PD140 Octavia.

Does anyone else have a lumpy idle, but if you put the revs up a bit it's all ok.

Same with the clutch in or out, so I doubt it's the DMF.

Current thoughts are time to clean the EGR/intake/throttle body.

Suggestions on a post card to... Me

Ta

Mine is a little lumpy during warm-up. It's fine when cold, fine when warn, it's just about 5 mins after a cold start in colder weather (like now), and evens out a few mins later. I just ignore it

This as in shaking or almost like a 'misfire' type issue?

If Yes, solved it with VAGCOM. Lowered the Idle to 800 RPM from 830.

After a Skoda service it became a lot worse. Only happened when engine hot. You could feel the engine shaking from inside the car. Popping the bonnet you could see the engine jumping around.

I had engine mounts checked and even replaced Dog mount on the off change. After having a couple garages say that it was normal or a 'feature' I went to VAGCOM and started with playing with idle.

If no, ignore all that bumpf above

HTH

Indeed it's like the engine is missing a cylinder, although obviously it isn't.

I'm blaming it on making a car breath it's own farts at idle to meet emissions requirements.

Mine does it when hot and if you just touch the revs so it's about 11-1200 rpm it really starts to feels like a misfire. Can feel it through the seat and everything. Any suggestions anyone, obviously lowering the idle wont cut it for me as I notice it more when slightly revving.

I must be lucky then, mine is as smooth as silk!

Mines smooth as well, 90K miles and counting.

I'm blaming it on making a car breath it's own farts at idle to meet emissions requirements.

Think you got it right there.

Give it some Millers

Well I cleaned up the connectors on the MAF (which are gold plated) and put some silicon grease in there before reassembly and the idle seems a lot smoother.

If it comes back the EGR is going to get a proper clean out.

I would suggest to check and clean other engine bay connectors, too, since you bought the grease...

I would suggest to check and clean other engine bay connectors, too, since you bought the grease...

Had the grease from something else and I'll see how things go before I take things apart again.

The whole thing has to come out for a cambelt change soon anyway so it can wait until after then.

Has anyone else experienced an uneven idle, almost as if a cylinder isn't firing and the engine is off balance after a bit of driving at higher (not high, just higher) revs.

I seem to have this occasionally and it seems worse when the fuel tank is below half full and maybe get worse on a steep slope, but I may be imagining these two.

I'm suspecting the lift pump in the fuel tank to be a possible cause, but does anyone else have any suggestions.

I guess the tandem pump could be another option but that's expensive.

The car is a 2.0 PD TDI 140.

Edited 16 February, 201016 yr by cheezemonkhai

What engine is this on matey?

I've found my PD105 to be a little uneven until the engine has warmed up to 90 degrees.

I've not actually encountered what you've said though.

Just a quick question, how long has it been since you've replaced the fuel filter?

Added to the first post but it's a 2.0 TDI

Fuel filter was last replaced 40k miles ago and the interval is 60k.

This has been happening for a while now and I did report it under warranty a long time back. It just seems to gently rock the whole car with an uneven idle, which is IMHO points something to do with fuel delivery on a derv.

Putting the clutch in makes no difference and I'm sure it's not a DMF.

Edited 16 February, 201016 yr by cheezemonkhai

I'm not entirely sure what the problem could be, but i think 40k would be the maximum amount of time i'd personally be willing to leave a fuel filter.

It could be a list of things thought :(

I'd imagine that if it had been the lift pump, then at higher revs it would have started starving of fuel and retarding the fueling and power output.

I've noticed that until my car has got to full operating temp that the engine tends to feel as though its rocking slightly. But that maybe down to a duff engine/gearbox mount i think i maybe suffering with at the moment. I am thinking of putting the original VW coolant temp sensor back in and seeing what that does. As i replaced it with a non genuine one.

My post probably wasn't a great help, but I do hope you get it sorted matey!

At 92k mine was still running smoothly on both idle and fast idle. Fuel filter in mine was changed as per the service interval at 60k, but it was still running smoothly before that.

My 2.0TDI has a new cylinder head, new tandem pump, new injector loom, and new fuel lines and it still has the feeling of an odd misfire every now and again.

Its not always there, sometimes the engine is relatively smooth and sometimes it feels lumpy at idle. I just dismiss it as another crap characteristic of this engine.

Could be the lift pump or maybe a crappy injector and there is no misfire detection on the BKD engine.

I have a few options that are in my mind:

1) Fuel Filter

2) Lift pump

3) Tandem pump

4) injector or injector loom

That's in order of cost. I think I might well ask the dealer to have another look.

It does seem to occur more with the tank below half as I put in 10L to take it over and it has not done it since.

I'll be back bellow a half by tonight, so will be able to tell better then.

This is, to say the least most frustrating.

I'll probably pop VAG-COM on there this evening and measure the injector quantities etc.

Does anyone know the measuring blocks to check this off the top of their head?

Ta

Right well, I plugged VAG-COM in and logged a few channels as shown by the attached spreadsheet.

Something that seems to suggest the wobble is a real one and not just me imagining it is the change in idle speed from 819 to 840 every so often.

Anybody any comments? I'm not so sure the MAF values are following a normal, but I have nothing to compare to really.

I did graph MAF vs RPM, but the new site won't let me upload an XLS or even a CSV, so it's the CSV renames to a .txt

I forgot i created this thread, but I'll try and get a mod to move the thread below into this one.

I've posted some VAG-COM logs there.

http://briskoda.net/...ft-pump-issues/

(Merged threads - Tom)

Mine used to have a VERY rougth idle when first started accompined by hesitation and stuttering. This only happened in warm/hot weather, and went away once the car was warmed up. No problems in cold weather so only noticed it during the summer. Last summer got fed up with it and took the car to the dealers. They said there was an ECU firmware update available and loaded that. Since then its much better when first started even in hot weather, but has a slightly rougth idle all the time even when the engine has fully warmed up. Would take it back in but I've got a new one on order, which should be here in the next few weeks, so I've lost interest .

No the PD 140 in the Octy is fine and smooth... but the pd100 in the Fabia has a lumpy idle in cold weather as it's warming up - it's fine with a cold start and fine once warm but slightly lumpy in the middle. I've been blaming it on the pikey mod to the fuel temp sensor...

Well a bit more work on it today and the rough idle doesn't seem to start until the engine is warmed up. Cold engine and it appears to be a smooth idle.

Temp sender seems to be reading within a small percentage of what it should do too.

Edited 17 February, 201016 yr by cheezemonkhai

And another drive shows that I'm wrong that the car doesn't do it when full of fuel.

It is perhaps a little less obvious, but that could well just be down the the effect of mass damping the car with the extra fuel.

This is getting quite annoying now.

I changed my idle to 800 RPM and this cured the lumpy issue at idle.

Mind you I find driving the car coming on and off the throttle smoother if I have the idle speed at 840 rpm.

Want my log from VAG COM to compare with ?