Revs dropping, car juddering - MK4 Golf 1.6

parking_question_chap

If its also at idle I would suggest you get the hoses looked at, a good indi dealer should be able to do a smoke test.

Edit, just a thought, how old is the battery?

JustAnotherSaver

Right this one is going to be a long shot but for those in the know what do you think? .......

A couple days ago i took the throttle body off the car & gave it a good clean since i was also doing the same to my car too. It wasn't overly dirty & i wasn't doing it in relation to this problem but i figured i'd just clean it as part of general maintenance anyway.

I had the cover off the header tank & on the underside of the cap & around the rim was what i can only describe as sand.

Now the thing is it was only last year that i renewed the header tank because the original one was that bloody filthy that i wasn't even going to attempt to clean it. You couldn't see the water, it was so brown & filthy.

I flushed water right through (clean water direct from tap through garden hose). Took the hoses off the radiator, flushed from top, from bottom & kept at it until it ran really clean. Got the water up to temperature, drained off & continued to flush through & repeated until it was constantly clean.

I then fitted the new tank & put in the G13 coolant with the recommended quantity.

I guess that sand (or whatever it is) isn't just running through the radiator, it's running through the engine too.

This wouldn't be linked in any way to this issue would it?

parking_question_chap wrote: »

If its also at idle I would suggest you get the hoses looked at, a good indi dealer should be able to do a smoke test.

Edit, just a thought, how old is the battery?

Sorry so long for a reply, i've only just seen it.


We got the car maybe around April 2015 so it's at least that old. I've got the feeling (sorry if i'm wrong) that the battery is a long shot kind of thing?

We have an independent mechanic that we go to. He's been off leading up to Xmas so we'll have to get it booked in with him.

I THINK i know where the MAP sensor is located and i THINK i could change it myself.
However if i'm right in where it's located then the dipstick housing & a bit of other cabling is blocking direct access & i don't know how i'd go about getting to it with this stuff in the way. I don't want to try & force it (dipstick housing etc) out of the way in case i shouldn't be doing that & it breaks.

JustAnotherSaver

Well this progressed further tonight.

My car is in at the garage tomorrow so we went down to drop it off & on the way back as we're about to turn on to our street my wife tells me the car has died.
It had been doing its usual juddering on & off, no more or different than usual (& it doesn't happen on EVERY journey).

But at the point of it dying there were no signs of it dying. The first she noticed was when she went to turn in the power steering had gone. Look at the dash & the battery light is on. It was only the fact that we had momentum that we were able to roll down to our house.


The mechanic asked if there's anything specific that will trigger it so he can see it in action but unfortunately there isn't. The car makes its own mind up when it does it.

So he said he doesn't want to just take money off us as he changes everything when it may not even be the thing/s he's changing, but he'll still take a look obviously.


If the car comes back with nothing changed then obviously it'll be no different & it'll have to go. So far it's only been juddering but actual cutting out now? It'll have to go.

parking_question_chap

Ah right

My Golf did that a few times, turned out the regulator was goosed.

Could well be either that or an old battery.

JustAnotherSaver

parking_question_chap wrote: »

Ah right

My Golf did that a few times, turned out the regulator was goosed.

Could well be either that or an old battery.

What's the regulator?

And also the battery is only around 12 months old. I'd forgotten we bought one from Halfords last year. My wife reminded me about it tonight. I think they have them marked up as something like 1 year, 3 year, 5 year battery or something to that effect. Not that i take it as gospel but it was one of the longer lifespan batteries we picked up if i remember right.

RickRastardly

If the car wont fire up at all then now is the time to connect the VAGCOM as the fault wont just be stored, it will be an active fault, in a weird way this is better because a fault that is present and current can be fixed more easily that one that is intermittent like what you had, it has now simply progressed.

JustAnotherSaver

I thought that.

Which is why i told my wife not to knock the ignition off & hold there while i nip in & get the VAGCOM.

Plugged it in .... no new codes. The usual radio code, heated mirror code & nothing in the engine section where MAP sensor was previously thrown up.

RickRastardly

That's interesting, I was just thinking that its unlikely to be the MAP anyway, I think its unlikely the engine would cut out, I think it would simply go into a 'limp home' mode with the engine light showing.


Does she start up again?

reddwarf2002

OP why don't you try and disconnect the MAP sensor (electrical connector) and see if you encounter the same problem? The car should still run using the other sensors.

JustAnotherSaver

RickRastardly wrote: »

That's interesting, I was just thinking that its unlikely to be the MAP anyway, I think its unlikely the engine would cut out, I think it would simply go into a 'limp home' mode with the engine light showing.


Does she start up again?

Yeah. Once i'd finished scanning it i went to start it up & it started first time.

reddwarf2002 wrote: »

OP why don't you try and disconnect the MAP sensor and see if you encounter the same problem? The car should still run using the other sensors.

Back to my question regards the location.

I've posted photos of where i think it is but IF it is there where i show in the photo then i can't get to the thing. The dipstick housing is in the way. I don't want to force it out of the way & create another problem by breaking something.






We were thinking of asking the mechanic to just go ahead & change the MAP sensor, do SOMETHING because if nothing is done then it'll 100% continue.
But you think it's not the MAP sensor based on tonight? So i don't know.

We don't want to but we're edging closer to selling the thing, part exing it, whatever. There's just no confidence in it now whatsoever.