Hi, for a few months now i have been getting a limp mode scenario normally, but not always, when reaching 60-70 / putting foot down / climbing gradients of varying degrees whist accelerating.

 

The first time this ever happened was when joining dual carriageway off roundabout accelerating quick to about 55-60 in third approx 3,500 revs.

 

Most of the times since have been at around the 3,000rpm mark but once or twice in 4th at 1,500rpm or so. I can pull away as quick as the car will allow in 1st 2nd 3rd upto and a little over 3,000 revs with no limp, it just seems to be at higher speeds and gears?

 

I've read loads of EGR / Limp mode related topics and there are a lot of different reasons and solutions listed.

 

Myself i've bought some EGR cleaner that sprays in the air intake (after taking filter out) and the next day or two the car seemed smoother when pulling away but never got to dual carriageway at first to test it out at 60-70, until a few days later when it wasnt feeling as smooth anymore anyway!

 

I've since had the time to remove the lower egr flap which was a little dirty, but I wouldn't say excessive, comments on that??

 

 

then i was planning on cleaning upper egr piece and intake manifold but stopped as i wanted to get new gaskets before i removed them. The following is a look inside, at the best angle i could get, at the upper part of the intake pipe above the flap.

 

 

it too does look a little dirty but does it look bad enough to restrict air flow??

 

I will post pics once I have removed intake etc in following weeks but and comments on pics so far or suggestions otherwise would be appreciated, or ask if theres anything i have neglected that would narrow down the options on cause / remedy, thanks.

Are you sure it is dropping into limp-home mode?

 

As soon as this happens it should log a fault code but you say there are non saved?

Well by no codes I mean that no engine management light and subsequent code. I only have a basic code reader and not a vag com so can't access any previous logged results. I plan on taking it to a garage next week to plug it in, we will see if any saved log can shed light on the fault.

Meanwhile I have the rear wheel sawtooth ing (one tyre only) issue to remedy! Hopefully the shocker I've just replaced sorts that.

I don't think your problem has anything to do with EGR, as EGR problems on these PD engines don't cause limp home mode, unlike on some of the later CR engines.

 

My car has the same engine as yours and recently the EGR valve stuck closed. No limp home mode on mine, it would still rev to the red line and performed as normal. The only way I knew anything was wrong was the MIL/glow plug light being on and a fault code for insufficient EGR flow when I scanned it (even with a £7 generic scanner).

 

Yours sounds more like perhaps sticking turbo vanes (although they usually overboost rather than underboost), or a clogged fuel filter, or perhaps even a failing MAF sensor?

 

When was the fuel filter last changed?

Cheers nick, I have only recently changed the fuel filter (1,400miles ago) although it was quite black, still it didn't change performance of the car.

I feel that your correct in indicating turbo, I just wanted to eliminate cheaper options first. I also priced up a maf when I was thinking about that, Skoda was £130 or so. I knew cheaper options are available but I would try to go for genuine or at least reputable retailers with oem parts as I rely on the car for work.

I've also read about the maf check, that is, disconnect the sensor and see how the car runs. Needs code clearing after, which I can do. But does this cause any other adverse effects with maf as I read somewhere that when disconnecting/ reconnecting the egr sensor that it blows a fuse? Which could just be because they hadn't disconnected battery to do so??

Thanks.

as per nick's post I think it could be sticky turbo vanes causing it to go into limp mode, you could try some dedicated turbo cleaners such as the ones below that you simply just add to the fuel tank on fill up

 

http://www.powerenhancer.co.uk/section.php/224/1/turbo-cleaners/046a0eb6cb611d8a19e5c0428c4cb81d

Just to clarify, I don't think its actually going into limp home mode. If it was then the engine management light would be on and there would be at least one fault code coming up when scanned. Various faults can cause a lack of power in themselves without the ECU actually going into limp home mode, which seems to be what is happening here.

 

The turbo vanes could be sticking so that there is too little boost, rather than too much, which will make the engine feel gutless but won't necessarily flag up any error codes. This could also be due to something like the turbo actuator vacuum pipe being split for example.

 

I've never heard of unplugging the MAF causing a fuse to blow or causing any other problems, but it will flag an error code as you say. If in doubt only unplug/reconnect things with the ignition switched off.

I would expect a proper limp mode to bring up something on the dash myself but I don't know what else you would call it? When it happens I lose power, car loses speed on motorway on slightest of gradients and is otherwise guttless. But if I haven't reset it (ignition off/on) and I'm back in town the car pulls away swiftly in low revs but refuses to go past 2,500 or there abouts thus being limited by something (I assume turbo shut off in this case?)

I'm going to try and find time Sunday to get underneath and check pipes which you mentioned.

Cheers for replies.

Limp mode without warning lights was fairly common on the mkI.

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I've gone into limp mode without any warning messages on the dash, you can tell as the car feel gutless and does not allow you to rev beyond 2.5k but if you switch the engine off and back on it normally resets itself but vcds should able to identify a fault code such as turbo overboost issue. With a blocked erg you will normally get a engine management light message on the dash.

I must admit I've experienced something like this with my mums old Astra cdti. It would go through phases of only revving to about 2500 rpm, then suddenly clear for no apparent reason and be fine for a while. That never brought the engine management light on or stored any codes. I hadn't heard of this happening with a mk 2 Octavia before though.

I think when you say limp mode you mean there's a brief moment where the car feels as though it has stalled and then instantly starts? I have this on mine, totally irregular but ignore it now.

Mine is the same kind of engine speed in the same gears

Edited 6 June, 201412 yr by o_ptic

I have experienced this and posted about it on here. Mine does did exactly the same as yours, but accelerating up to motorway speed when joining it. I would say that it is not limp mode but that the car is not activating the turbo so you are running on the standard engine with no boost at all, at least that is what mine feels like.

 

Mine did it twice, not long after I got it, but has only done it occasionally since. I was going to try the Mr Muscle engine cleaner trick to see if it sorted mine.

 

It is odd that it doesn't throw the engine management light though, isn't it?

It certainly is, with such a drastic loss of power you would expect it to throw something up.

Well after using different cleaners including turbo and catalytic that go in the tank I haven't had any change.

I used a egr cleaner which you spray directly into the air intake in front of the air filter box (after removing the filter), so it travels though the turbo too, and that seemed to improve things for a day or so.

I have since bought an Innotec turbo cleaner and used that yesterday. There is build up on the blades inside the turbo and this loosened some of it (can't see vanes without dismantling) took for a run, got some dirt to come out the exhaust at first, however car still had its loss of power at the top end.

After driving it about today I would say it feels better than it did but I think further cleaning, maybe a terraclean type might be next.

The only other concern I have at the moment is that I think it maybe an oil seal inside the turbo as the aluminium side of the turbo is wet around the air pipe connections. I'll post the pic later to see what people think.

So this is the turbo pipe on the egr side as it leaves turbo to go to intercooler

 

 

this is the second union after the turbo on the egr side

 

 

thing I notice about most turbo issue pictures is the carbon build up always seems dry, mine seems wet?

The moist oily air from the crank case breather causes the dampness.

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Hello I know this was a wile back but did you get this problem sorted