Hi guys,

Firstly, two things! I read the gripe post and as admin elsewhere, I totally get it. I will be grateful for any help given (and tell you so)! 😅

Secondly, I apologise in advance if I posted in wrong place!

So, I bought my daughter a 2006 A4 2.0 tdi cabriolet approximately 18 months ago. It has started daily and ran brilliantly... Until now!

I have a basic knowledge of cars, so bear with me please! 🤣

She told me it had been taking longer to start of late, like a running on three sort of sound which she thought was just cold weather but it still starts first try. Ticks over smoothly, no dipping and absolutely normal once started. This only happened in mornings. She said that today it started to "chug" through gearstick (forward and back) when accelerating but once revs got higher it was fine but she could hear a mild knocking which sounded like exhaust was loose when driving. So gearstick made me think engine mounts or gearbox mounts maybe. Then she said oh it's a bit reeky when it starts but quickly clears!

Anyway, looked under bonnet and egr is disconnected... Spoke to guy who had it before (he bought to sell so knows no more) but he said egr was disconnected when he had it... 18 months ago! 😳 He said he looked at it and it wasn't blocked but if he connected it, limp mode! Well, thanks for telling us at the time! She has done maybe 5k miles in this time and car is low mileage for age at 82k. It's passed emissions twice for mot whilst we have had it.

Then, I remembered running it for codes when we got it and it threw one about inlet manifold flap and one about short to ground too. My female brain totally forgot. I will go and find them (I took pics of it) and then update. 🙈

So I started car and it was chugging whilst cranking pretty bad but did start first try. I noticed fumes coming out engine bay and videod it. Car is quite loud, engine moving more than usually expected on idle I think and a definite ticking sound. Fumes (smells like fumes not smoke) appear to be coming from egr/throttle body area but who knows! Seems the obvious thing but is this likely to be damaged badly elsewhere? Any help appreciated as she adores the car!

Other observations were some oil in between throttle body and egr, throttle body has a screw missing which makes me think someone has looked before and a small oil leak at oil breather pipe. That said, it's not using much oil as she has only ever had to top it up once. No water in oil or vice versa. Thin layer of dried rusty stuff inside coolant lid but coolant is clear and car doesn't overheat. I checked the fuses under steering wheel and they are all OK.

Sorry for long post and thank you in advance for any advice you may give!

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Video is quiet for first second!

Pics of oil I mentioned, neither being a lot

58 minutes ago, Roadrunnerontop said:

Hi guys,

Firstly, two things! I read the gripe post and as admin elsewhere, I totally get it. I will be grateful for any help given (and tell you so)! 😅

Secondly, I apologise in advance if I posted in wrong place!

So, I bought my daughter a 2006 A4 2.0 tdi cabriolet approximately 18 months ago. It has started daily and ran brilliantly... Until now!

I have a basic knowledge of cars, so bear with me please! 🤣

She told me it had been taking longer to start of late, like a running on three sort of sound which she thought was just cold weather but it still starts first try. Ticks over smoothly, no dipping and absolutely normal once started. This only happened in mornings. She said that today it started to "chug" through gearstick (forward and back) when accelerating but once revs got higher it was fine but she could hear a mild knocking which sounded like exhaust was loose when driving. So gearstick made me think engine mounts or gearbox mounts maybe. Then she said oh it's a bit reeky when it starts but quickly clears!

Anyway, looked under bonnet and egr is disconnected... Spoke to guy who had it before (he bought to sell so knows no more) but he said egr was disconnected when he had it... 18 months ago! 😳 He said he looked at it and it wasn't blocked but if he connected it, limp mode! Well, thanks for telling us at the time! She has done maybe 5k miles in this time and car is low mileage for age at 82k. It's passed emissions twice for mot whilst we have had it.

Then, I remembered running it for codes when we got it and it threw one about inlet manifold flap and one about short to ground too. My female brain totally forgot. I will go and find them (I took pics of it) and then update. 🙈

So I started car and it was chugging whilst cranking pretty bad but did start first try. I noticed fumes coming out engine bay and videod it. Car is quite loud, engine moving more than usually expected on idle I think and a definite ticking sound. Fumes (smells like fumes not smoke) appear to be coming from egr/throttle body area but who knows! Seems the obvious thing but is this likely to be damaged badly elsewhere? Any help appreciated as she adores the car!

Other observations were some oil in between throttle body and egr, throttle body has a screw missing which makes me think someone has looked before and a small oil leak at oil breather pipe. That said, it's not using much oil as she has only ever had to top it up once. No water in oil or vice versa. Thin layer of dried rusty stuff inside coolant lid but coolant is clear and car doesn't overheat. I checked the fuses under steering wheel and they are all OK.

Sorry for long post and thank you in advance for any advice you may give!

---

Video is quiet for first second!

Pics of oil I mentioned, neither being a lot

Hi if the manifold flaps are stuck that won't help as that is what causes the air vortex in to the cylinders thus mixing your fuel/air ratios, my guess with the EGR is that no not blocked but stuck shut/open either way that will put you in limp, if you can scan the car again codes are always helpful also check soot/ash loadings in the DPF as blocking can cause excessive back pressure, hence the fumes in the engine bay, I also think your engine mounts may be past their usable life.

Steve.

Thank you Steve for taking the time to reply, I appreciate it!

I found the codes and there was more than I recalled. I will attach. The snap-on one's are the old codes I forgot I'd done.

Last night I ran with obd2 and got p0405 and p0243 only. That was with egr disconnected. I then connected it and ran again, it threw p0652, p405 and p0243. Adding pics for descriptions.

Would the back pressure potentially be responsible for leak at breather pipe? Is it because I forgot I'd run original codes, nothing has been addressed and therefore it's progressed to this point?

Interestingly the engine light isn't on, which baffles me!

Thanks again Steve, worth your weight in gold!

4 hours ago, Roadrunnerontop said:

Thank you Steve for taking the time to reply, I appreciate it!

I found the codes and there was more than I recalled. I will attach. The snap-on one's are the old codes I forgot I'd done.

Last night I ran with obd2 and got p0405 and p0243 only. That was with egr disconnected. I then connected it and ran again, it threw p0652, p405 and p0243. Adding pics for descriptions.

Would the back pressure potentially be responsible for leak at breather pipe? Is it because I forgot I'd run original codes, nothing has been addressed and therefore it's progressed to this point?

Interestingly the engine light isn't on, which baffles me!

Thanks again Steve, worth your weight in gold!

Hi thank you for the codes, basically the EGR is toast, your boost pressure solenoid is on its way out, this is a replaceable item but the underlying issues range from a sticking valve in the turbo body to something as simple as a vacuum leak in the pipe to the solenoid, 0652 is probably the MAF sensor knackered, which I would advise changing the MAP sensor as well as these rely heavily on information correlation, the boost sensor sounds like its alternating between overboost and under boost the overboost will cause the knocking noise, if a new solenoid won't cure it I am afraid the turbo will need replacing.

Steve.

Thank you very much for all your help Steve ☺️