Limp mode / lack of power

[danielintheuk]

Hi all


I have posted this up before but not had much of a response, so thought i`d try with a different heading.

I have a 1997 passat 1.9 TDI 110 BHP

I am experiencing an intermittent problem where the car loses power, I can not figure out what triggers this to happen, and am unclear on what makes it work again. Sometimes turning the car on and off solves it, other times the car can be left for hours and still have the fault.

The only way I can describe the fault is the power seems to be limited, so i`m guessing its some kind of limp mode, there is no smoke coming from the exhaust , there is no nasty noises, the car still runs smooth , just takes forever to accelerate. Fot instance if I try to accelerate as hard as possible at 60 mph in 4th gear, i`m still getting 40mpg. Whereas when the fault is not present the mpg drops to the teens.

I have checked the air filter, and the vacuum hoses, all look fine. I have removed the MAF , and it looks clean. I have not tried disconnecting the MAF and driving , as I expect this will log a fault code which I dont want at this point.

The car is going to the garage on sat morning, so I will post again to say what was found , and hopefully to say what fixed the problem. As I can see a lot of posts concerning this subject i`m hoping this will help some of the folk on here.

The reason i`m not disconnecting the MAF is I dont want the garage to be fixated with some fault code saying the MAF has been disconnected.

On one of my other posts, someone mentioned turbo may be on its way out. Is this possible considering that the problem is intermittent, I would expect a shot turbo to be a permanent problem. Also there are no strange noises. And the car does pull well when the problem is not happening.

Any advice /replies appreciated.


Thanks

Dan

[ad4pm]

Sounds similar to the problem on my A4 1.9tdi 110 '97 and I ended up with a new turbo fitted. I had no smoke and it did seem ok after a restart only to happen again when putting my foot down hard on steep hils.

I wouldn't say for definite it wasn't a valve or sensor associated with the turbo, but i was lucky and had a warranty which did cover the turbo, so i didn't question the exact cause.

Fingers crossed for you.

Paul

[Eshrules]

hi and sorry if you're first thread didnt get much attention, thats not usual for this website

secondly, i think ill try and get a sticky done on this subject as it tends to crop up a lot.

hesitancy or a lack of power can be one of a few things, now i hope your listening LOL :

the turbo can be responsible, or one of the associated components, such as the vane acutuator, sometimes the EGR (exhaust gas recirc) valve, hoses or the actual vanes of the turbo. my turbo demonstrated similar symptoms to how you describe, shortly after it was replace under warranty. normally, if its associated with the turbo, you will not notice anything until higher in the rev range, around 2200/2300rpm, as this is when the turbo kicks in, will usually overboost and go into limp mode. if this is the case, a fault code will have been logged stating overboost or something like that.

there is a possibility it could be the MAF, usually if its the MAF, you will notice a certain 'jerkiness' through the rev count, not a limit of power. the car does not usually enter limp mode if the MAF is faulty,just runs like a bag of screws. the usual way to check this is to take the MAF off and run the car without it. if the car runs any better, your maf's pooped.

try taking a look at this thread : https://www.vwaudiforum.co.uk/forum/s...ht=turbo+fault

https://www.vwaudiforum.co.uk/forum/s...ighlight=turbo

may offer you some information, i have another thread somewhere with quite a few posts, ill put it on here when i find it.

[ad4pm]

Thinking back 5 years when my problem occured, I seem to remember overboost mentioned by the tuning specialist who eventually were appointed by the warranty company to replace the turbo.

The diagnosis was done by the main VAG dealers in Sheffield.

[docman07]

Hi. I've just read your posting and it sounds exactly like my problem

I bought a Passat TDI 130BHP PD Y-Reg(2001) 10 months ago. It had 120,000miles on it then. It started to lose power after a few months so I changed the Air mass meter(I bought a reconditioned one with 3 months warranty). It drove like new for about 3-4 months then started to lose power again.

I have now bought a Bosch MAF sensor from Eurocarparts with a 1 year warranty but it hasn't made a difference. It has nearly full power when started in the mornings but when it gets to about 2300-3000revs or at speeds of about 70mph the power suddenly drops off and I find it difficult to hit speeds of 75mph. Accelerating becomes V-E-R-Y S-L-O-W at this point and I find it difficult going up hills. The power seems to come back temporarily if the engine is turned off again for a few minutes.

I have also noticed that the temperature gauge refuses to work intermittently.

I took it to a garage and after doing diagnostics for £52 they said it was the turbo wastegate.They have said they can recitfy the problem for £250 without me having to buy a new turbo.

I got some advice from a different forum and I am now waiting to have further diagnostics done on monday with Vag-com reader.

My suspicions are it might be the Pressure boost Valve /solenoid. Some other guy had similar problem and sorted it out by changing this. I think its also called the charge pressure control valve

Keep me posted please.



Docman

[Eshrules]

Hi. I've just read your posting and it sounds exactly like my problem

I bought a Passat TDI 130BHP PD Y-Reg(2001) 10 months ago. It had 120,000miles on it then. It started to lose power after a few months so I changed the Air mass meter(I bought a reconditioned one with 3 months warranty). It drove like new for about 3-4 months then started to lose power again.

I have now bought a Bosch MAF sensor from Eurocarparts with a 1 year warranty but it hasn't made a difference. It has nearly full power when started in the mornings but when it gets to about 2300-3000revs or at speeds of about 70mph the power suddenly drops off and I find it difficult to hit speeds of 75mph. Accelerating becomes V-E-R-Y S-L-O-W at this point and I find it difficult going up hills. The power seems to come back temporarily if the engine is turned off again for a few minutes.

I have also noticed that the temperature gauge refuses to work intermittently.

I took it to a garage and after doing diagnostics for £52 they said it was the turbo wastegate.They have said they can recitfy the problem for £250 without me having to buy a new turbo.

I got some advice from a different forum and I am now waiting to have further diagnostics done on monday with Vag-com reader.

My suspicions are it might be the Pressure boost Valve /solenoid. Some other guy had similar problem and sorted it out by changing this. I think its also called the charge pressure control valve

Keep me posted please.



Docman

i highly doubt its the wastegate, as is what the other forum has advised by the sounds of it. likelyhood being its something to do with the sticky vines on turbo, VNT mechanism or EGR valve. if either one of these begins to function improperly, you will experience turbo problems. a session on the vagcom should help point in the right direction

[danielintheuk]

Hi people

Thanks for the replies

So we have narrowed it down to :-

waste gate
Maf
vanes
Vane actuator
egr valve
hoses
turbo
Charge pressure control valve


Quite a list

I will definitley be updating this post to say what happened.

I`m now worried as my warranty states it covers £300 per item , if I need a new turbo £300 will not buy a turbo

As I bought the car only 2 weeks ago, and problem was reported to them after a few days of owning the car, would the garage have any responibilty to put this right other than the warranty?

Thanks again

Dan

[Eshrules]

Hi people

Thanks for the replies

So we have narrowed it down to :-

waste gate
Maf
vanes
Vane actuator
egr valve
hoses
turbo
Charge pressure control valve


Quite a list

I will definitley be updating this post to say what happened.

I`m now worried as my warranty states it covers £300 per item , if I need a new turbo £300 will not buy a turbo

As I bought the car only 2 weeks ago, and problem was reported to them after a few days of owning the car, would the garage have any responibilty to put this right other than the warranty?

Thanks again

Dan

LOL this is another area of expertise for me, having had the exact same problem as yourself... allow me to explain...


i bought my golf GT TDI from D**E Motor Company in stockport. 2 days later,going down the m.way, i changed gear to find no power (turbo had overboosted and gone into limp mode). panic as anybody would really, i pulled on the hard shoulder, turned the engine off and left it for ten minutes, phoned the dealership to warn them i was coming back and set off again. the car seemed to run fine once restarted (no longer in limp mode). i got to the dealership and after 3 wrong diagnosis sessions (each a week apart) they decided to put a recon turbo and a new MAF on there. this was not done under warranty.

bit of info for you... if the warranty decides that the fault was present when the car was sold, they will not pay out... the responsibility then lies with the trader (unless they told you of this fault before hand which i doubt)

so basically, dont worry about claiming through the warranty, in fact, i wouldnt even try. get the dealer to take the car, fix it and then return it, 2 weeks down the line and a major component failure, you would have every right to request a refund should they refuse to repair free of charge.

[danielintheuk]

Update :-


Took car in this morning, they are keeping it in to fix it. They have given me a bmw 318 compaq to use in the meantime...... I dont like it !

Should hopefully have more news on monday so will keep you all updated.

Cheers

Dan