Printable View
hi bought a 2005 a4 2.0 tdi 140 every now and then goes into limp mode switch off engine restart everything fine took egr valve off today cleaned it , it was not that bad really maf looks new, car a had turbo about a year ago guessing who ever did it cleaned egr then, while in limp mode today got a code checked it was turbo underboost po 299 no engine light on dash and when car was restarted no fault code so trying to find what to check next can anyone help me thanks :1zhelp:
Check all visible pipes/hoses and have a look here
16683/P0299/000665 - Ross-Tech Wiki
Sent from my iPhone using Tapatalk
I had that exact same fault, and it was a cheap fix. It was the vacuum actuator on the inlet manifold. Inside there is a diaphram which splits. you have to replace the whole unit. Only about £10 + another £10 for new gasgets. You will also need a couple of cans of choke cleaner to clean the inlet manifold out while it's off. It's quite an easy job. The unit is used to operate the flaps inside the inlet manifold and when split does not function properly. however mine is a 2007 so it may not be the same on yours.
Car runs great afterwards
Here is a pic of the part, it is at the top of the engine near the front. Part number is S03G129061C
Attachment 21399
thanks will check all
Hi all, just move over from the A2 forum, have an Audi A3 2.0 TDI. 09 plate. It’s another P0299 code fault - Turbo issue. I had this happen with the glow plug warning light coming on for a couple of weeks and then the engine management light come on with it last week. Usual loss of power. But after switching off the ignitions= it reset its self ( Glow Plug only) I cleared the fault code. And set about problem solving it. I change the oil,filter, fuel and air filters. “Been naughty and failed to do it last year so its gone nearly two years with 24k on the clock- I know, not good. So, having done that I tried the car over a few days and it had little effect on the P0299 fault. I then inspected the car and noticed the N75 sensor wasn’t on its mounting, just hanging down. Now the top Grey cap is sitting up right on its holding clip.( this wasn’t taken off when removing the oil filter but I had it serviced at a garage the year before- well near of 2 years and they left it hanging down.
Now, one day has passed and there is improvement – it failed go into fault over 50mph which it did previously. I then added some Forte Diesel Cleaner yesterday and since then I got the car up to 70mph with out a failure, but above that I had one glow plog warning come on. I stop the car turned off/ on and cleared the fault and drove on again reaching 80mph for about 10 miles and it came on again, I again stop and switch off/on and continued driving home and after 20 miles I ran it at 80mph and for the last 20 miles no return glow plug warning and loss of power.
Question: is it critical to have the N75 sensor vertical? Could this be the root cause?
Or has the magic Forte turbo cleaner worked?
Or possible a combination of all 3 with the filter changes?
(Ps also ensured all pipe work no leaks which there wasn’t)
Your views.
hi all just a update i checked all pipework etc all seemed good , i then checked air filter it was a bit black lol so drove with no air filter in when i went to buy a new one wow car was great lots of power and no limp mode , i put new filter in on sunday and its been fine since so maybe its ok now but will keep you all posted but for now im happy , im sure it cant be just down to a mucky air filter but hey its working so far .
well its done it again after 2 weeks thought i had fixed it but no im sick of it so heres my problem im looking for the vacuum actuator on the inlet manifold. as one guy said it could be that but i cant find one on this car i have 2 on the other side of engine above turbo but none anywhere near the egr unit
Just to add to my fault: I've change N75 solenoid and the Vacuum little pump and the MAS - still have the same issue. Did notice a leak on the exhaust manifold, soot and I took the clamp off but unable to force apart to look into the Turbo side but there is oily soot on the clamp*. I tighten it up and tested but still my fault is there. I can make it fault by driving in 6th gear at 70mph and at 2100 revs if I accelerate hard it then its a flat point and the glow plug warning comes on. If I stay in 5th gear and do the same its ok. So keeping it in a low gear is fine but to higher gear and over acceleration and it cant cope. I've pulled a vacuum on actuator and had some movement on it, but not sure if its fully functional. * I'm thinking the turbo is fouled up with oily slug. Was thinking of flushing it with tubo cleaner but ive got to the point now where I'm gona take the bullet and remove the turbo for cleaning but whilst i'm capable of that my heart isn't in wasting a day doing so getting black and bruised so may its of to the dealer and have them tell me its the Turbo !! Here my last scan : Address 01: Engine Labels: 03L-906-022-CBA.clb
1 Fault Found:
000665 - Boost Pressure Regulation
P0299 - 000 - Control Range Not Reached - Intermittent - MIL ON
Freeze Frame:
Fault Status: 10100000
Fault Priority: 2
Fault Frequency: 5
Mileage: 161037 km
Time Indication: 0
Date: 2013.07.25
Time: 12:57:08
Freeze Frame:
RPM: 2208 /min
Speed: 114.0 km/h
Load: 52.9 %
Absolute Pres.: 1703.4 mbar
Absolute Pres.: 1285.2 mbar
Lambda: 100.2 %
Lambda: 24.5 %
Attachment 21665 Here' a picture of my engine layout hope that helps. There is no 2nd actuator on the inlet manifold as you state but I guess its now a solenoid which controls the throttle type valve from the turbo unit pipe
control range not reached. it is underboost. it could be vacuum actuator leaking on turbo. not sure if audi do they but vw do a repair kit for turbo actuator for around £100 (can't remmeber exact price). bit tricky to replace. but can be done. just plug any vacuum pump to actuator and see if is leaking.
sorry for my poor english
Audi A3: Fault code p0299 - Under boost. Information 2009 Audi a3 Sportsback 130bhp 2.0TDI. CBA engine type Chassis P8
P0299 fault finally resolved. Faulty part being: Actuator failed vacuum.
( Fault code reading given was: P0299 - 000 - Control Range Not Reached - Intermittent – MIL, ON000665 - Boost Pressure Regulation)
Freeze Frame:
RPM: 2208 /min. Speed: 114.0 km/h Load: 52.9 % Absolute Pres.: 1703.4 mbar Absolute Pres.: 1285.2 mbar
Lambda: 100.2 % Lambda: 24.5 %.
I change a few solenoids N75 and checked for leaks on the vacuum pipes leading to the actuator unit etc. Having check the actuator unit for movement it did move on revving the engine which threw me. So I went back to it and doubled checked to see if it held a vacuum; On sucking the pipe to the actuator unit I could suck and suck and it wouldn’t hold a vacuum a simple test with you mouth and tongue over the end of the pipe to see if it held a vacuum. It didn’t.
So having noted on the forum that there is a repair kit for it. (also ebay) I rang Audi spares and they did have a kit costing £125. Audi would also fit it for £130 that being Stoke, as Liverpool Audi dealers want to fault test your car before making a repair that’s £135 for fault finding plus the spare part £125 plus fitting it, they being dearer then Stoke on all repair work, so total bill from Liverpool would be £400ish. Stoke Audi are very helpful as ever, with Tech advice and are cheaper on most if not all repairs then most audi dealers, given I had limited time and Stokes being busy I planned on doing the repair myself.K
Knowing I had a spare part I set about removing the old one as based on the price for replacing it by the Audi dealership obviously meant that it was an hours labour to replace the part, which meant that it must be able to be done by not having to remove the turbo.
Step by Step:
Remove the air filter cover, and pipe work back to the turbo unit unplugging the MAS sensor plug and small vacuum pipe.
Remove the vacuum pipe from the Actuator unit and the electric socket sensor from the top.
Remove the lower large air pipe from the turbo unit TX 30 bolts and jubilee clip.
This gives access to the Actuator bolt/rod and nut. There isn’t much room and it’s fiddly and its best also to remove the engine belly protection cover as you will drop the tools and have to recover them. Spray the actuator rod with WD40 to aid removal.
The actuator is secure by the long tread bolt underneath connecting to the turbo linkage, this nut you have to remove by using a ¼ socket size 10mm long/deep socket as the tread on the bolt of the actuator is long, get a few sockets of different height as its fiddly to get the right size on the nut ( I had to wiz abit off one socket to get it to fit.) and connect the socket without getting it wedge against the exhaust manifold. Once you’re on the nut with the 10mm socket, connect the socket wrench to the socket and untighten it, once its moving you may be able to just use the socket and twist it off with your fingers now, if you put some masking tape around the socket end this will aid your grip when twisting the socket off with your fingers.
Once off don’t worry if you drop the nut as you get a new one with the repairs kit.
Now unbolt the 3 10mm bolts (again you get 3 new bolts) from the side of the accuator until, to aid removal unscrew the oil pipe on top which feeds the top of the turbo unit with a 17mm open end spanner this will give you more access to the 3 bolts.
Now pull the actuator unit off. Now set up the New actuator unit to match the old one, that is the old locking nut distance to the main body must match your old units distance, 42mm in my case. Use the lock tight sealent supplied with the repair kit to hold the new nut in place. ( you can note the wear on the old until by matching the sucking test on both until there’s a massive difference, any doubts are now reassured the old until is faulty if it doesn’t hold a vacuum with your tongue, note the travel difference between the two.)
Now it reverses all the way – refit the new unit ensuring the rod goes into the turbo linkage.
Put the new nut in a small 10mm socket and twist it by hand onto the rode. Then screw the nut all the way to the top and then tighten with the long 10mm socket.
Place lock tight gel on the nut with your finger as access is tight to get the nozzle on the nut.( again the gel is part of the repair kit).
Refit the 3 bolts on the side of the unit.
ENSURE you reconnect the oil pipe with a 17mm spanner. (unlike me and loose £35 of new oil!!!! and clean up)
Reconnect all the large air pipe work and the vacuum pipes.
Reconnect the vacuum pipe to the Actuator and the electric plug too.
You can test the movement of the new accuator by sucking again on the pipe and you will notice fare greater travel of the rode.
Start up the engine, ensure the oil pipe isn’t leaking and all pipe work is refitted double, check.
And road test. A massive difference in performance you will note, I thought I just had the issue at 2200 reves at 70mph but the lack of pull in all gears I didn’t notice until the new until was on and working.
This was a really easy fix and a cheap fix too. It took me 1 ½ hours in total. Then an hour cleaning oil up !!!!!
Tools required:
TX 15, 20, 25, 30 star shape ¼ sockets or bits.
17mm spanner
¼ sockets ( just the right size to gain access 3/8 to small and ½ to large. 10mm long socket and small socket. I did take photo as I did it and will up load once I've put captions on or via youtube. Hope this helps others. Here a link on you tube with photos etc: Audi 2.0TDI actuator fix Fault code: P0299 under boost - YouTube
Hi mate :) ... Welcome to VWAF! :D ..Quote:
Originally Posted by Benoticed
Indeed yours will differ due to:-Quote:
Originally Posted by Benoticed
Which is a newer common rail engine where as the A4 in this thread is older Pumpe-Düse engine ...Quote:
Originally Posted by Benoticed
hi again well was going down motorway and it went into limp mode 4 or 5 times always seems to be in 6th gear at low revs when im climbing a hill anyway had a look today with my brothers d900 code reader po299 turbo underboost last freeze frame
calc load...........................89.01%
coolant temp......................82.0 c
m.a.p................................146kpa
eng speed..........................2190.05rpm
veh speed..........................109km/h
i.a.t...................................31.0c
m.a.f..................................55.95g/s
tps....................................94.90%
so from that can anyone see a problem before i take it to a cliff and roll it over
Hi ifsot,you issue was the same as mine. In 6th gear probably around 2300revs it goes into limp. But around town driving seems ok. Check you have a vacuum on the Actuator above the turbo unit. Disconnect the black pipe at the little black solenoid and suck on the pipe, if you can continue to suck the actuator is broken if you suck and feel resistance hold your tongue over the pipe and see if it holds the vacuum if it doesn't again the actuator is at fault. Search the forum for my issue on a p0299 post in last 3 days. A simple job to do for any DIY fix . £125 for a new actuator from the dealer. and under 2 hours to fix it working from the top of the car only. hope that helps.
hi everybody well had enough of car so i took it to a garage to get it looked at , left it with them expecting a big bill got a call saying actuator above the turbo had been changed before i got car for a new one and who ever had done it had put the boost pipe on wrong way round , the garage could of charged me lots to sort it out he charged me £20 car works great now turbo at full power and no limp mode im happy as larry who ever he is lol the garage if anyone wants to use him is in doncaster deutsche mark google them great place guy really knew his stuff and does not over charge eutsche MarkDeutsche Mark
hi i got the same problem on skoda octavia 1.9 tdi recently had new engine due to not starting start and runs mint having error code p0299 up saying turber supercharger underboost , plus a few other egr system fail and n75 problem wich ive replaced all 3 checked all pipes but can hear hissing as iif air leaking from the ride side of the back of the engine were the n75 and manifold is any help been trying fix this problem for weeks took turbo pipes off turbo spinning freely some times it wants to go and some times no guts in it whats so ever any suggestions ??