Cleaned out my EGR at the weekend and...

[RS84]

...still getting a ****** insufficient air-flow error up.

Took out the valve and used a whole can of carb and intake cleaner cleaning it out until there was no crud left at all.

Dropped it back in, tightened it all up and cleared the fault code. Took it for a spin and all seemed fine... couple of starts later and the emissions control system light is back on the dash grrr.

Anyone else any experience of this?

Are there any other components that could be bringing this error up?

 

[Johnny Bravo]

What error message do you get exactly?
I had to change the EGR too because the vacuum part was broken. Now, after ~4 months, the intake flap gave up. This one is 3 times more expensive than the EGR

 

[c_w]

Is the EGR the bit on the front of the engine where the boost pipe connects?

 

[Lewis583]

The insufficient flow points to the valve not actually opening when requested by the ECU. Either the actuator rod is siezed or the diaphragm/vac pipe to the diaphragm is leaking.

 

[RS84]

I don't have the code to hand here, I'll post up the ross-tech wiki link when I get home from work...

That intake flap is notorious! I checked to make sure mine was opening and closing OK while I had the EGR off because I've read so many threads on the motor failing in it.

Plenty of info on it here,

http://www.audi-sport.net/vb/new-a3...manifold-flap-egr-valve-how-do-i-solve-2.html

I think the motorsport version of the Allard EGR delete kit also removes the flap unit... Prob be a whole lot cheaper than a new one from Audi!

 

[RS84]

Is the EGR the bit on the front of the engine where the boost pipe connects?

The one fixed to the intake manifold with the silver exhaust feed coming into it from the right. The unit mated directly below it contains the intake flap.

 

[RS84]

The insufficient flow points to the valve not actually opening when requested by the ECU. Either the actuator rod is siezed or the diaphragm/vac pipe to the diaphragm is leaking.

Can I test this manually? Get the hoover at it or something...

Should I expect to see much movement from the rod?

(That's it before the clean!)

 

[navnayyar]

I had this, couldnt be bothered in the end fixing it ad replacing it with a egr delete kit and mapping it out fixed it

 

[RS84]

I had this, couldnt be bothered in the end fixing it ad replacing it with a egr delete kit and mapping it out fixed it

Been looking into deleting the ****** thing too.

Did you get the EGR cylces mapped out or did they just prevent the ECU from logging that fault code?

 

[navnayyar]

Been looking into deleting the ****** thing too.

Did you get the EGR cylces mapped out or did they just prevent the ECU from logging that fault code?

Both, light and cycle

 

[RS84]

What error message do you get exactly?

16785/P0401/001025 - Ross-Tech Wiki

 

[ryanstewart9]

Anyone know how much mapping companies normally charge to just map out the light & cycle?

 

[paddy]

Out of interest..if you clear a fault code it will not come back until it faults a further 3 times which is why you initially cleared it and then it came back after e few starts.

 

[NHN]

Have you actually checked the flap itself inside to see if no teeth are broken instead of the egr.

 

[navnayyar]

Anyone know how much mapping companies normally charge to just map out the light & cycle?

I got mine free because i already have one of their maps otherwise it would have been £100 i think. Check link FR&R Tuning| ECU Remapping| Stage 1, 2 & 3 Performance Upgrades - VAG 2.0 TDI EGR Roadsport Delete kit - (Powered by CubeCart)

 

[RS84]

Out of interest..if you clear a fault code it will not come back until it faults a further 3 times which is why you initially cleared it and then it came back after e few starts.

Useful to know, thanks.

Have you actually checked the flap itself inside to see if no teeth are broken instead of the egr.

The flap on mine seems to be working fine, just the EGR I'm having trouble with. As was said below it's either the rod has seized or the diaphragm ist kaput... I'll have to take it out again for a look a couple of those bolts at the back are a nightmare to get at!

If the motor in the flap has failed it throws its own seperate fault code. It's somewhere in the thread link I posted earlier.

 

[NHN]

I didnt say it failed, I said the teeth may of broken & it functions sometimes ok, this has happened to others BTW, thus fault code thrown about insufficient air, worth a look anyway to be sure as these have been very unreliable, you may have the updated one already, something to discount.

 

[RS84]

I didnt say it failed, I said the teeth may of broken & it functions sometimes ok, this has happened to others BTW, thus fault code thrown about insufficient air, worth a look anyway to be sure as these have been very unreliable, you may have the updated one already, something to discount.

Ah sorry, I see. Yeah certainly can't harm to have a look. Is it easy to take the cover off the motor without damaging it?

Any idea where the sensor that logs the fault in question is?

 

[NHN]

Yeah fairly easy to remove, its only a pressured plate, just lever edges up, have a looksy inside, then push back on & tap the corners back over with a hammer gently, job done.

There's a sensor on the IC piping just behind the rad, maybe its this.

 

[RS84]

Actually thinking about it now, when I took the EGR out the IMF was open... surely it should have been closed if the engine wasn't running?

 

[RS84]

Anyone?

 

[NHN]

Ok have you actually checked the egr flap/actuator at rear of engine as this maybe is getting stuck.

 

[RS84]

Ok have you actually checked the egr flap/actuator at rear of engine as this maybe is getting stuck.

I checked the flap in the IMF when I had the EGR out, but I only pushed it down a couple of times. The flap was open, and returned to the open position each time. No real resistance on it. I suppose if there are only a couple of teeth broken on the cog it would only fail 1 or 2 times per rotation.

Should the flap be in the closed position when the engine is off?

 

[NHN]

Please read my post again mate.

 

[RS84]

Please read my post again mate.

Sorry NHN I must be misunderstanding you!

When you say egr flap/actuator do you mean the rod in the EGR or the flap in the IMF?

Apologies for the ignorance and thank you for the help so far!

 

[NHN]

The egr unit itself is at the front, my post advised to check the egr flap/actuator thats at the rear of the engine, there's an egr cooler iirc on bkd's anyway that supplies the egr at the front through that inch or so thick pipe to the right. in one of the pics above, maybe this is getting stuck.

 

[RS84]

The egr unit itself is at the front, my post advised to check the egr flap/actuator thats at the rear of the engine, there's an egr cooler iirc on bkd's anyway that supplies the egr at the front through that inch or so thick pipe to the right. in one of the pics above, maybe this is getting stuck.

Ah I follow, cheers mate!

I just assumed that pipe was a straight feed from the exhaust manifold without any valves etc.

Didn't know the recirculated gases were cooled either!

 

[a3glenn]

for sure it is a EGR valve broke, same fault on mine, if you suck on the vac pipe there will be no resistance (air leak) same withe the error codes, cleared them the came back a day later

change your egr