinders when hot ??? Have you added any oil additives ???? by the way EGR works on petrol and diesel engines normally on petrol it works at part throttle when hot kinda like the range you are having issues with .
 

SLEI

New Member
Good Evening , so misfire only when hot ,below 3000rpm .EGR disconnected makes no difference ? do not worry about MIL we are trying to find fault and EGR wiring is connected to ignition . Have you checked earth supply for coil packs as they would be more prone o misfire at low rpm with low current . The flaps for stratified function wont cause misfire ,the carbon normally causes misfire at low rpm and colder engine but seem as your problem is is with warm ?? is the idle bad ie sounds like running on 3 cylinders when hot ??? Have you added any oil additives ???? by the way EGR works on petrol and diesel engines normally on petrol it works at part throttle when hot kinda like the range you are having issues with .
I have hoovered all info about FSI misfire in four different languages since I bought my second A2 and checked all obvious things. As I only get misfire error codes (and didn't get them for long time) I started to check EGR yesterday.
Car starts normally when cold and drives without problems until 90C is at meter and runs ok if I'm driving steady at highway, when I have to stop and accelerate plinking light, missing sparks and missing power. At least last year "driving like you steal it" didn't give errors. Check engine light has even gone off on it own when I haven't bothered to reset it.
I have newer seen any signs of lean burn when I have driven with Torque on tablet, one lambda shows about AFR 13.8 and one is at steady lambda 1. 13.8 shoots to 27 when engine braking and fuel flow is cut.
Rev counter moves a little bit now when idling hot and I stop after driving 40km, misfires allmost every time after that.
I wondered if there could be a tiny crack and water leak somewhere which don't bother at revs but coolant don't disapper and morning starts don't show any signs of this.
My other A2 is TDI and FSI is very rare in Finland so very hard to compare my car to working FSI A2.

I love my A2s as I'm driving on salted roads and dirt road, which is salted at summer to fight dust clouds.

ps. EGR wire is now disconnected, had to take intake pipes and throttle away to get room to work as brake things blocked other side on LHD car. Pipes before throttle were clean and after that quit clean as far as I could see. After assembly and start manifold flap actuator also moved at high revs.

ps2. EGR disconnected no plinking what so ever and low rev power loss is minimal compared how it has been lately but engine very clearly looses some heart beats randomly on rev range.
 
Last edited:

nalaver

Member
I have hoovered all info about FSI misfire in four different languages since I bought my second A2 and checked all obvious things. As I only get misfire error codes (and didn't get them for long time) I started to check EGR yesterday.
Car starts normally when cold and drives without problems until 90C is at meter and runs ok if I'm driving steady at highway, when I have to stop and accelerate plinking light, missing sparks and missing power. At least last year "driving like you steal it" didn't give errors. Check engine light has even gone off on it own when I haven't bothered to reset it.
I have newer seen any signs of lean burn when I have driven with Torque on tablet, one lambda shows about AFR 13.8 and one is at steady lambda 1. 13.8 shoots to 27 when engine braking and fuel flow is cut.
Rev counter moves a little bit now when idling hot and I stop after driving 40km, misfires allmost every time after that.
I wondered if there could be a tiny crack and water leak somewhere which don't bother at revs but coolant don't disapper and morning starts don't show any signs of this.
My other A2 is TDI and FSI is very rare in Finland so very hard to compare my car to working FSI A2.

I love my A2s as I'm driving on salted roads and dirt road, which is salted at summer to fight dust clouds.

ps. EGR wire is now disconnected, had to take intake pipes and throttle away to get room to work as brake things blocked other side on LHD car. Pipes before throttle were clean and after that quit clean as far as I could see. After assembly and start manifold flap actuator also moved at high revs.

ps2. EGR disconnected no plinking what so ever and low rev power loss is minimal compared how it has been lately but engine very clearly looses some heart beats randomly on rev range.
Hi ,so ok eventually , now you need to look at power supply and i would suspect earth cable contact (look for corrosion )this is powering the coil packs . The fault with the EGR valve is most probable the internal resister film (best get a new one ) but drive for a week first to check 1000%
Cheers Alan
 

SLEI

New Member
I cleaned the earth wire on left side of valve cover and checked the earth wire from engine to frame and these didn't do any good last year.
 

katalin21k

New Member
Today after long time i've start to work on the car (free to move since this week). What i did:
- disconnect the egr cable (there 2 cable jacks and if disconnected the car stops right after ignition.
-there are 2 parts one on top of the other that go down to valves i believe.
-the top part got the flap that moves but barely opened since there been a black smoke deposit thin as 2-3 mm (same deposit on the 2nd part)
-the second part got 2 hoses that enter in there : the coolant hose and a second one that i think is for gas (idk)
- i did clean up the hole part , so much deposit in there on both parts.
- the bad part is the deposit goes down to valves (i think) and is so small and curved in there, i've used a toothbrush but is a long way down, cleaned as much as i could.
- the plastic inside the egr meaning the plastic wheels are ok, not broken tooths and now moves ok.
-after all this, car started without problems but same behavior rattle. I only drived 2-3 km, guess i need more to clean the remaining deposits but i doubt the cleaning product did something since ive used hard plastic to cut thru the deposit that got sticked to the body of the parts.
Car works the same meaning after 5 minutes is lose power and 3k+ rpm struggle to move (after 5k rpm it makes a noise a fssss like is losing vacum) and when u try to park it or ur on a stop , just hope to move and not shut down.
No check engine error yet...just run 3km but it will goes on again....
What to do next guys? (another liqui moly valve cleaner, keep it at 3k rpm and push product at 10 sec hoping will clean the down part thru valves? I doubt it since i saw how much deposit is there)
I will do tomorrow a new scan with vcds to check if:
17439 - Intake Manifold Tuning Valve (N316)
P1031 - 35-00 - Setpoint Not Reached ( it should be fixed since the flap moves freely now)
vacuum pump.jpg At 1 is the electronic senzor and at 2 is the actuator?need to check if the actuator rod is not broken.

Update today:
It toked me some time to get access to the actuator rod (cheap plastic) that is down by default cus of the rubber membrane from top and when it needed it pulls up using vacuum to suck. Since is broken and not require so much force to pull the leader up i used superglue and went ok for 2-3 km :) I will buy a new one because it sure not much max 20-25 euros but the problem is other is hidden near distribution, i needed to open the plastic cover and the bottom bolt of actuator is hidden there (need to know when new part comes for replacement).

Also scan from today, covering all work on egr cleaning and this valve, after clearing codes surprise no faults but car runs like s**t.
 

Attachments

Last edited:

Andrew

A2OC Donor
.....
I will do tomorrow a new scan with vcds to check if:
17439 - Intake Manifold Tuning Valve (N316)
P1031 - 35-00 - Setpoint Not Reached ( it should be fixed since the flap moves freely now)
View attachment 65369 At 1 is the electronic senzor and at 2 is the actuator?need to check if the actuator rod is not broken.
Can you confirm you have an engine code BAD.

In a BAD FSI, ...

If by electronic sensor you mean the flap potentiometer then item 1 in your picture is not it.
Item 2 is the vacuum actuator for the flaps with the arm extending below it at an angle. The flap potentiometer is next to the bottom of the arm out of sight.

If you want further assistance I can post some pictures.

I doubt a flap problem is the reason for the poor running you describe.

Sorry to be brief but it is late.

Andy
 

nalaver

Member
Today after long time i've start to work on the car (free to move since this week). What i did:
- disconnect the egr cable (there 2 cable jacks and if disconnected the car stops right after ignition.
-there are 2 parts one on top of the other that go down to valves i believe.
-the top part got the flap that moves but barely opened since there been a black smoke deposit thin as 2-3 mm (same deposit on the 2nd part)
-the second part got 2 hoses that enter in there : the coolant hose and a second one that i think is for gas (idk)
- i did clean up the hole part , so much deposit in there on both parts.
- the bad part is the deposit goes down to valves (i think) and is so small and curved in there, i've used a toothbrush but is a long way down, cleaned as much as i could.
- the plastic inside the egr meaning the plastic wheels are ok, not broken tooths and now moves ok.
-after all this, car started without problems but same behavior rattle. I only drived 2-3 km, guess i need more to clean the remaining deposits but i doubt the cleaning product did something since ive used hard plastic to cut thru the deposit that got sticked to the body of the parts.
Car works the same meaning after 5 minutes is lose power and 3k+ rpm struggle to move (after 5k rpm it makes a noise a fssss like is losing vacum) and when u try to park it or ur on a stop , just hope to move and not shut down.
No check engine error yet...just run 3km but it will goes on again....
What to do next guys? (another liqui moly valve cleaner, keep it at 3k rpm and push product at 10 sec hoping will clean the down part thru valves? I doubt it since i saw how much deposit is there)
I will do tomorrow a new scan with vcds to check if:
17439 - Intake Manifold Tuning Valve (N316)
P1031 - 35-00 - Setpoint Not Reached ( it should be fixed since the flap moves freely now)
View attachment 65369 At 1 is the electronic senzor and at 2 is the actuator?need to check if the actuator rod is not broken.

Update today:
It toked me some time to get access to the actuator rod (cheap plastic) that is down by default cus of the rubber membrane from top and when it needed it pulls up using vacuum to suck. Since is broken and not require so much force to pull the leader up i used superglue and went ok for 2-3 km :) I will buy a new one because it sure not much max 20-25 euros but the problem is other is hidden near distribution, i needed to open the plastic cover and the bottom bolt of actuator is hidden there (need to know when new part comes for replacement).

Also scan from today, covering all work on egr cleaning and this valve, after clearing codes surprise no faults but car runs like s**t.
Hi silly me do you just loose power or is there a misfire with hissing noise ? ,so this car has a cat fitted these can easily block after high km, so create an air leak upstream of the cat easiest is to remove the lambda sensor or loosen exhaust , this is going to make some noise but a quick sprint shall show if performance has increased , back to carbon deposits to clean you need small camera and thin pipe connected to vacuum ,the pipe should act as tool and means of removing dirty cleaning solvent , do make sure valves are closed ,so one cylinder at a time , with this job take your time and protect your back ....The plastic that causes problems in EGR valve is in electrical voltage resistor 0 to 5 volt is what the output should read.
the motor is normally ok some do develop gear problems but rare. So to recap the hissing at high rpm is caused normally by blocked exhaust ,the poor low end is caused by carbon deposits the plastic arm from vacuum cylinder does have a sensor that tells ecu position of flap ,this is easily tested ,however the flap is most probably not going to affect performance too much !! Cheers Al
 

katalin21k

New Member
@nalaver
My mistake there are 2 plugs, the top one from egr is positioned back hard to access and it only send power to the flap (the one you told me to disconnect) , the 2nd one is the 2nd layer where the fuel rail and coolant come and if disconnected ofc if is no fuel car shuts down (electronic acceleration), down from there goes to valves and is getting hard to get there and clean (30 cm+ more than i could get my hand pushed).
The noise i think is coming from that vacuum pump since the small plastic is broken to activate the flap it needs to move up and is doing that sucking air, applying more and more pressure to move it up till max but since is not moving i hear the noise( i think).
actuator rod.jpg
Normally in car is stay like this but upside down, moving the top metal. How stupid vag been to use plastic to move a metalic flap, ofc it will break and new one is 120 euros.
I've checked the Egr inside circuit 4 connectors and the plastic gears, they were ok (good hard plastic there).
Now i think i will remove my exhaust just down below 1st lambda or how is called the temperature probe, it will make noise but for test see any changes.
 

Attachments

Varg327

New Member
Hi guys! First post.. ive been looking into all of your problems as had the same thing with my newly bought a2 1.6fsi.

did all sort of repairs, coils, vacuum actuator, teared down intake and cleaned. Nothing different with idle issue..

then, finaly!

opened up the breather box on the rear of the engine. Cracked membrane and alot of junk..cleaned and made a temporary fix on the membrane with gasket on tube..

Put i back in.. every issue disapered after this. Hope this helps..
 

Edwrai

Member
@Varg327
Do you mean the PCV CrankCase Breather (Pipe/Hose?) The rattle problems come from ignition problems because of carbon deposits on injectors, i doubt this pipe can help car run smooth at idle. Plus temporary fix, you think we are kids? that's a pressure hose u cant put band aid and hope car fly to the sky.
Why there have to be trolls when we all try to fix our cars.
Put a video with car running with broken hose and buy new one i found its like 30 euros and show us how smooth runs after, or make picture to see exactly what hose you mean. Is it looks like this one? the oil can?
The crankcase breather can cause issues I’ve seen this with oil usage on the MPI engine.


Sent from my iPhone using Tapatalk
 

Varg327

New Member
@Varg327
Do you mean the PCV CrankCase Breather (Pipe/Hose?) The rattle problems come from ignition problems because of carbon deposits on injectors, i doubt this pipe can help car run smooth at idle. Plus temporary fix, you think we are kids? that's a pressure hose u cant put band aid and hope car fly to the sky.
Why there have to be trolls when we all try to fix our cars.
Put a video with car running with broken hose and buy new one i found its like 30 euros and show us how smooth runs after, or make picture to see exactly what hose you mean. Is it looks like this one? the oil can?
Well! If you realy read my post. It says that i did a temporary fix on the membrane too see what happend. And the problems left with that fix. After this i ordered a new breatherbox. And mine is now fine.. i wanted too let you guys know what fixed mine and what i did, if you have a problem with that, please let me know...
 

katalin21k

New Member
Did you mean pcv valve?

Also if this one is the right piece then i'm afraid you are right. The oil goes right to intake manifold and that's why it build carbon deposits. It has to be checked regularly to not get full, but who does that? Is like your car got own pee bag and u need to check it if u don't want to smell.
 
Last edited:

katalin21k

New Member
For the UK guys there is a hope. Here look how fast a pro shop fixed a car when they have the tools ( missfire and eml on dash). Is a different car but same problems from a vw typical car even is a past generation.


It seems all got problems with missfire and is related to carbon build and bad injectors with dirty cheap orings , pcv valve and cheap thermostat. I've been amazed how fast they cleaned the valves.
 

SLEI

New Member
Very easy to do fast injector work and clean manifold when You have 2 feet more room and intake manifold is at front of engine and not between engine and firewall.
 
Top