Limp mode keeps coming back - VW

JAMES VTI S

Took my VW caddy 1.9tdi 2007 to get the EML diagnosed and it was in limp mode.

The code was for the boost pressure solinoid which was replaced and all was good for and hour until limp mode came back after I turned the engine off.

The mechanic cancelled the light again and the same story again all was good followed by limp mode.

He read the codes again and I've attached a picture of the latest codes the diagnostic computer gave.

*The engine has more power

*When I floor it for a while limp mode comes back

*When I turn off/on the ignition while moving limp mode goes away until the engine is switched off or I floor the ACC for a while.

*Any ideas lads, I have the old boost solinoid alsom

listermint

Checked for leaks ?

JAMES VTI S

I wouldn't know where to start, there's so many hoses, pipes.

George Dalton

Wiring issues are common. You need to find someone who is familiar with the problems they give.

JAMES VTI S

How to find a mechanic that is used to these issues?

Steve

JAMES VTI S wrote: »

How to find a mechanic that is used to these issues?

Where in the country are you?

JAMES VTI S

Co. Limerick. But munster is fine I don't mind traveling for the right service.

Steve

JAMES VTI S wrote: »

Co. Limerick. But munster is fine I don't mind traveling for the right service.

Ah, ok, if you were in Dublin, I know a good guy for this, sorry, hopefully someone here knows a more west based solution..

corks finest

Ref limp mode another reason could be a blown brake bulb( my old Skoda fabia went into limp cos of that as it blew something under the brake pedal aswell)

JAMES VTI S

I don't have blown bulbs though. Thanks.

jmreire

I had a 1.9 tdi Audi for a few years, a bit older than your's ( 2003 ) and it started this limp home mode, so I started to put 400 ml 2 T oil into the fuel tank every time I filled it, result. no more limp home modes. The only ever other problem I had with that car was the wiring harness for the injectors is under the rocker cover,,,and they can give problems, mainly mis-firing.... I disconnected the one in mine, cleaned all the connections and replaced it,,,end of problem. It did not show up any problem's either when it was scanned. So maybe worth a try for you? 2 T oil is cheap, get the cheapest you can find,,,, for the injector harness, get some one who know's what he is doing. The harness can be bought separately but are not so easy to fit. Well worth a try cleaning the connection's on it first.

CoBo55

Sticking turbo vanes, had the very same trouble with an Octavia of that vintage. I got rid of it, it's still on the road but I wasn't prepared to pay for a new turbo, which is the only lasting solution.

JAMES VTI S

Ya, about a grand for the turbo I hear...

CoBo55

jmreire wrote: »

I had a 1.9 tdi Audi for a few years, a bit older than your's ( 2003 ) and it started this limp home mode, so I started to put 400 ml 2 T oil into the fuel tank every time I filled it, result. no more limp home modes. The only ever other problem I had with that car was the wiring harness for the injectors is under the rocker cover,,,and they can give problems, mainly mis-firing.... I disconnected the one in mine, cleaned all the connections and replaced it,,,end of problem. It did not show up any problem's either when it was scanned. So maybe worth a try for you? 2 T oil is cheap, get the cheapest you can find,,,, for the injector harness, get some one who know's what he is doing. The harness can be bought separately but are not so easy to fit. Well worth a try cleaning the connection's on it first.

Nothing to do with the injector harness it hasn't any misfiring codes logged, never heard of putting two stroke oil in the diesel before...

jmreire

CoBo55 wrote: »

Nothing to do with the injector harness it hasn't any misfiring codes logged, never heard of putting two stroke oil in the diesel before...

I'm speaking from personal experience with my 1.9 tdi, which had the AVF engine, one of the best 1.9 tdi engines ever produced,,,,another great engine was the AWX.
After I bought it, it would occasionally go into limp mode....so I had heard about adding 2 T oil, and tried it out...never again experienced a "Limp " mode.....not even one in more than 20'000 Miles. Car is still going strong....and still no limp modes happening. The new owner, has followed my instructions re the 2 T oil, and he has not experienced any limp modes either.
The Injector harness has a known fault in that over time, the connections get dirty. That threw a code ok, but it did not specify the harness...I forget what it was now, but it vanished after I removed the harness, cleaned and tightened the connectors,,,, no problem since. I did not even have to remove the harness completely, which not so easy, given the proximity of the bulkhead to the rear of the engine, and the stiffness of the harness itself. Maybe when they are new, they are more flexible, and easier to fit... but mine had 150'000 miles on it, so a bit of hardness in the plastic frame that keep's the harness in place is to be expected. That's very strange that you have never heard of adding 2T oil to diesel fuel.....google it, and see what you find. was a very well tried and true method in keeping the various components lubricated in diesel engines.... friend of mine has as 2010 MB W212, and he swear's by it.....add's a few ML's of 2T every time he fill's it up....now has nearly 200'000 Klms done, and car is driving fine, recently flew through the NCT.

JAMES VTI S

Mine has 337,000k KM's on it, this is its first problem in nearly 10 years of ownership.

CoBo55

jmreire wrote: »

I'm speaking from personal experience with my 1.9 tdi, which had the AVF engine, one of the best 1.9 tdi engines ever produced,,,,another great engine was the AWX.
After I bought it, it would occasionally go into limp mode....so I had heard about adding 2 T oil, and tried it out...never again experienced a "Limp " mode.....not even one in more than 20'000 Miles. Car is still going strong....and still no limp modes happening. The new owner, has followed my instructions re the 2 T oil, and he has not experienced any limp modes either.
The Injector harness has a known fault in that over time, the connections get dirty. That threw a code ok, but it did not specify the harness...I forget what it was now, but it vanished after I removed the harness, cleaned and tightened the connectors,,,, no problem since. I did not even have to remove the harness completely, which not so easy, given the proximity of the bulkhead to the rear of the engine, and the stiffness of the harness itself. Maybe when they are new, they are more flexible, and easier to fit... but mine had 150'000 miles on it, so a bit of hardness in the plastic frame that keep's the harness in place is to be expected. That's very strange that you have never heard of adding 2T oil to diesel fuel.....google it, and see what you find. was a very well tried and true method in keeping the various components lubricated in diesel engines.... friend of mine has as 2010 MB W212, and he swear's by it.....add's a few ML's of 2T every time he fill's it up....now has nearly 200'000 Klms done, and car is driving fine, recently flew through the NCT.

Prefer to follow logic myself... Op has an overboost issue, he changed the boost sensor which was the next logical step but unfortunately the original sensor was working correctly in telling the ECU the boost pressure was too high. Overboost is caused by the turbo vanes sticking in the high boost ( the normal closed position) and failing to open quickly enough to reduce pressure. Can't see that being fixed by strimmer oil... Google overboost although I think I've explained the basic mechanics of how it works, even to a snake oil salesman.

jmreire

JAMES VTI S wrote: »

Mine has 337,000k KM's on it, this is its first problem in nearly 10 years of ownership.

Do you know what engine is in it?? Friend of mine had 2009 Octavia, worked for an agricultural company, load of driving each day had 950'000 Klms when he traded it in, and only then because it failed the NCT...but it was mainly suspension's and brakes etc.that were at fault... engine still starting and running though. Always well serviced, oil and filter changed on time.

JAMES VTI S

I don't? 1.9tdi is all I know??

jmreire

CoBo55 wrote: »

Prefer to follow logic myself... Op has an overboost issue, he changed the boost sensor which was the next logical step but unfortunately the original sensor was working correctly in telling the ECU the boost pressure was too high. Overboost is caused by the turbo vanes sticking in the high boost ( the normal closed position) and failing to open quickly enough to reduce pressure. Can't see that being fixed by strimmer oil... Google overboost although I think I've explained the basic mechanics of how it works, even to a snake oil salesman.

Oh, no need for me to google it,I know well what Overboost is..I'm just telling about my personal experience and what has worked for me....and trying to help some one here on the forum, but if the best you can do is refer to me ( or indeed anyone else )as a "Snake Oil Salesman" , that speaks volumes about you, but not in a good way. If you can't post without resorting to that kind if comment, better not comment at all

Kenny Logins

JAMES VTI S wrote: »

Ya, about a grand for the turbo I hear...

Mr Muscle in the hot side. Check it out on YouTube.

CoBo55

JAMES VTI S wrote: »

Mine has 337,000k KM's on it, this is its first problem in nearly 10 years of ownership.

It really seems to be hit and miss with that engine some get the overboost problem and others do galactic mileages. It's certainly more prevalent in cars doing stop start work and short trips. You could try the recon route but quality varies considerably. George Dalton on here is a top class vag mechanic try sending him a PM ( can't see him recommending strimmer oil though). No matter what it isn't a quick fix unfortunately.

JAMES VTI S

I hear a turbo can take upto a week?

Toyotafanboi

CoBo55 wrote: »

Prefer to follow logic myself...

Thank heavens, I though it was just me.

We have a fairly specific fault code to work with here and yet were talking about adding two stroke to the diesel and checking for blown brake light bulbs. May aswell advise topping up the screen wash and adjusting the rear view mirror too, just encase that helps.

Best advice, aside from the suspected turbo, is to get someone to look at it who is familiar with them.

jmreire

Toyotafanboi wrote: »

Thank heavens, I though it was just me.

We have a fairly specific fault code to work with here and yet were talking about adding two stroke to the diesel and checking for blown brake light bulbs. May aswell advise topping up the screen wash and adjusting the rear view mirror too, just encase that helps.

Best advice, aside from the suspected turbo, is to get someone to look at it who is familiar with them.

We have a Op with a limp mode problem, so he can follow the results of the scan, and do what ever that dictates, at whatever expense..fine no problem. Now I had a similar problem in my 1.9 tdi....and before going down the expensive route ( which at the time, might have been more than the car was worth ) I was a member of the VAG forum, and it seems that I was not the only one to have this problem, and it was recommended that I try the 2T solution, and see what happened, And what happened? I duly added 400 Mls at next fuel filling. And the result?? No more limp home mode. Same thing with the Injector harness.. the OBD threw a code showing injector fault, Clear the fault...everything fine for awhile, then misfiring return's. Sometimes, not for 500 miles, others after 50 Miles. Again, on the VAG forum, the harness was given as a frequent cause of this, and infinitely better than process of replacing a set of injectors...and afterwards, to find that the problem still existed. So I tried the harness first, and it worked, as did adding 2 T oil to the fuel. Now you can think what you like about it, call it witchcraft if you like,,that;s your prerogative, but I'm a believer...and I'm not the only one. It has worked, and is working,so I'm happy. You can run OBD scan's as much as you like, on any make of car, but sometimes, the car will have a fault,,that is not showing up in a scan... customer brings in the car complaining of this or that...fine run a scan, which show's everything is OK, ( of or maybe has an old fault showing, and you clear it )but next week.. customer is back,,same complaint. If you are in the business, you know that this is true.

jmreire

JAMES VTI S wrote: »

I don't? 1.9tdi is all I know??

To find out which engine is in it, you can write down the VIN nr, ( its in the registration ) and google VIN decoder's, enter in your VIN detail's, and everything about that specific car will come up, inc engine type etc. Alternatively, have look
at the plastic cover on the pulley at the front of the engine.....you will see which engine type on that too.... generally 3 letters.

JAMES VTI S

Cool I'll have a look.

ice.cube

jmreire wrote: »

We have a Op with a limp mode problem, so he can follow the results of the scan, and do what ever that dictates, at whatever expense..fine no problem. Now I had a similar problem in my 1.9 tdi....and before going down the expensive route ( which at the time, might have been more than the car was worth ) I was a member of the VAG forum, and it seems that I was not the only one to have this problem, and it was recommended that I try the 2T solution, and see what happened, And what happened? I duly added 400 Mls at next fuel filling. And the result?? No more limp home mode. Same thing with the Injector harness.. the OBD threw a code showing injector fault, Clear the fault...everything fine for awhile, then misfiring return's. Sometimes, not for 500 miles, others after 50 Miles. Again, on the VAG forum, the harness was given as a frequent cause of this, and infinitely better than process of replacing a set of injectors...and afterwards, to find that the problem still existed. So I tried the harness first, and it worked, as did adding 2 T oil to the fuel. Now you can think what you like about it, call it witchcraft if you like,,that;s your prerogative, but I'm a believer...and I'm not the only one. It has worked, and is working,so I'm happy. You can run OBD scan's as much as you like, on any make of car, but sometimes, the car will have a fault,,that is not showing up in a scan... customer brings in the car complaining of this or that...fine run a scan, which show's everything is OK, ( of or maybe has an old fault showing, and you clear it )but next week.. customer is back,,same complaint. If you are in the business, you know that this is true.

Fairly unusual fix tbh, fair play if it worked for you. I wouldn’t get too upset if I was pushing your idea and getting a little backlash from it!

firstlight

Try the Mr muscle on exhaust side of turbo,had similar problem with a Passat
My turbo use to stick from time to time
Hard drive,diptane,2 stroke and egr delete works a treat on the 1.9.have 3 in the family
Good luck sorting it

JAMES VTI S

What happens the blades stick open? Mr muscle I'm guessing the one that foams up

CoBo55

CoBo55 wrote: »

Sticking turbo vanes, had the very same trouble with an Octavia of that vintage. I got rid of it, it's still on the road but I wasn't prepared to pay for a new turbo, which is the only lasting solution.

same as this, i got the turbo refactored and didnt have the problem again.

pricey fix, mine had to be done for other reasons anyway so it wasnt optional

might be worth seeing if theres a cleaning option, but also worth watchin to see if the buildup has taken the vanes in any way off-centre while youre at it, because at that stage youre into big decision territory

corks finest

JAMES VTI S wrote:

I don't have blown bulbs though. Thanks.

K bud just a thought,auto electrician needed maybe

Steve

Ah ffs, mr muscle is for cleaning kitchens and toilets, it's acid based. for feck sake don't ever put it near an engine!!!

corks finest

Ref brake bulbs ,brake light switch also went at the same time on my fabia ,this ALWAYS puts a car into limp mode

jmreire

ice.cube wrote: »

Fairly unusual fix tbh, fair play if it worked for you. I wouldn’t get too upset if I was pushing your idea and getting a little backlash from it!

Thanks for your support ice.cube, but TBH, Derogatory comment's like "Snake Oil Salesman, and uber sarcastic "why not top up the windscreen as a solution" do not add anything to the discussion,,,,and if this is the best Bos55 and Toyotafanboi can do.....it will not exactly encourage people to reply to any poster who has a problem, and is looking for some advice / help. People are trying to be help full, even if they are not expert's, they are writing about their own experiences...if these comment's are not welcome, then restrict all reply's to " Qualified Personnel Only". And see what does for input on Board's.

Re. 2 Stroke Oil
Extract from Baileys Diesel Group:
QUOTE:-
For adding 2 stroke oil,
The Truth About Adding Two-Stroke Oil To Diesel In Modern Common Rail Engines
March 22, 2016 2jzhilux 75 comments
It seems counter-intuitive to be utilising 2-stroke oil in diesel on common rail, low emission vehicles. The actual premise behind adding 2-stroke does carry weight in certain instances. Vehicles equipped with Bosch, Delphi, or even Siemens fuel systems generally don’t need it. Therefore, you’re unlikely to see a significant change in engine performance or noise with the use of 2-stroke Oil in the diesel.
When and how to use the 2 Stroke in Diesel:
However, if you have a 2005-2012 Denso Common Rail equipped system, your vehicle will most likely notice significant changes. You need 2-stroke premixed oil.
Do not use in cars equipped with DPF
UNQUOTE.

The full article can be read on their site. You can also find other site's where 2T oil is not recommended....so in the end, it's up to the individual. Some swear by it, and some swear at it...I'm of the "swear by it" persuasion.
It may seem like an unusual fix, as you say, but it works,( for me, and other's too) and is not as uncommon as people seem to think. The best mechanic's that I have worked with, when faced with a problem ( and even with OBD diagnostics, you can still get problem's ) would be prepared to try sometimes "unconventional " solutions, even if they sounded a bit bizarre at the outset.Any mechanic will know this.
My 1.9tdi showed injectors misfiring, and the Garage I took it to get a scan ( I don't have VagCom / Ross OBD reader) was all set to replace all 4 injectors...@ €200+ per Injector plus fitting and VAT. But I removed the car and tried the harness instead. So while the OBD scan showed misfiring, it did not pinpoint the actual cause, which was the wiring harness. Removing it and cleaning the connections ( as advised on the VAG forum ) worked, and is still working.
Had I given the green light to go ahead and replace the injectors...it would have solved the problem, not because of the injectors, but in replacing them the harness would have been removed, and refitted, and this alone may have cleaned the connections....but we would never know then, would we? I wonder just how many jobs have been done on vehicles, where the fixing was "accidental"??? Interesting question.

HailSatan

Is the blown bulbs thing an urban legend thing or what? I've heard it before but haven't seen it myself.


I thought oven cleaner was a common DIY egr cleaner. Has that been superceded now since Steve is so dismissive?

Orderofchaos

Don't go solely by the codes. My car was giving me turbo actuator errors, usual response from non specialists would be to replace the actuator then try replacing the turbo. A little bit of research with knowledgeable people and I was directed to clean the Map and Maf sensors which have permanently fixed my issue.

Toyotafanboi

jmreire wrote: »

I had a 1.9 tdi Audi for a few years, a bit older than your's ( 2003 ) and it started this limp home mode, so I started to put 400 ml 2 T oil into the fuel tank every time I filled it, result. no more limp home modes... So maybe worth a try for you?

jmreire wrote: »

Thanks for your support ice.cube, but TBH, Derogatory comment's like "Snake Oil Salesman, and uber sarcastic "why not top up the windscreen as a solution" do not add anything to the discussion,,,,and if this is the best Bos55 and Toyotafanboi can do.....it will not exactly encourage people to reply to any poster who has a problem, and is looking for some advice / help. People are trying to be help full, even if they are not expert's, they are writing about their own experiences...if these comment's are not welcome, then restrict all reply's to " Qualified Personnel Only". And see what does for input on Board's.

There's no issue with replying, but there's also no issue with questioning the replys.

I'm just wondering how adding 2 stroke oil to his diesel will fix a persistent overboost fault?

It wont. Unless I'm missing something and you can explain how it will?

I know it used to be recommended to do this as the additional lubrication from the 2 stroke was intended to aid the longevity of fuel pumps and injectors and the likes but surely adding an additional oil to the diesel also causes more soot and carbon in the exhaust which would in all likelihood make the OP's potential exhaust vane issue worse, not better?

You used it and it didn't harm the car and that's great, but personally I cannot see this doing the OP any good service whatsoever.

corks finest

HailSatan wrote:

Is the blown bulbs thing an urban legend thing or what? I've heard it before but haven't seen it myself.

Google it reference fabia- happened to me , combination of brake light switch and blown brake bulbs put it into limp mode - my auto electrician changed the brake light switch in 10 seconds,I replaced bulbs in 2 minutes+ job done

Kenny Logins

Steve wrote: »

Ah ffs, mr muscle is for cleaning kitchens and toilets, it's acid based. for feck sake don't ever put it near an engine!!!

In the exhaust side of the turbo, not in the engine.

Kenny Logins

HailSatan wrote: »

Is the blown bulbs thing an urban legend thing or what? I've heard it before but haven't seen it myself.


I thought oven cleaner was a common DIY egr cleaner. Has that been superceded now since Steve is so dismissive?

My A6 wouldn't drive with a gammy brake light switch. Not sure what exactly was going on but it felt like a fuel pump cutting out.

Oven cleaner is fine on exhaust parts, but not sure I'd risk it on an EGR directly.

vandriver

'Mine has 337,000k KM's on it, this is its first problem in nearly 10 years of ownership'

Do you run a business?

my3cents

HailSatan wrote: »

Is the blown bulbs thing an urban legend thing or what? I've heard it before but haven't seen it myself.


I thought oven cleaner was a common DIY egr cleaner. Has that been superceded now since Steve is so dismissive?

Engine light comes on on my old VW Polo if there is a blown indicator bulb Took me a while to work that one out :rolleyes:

my3cents

OP has anyone popped open all the electrical connectors in the circuit that controls the component that was replaced?

I had an issue that went on for ages that turned out to be corrosion on the contacts inside one of the connector blocks.

What seemed to happen was engine light would come on I'd take a look at the component that was listed on the diagnostic tool and in the process move the connector block that was causing the problem. Doing that obviously did enough for the contacts to work again for a bit. Rince repeat for a good few times until I followed the loom through and found the main connector block had 2 contacts covered in corrosion. All I did was flood them with switch cleaner and push the connector on and off a few times, now its OK again.

ice.cube

This is one of the strangest treads I have seen 😂

jmreire

Toyotafanboi wrote: »

There's no issue with replying, but there's also no issue with questioning the replys.

I'm just wondering how adding 2 stroke oil to his diesel will fix a persistent overboost fault?

It wont. Unless I'm missing something and you can explain how it will?

I know it used to be recommended to do this as the additional lubrication from the 2 stroke was intended to aid the longevity of fuel pumps and injectors and the likes but surely adding an additional oil to the diesel also causes more soot and carbon in the exhaust which would in all likelihood make the OP's potential exhaust vane issue worse, not better?

You used it and it didn't harm the car and that's great, but personally I cannot see this doing the OP any good service whatsoever.

The OP had limp home problem, and had a scan done. Scan showed boost problem, New part fitted,, worked for awhile, then stopped. OP asked for advice.
I had a limp home problem too, and explained what cured it in my car, I never claimed it was a definite fix for the OP's car, but for the sake of €5 worth of 2T oil, maybe it was worth a try,,what did he have to lose??
I used it for the last 20'000 Miles that I had the car before I sold it, present owner has at least another 20'000 miles done,,,and still no problem's that you describe IE sticking vane's etc.

Replying to a reply, is one thing...no problem there, Board's is meant to be a discussion forum, but rubbishing a reply , as you did is not acceptable., and even more so from a MOD.

For more details about using 2T oil in diesel engined car's, have a look at:- https://www.baileysdiesel.com

CoBo55

jmreire wrote: »

The OP had limp home problem, and had a scan done. Scan showed boost problem, New part fitted,, worked for awhile, then stopped. OP asked for advice.
I had a limp home problem too, and explained what cured it in my car, I never claimed it was a definite fix for the OP's car, but for the sake of €5 worth of 2T oil, maybe it was worth a try,,what did he have to lose??
I used it for the last 20'000 Miles that I had the car before I sold it, present owner has at least another 20'000 miles done,,,and still no problem's that you describe IE sticking vane's etc.

Replying to a reply, is one thing...no problem there, Board's is meant to be a discussion forum, but rubbishing a reply , as you did is not acceptable., and even more so from a MOD.

For more details about using 2T oil in diesel engined car's, have a look at:- https://www.baileysdiesel.com

The new part fitted made no difference as the original part was correctly telling the ECU there was too much boost. Please please stop with the strimmer oil rubbish you're doing my bloody head in at this stage.

jmreire

CoBo55 wrote: »

The new part fitted made no difference as the original part was correctly telling the ECU there was too much boost. Please please stop with the strimmer oil rubbish you're doing my bloody head in at this stage.

Simple solution then, don't read my post's and I'll return the favour, OK?

jmreire

jmreire wrote: »

Simple solution then, don't read my post's

or run a bit of 2T oil through them

CoBo55

The brake light switch plays an important role in sending information to the ECU, if it goes wrong the ECU thinks you are braking and cuts fuel. The driver keeps pressing the accelerator, ECU can't understand what's going on and puts everything into limp mode. A faulty stop and tail bulb can cause exactly the same symptoms, I had that problem in an early B5 Passat ( wrong bulb fitted by dumb mechanic)

jmreire

Deleted User wrote: »

or run a bit of 2T oil through them

Yeah...it will work wonder's..... but only the chape stuff, mind.... :D:D