What to do with my Polo (long rambling post)

jumbone

I've got a 2002 1.2 polo 9N and its wrecking my head.

I was driving it with an emissions light coming on and off for a couple of weeks after I got it before I got it looked at. I know they are reknowned for eating coils and figured it was running a bit rich cos not all the fuel was burning. Also the backbox was looking rusted and I figured maybe the rich smell I was getting was partly a leak

Got it looked at and the mechanic told me that it was indeed misfiring but that it was an electrical problem and that the coils were fine and so was the exhaust, just the outer skin rusted. I was satisfied with thisas I knew tthe last owner had just replace one of the coils. Made plans to keave the car round to get wiring sorted in a week or so. After a week the car went to limp mode (not pimp mode as autocorrect thought) so i left it in. Came back to be told after having a look that the misfire had done damage and valves needed replaced on one cylinder. I decided to go for it and get the timing chain done at the same time (it has 90k miles on it). When I went back it wasnt ready as theyd built the engine back up but didnt like how it was running and that the oils wasnt circulating properly. The garage had agreed to sort it with no extra labour cost so I got it back a day or two later with the all clear.

I got the emissions light again and they told me it had a code stored for a temp sensor and that they hadnt replaced it as they wantes to clear it and see if it came back. Fair enough says I but as they told me it was fine to drive on I did. I needed the xar for work and arramged tfor them to take it in while I was on holidays to get everything sorted. During this time it was a bit smokey (blue) and they had agreed to sort the oil burning free of charge as id already paid the labour for the valve job and it was caused any them rebuilding afterwards (No smoke previously). Kept usimg the car as the mechanic told me itd be ok for a week but to stop if it used any water at all which it didnt. Durimg this week the oil ligjt came on and when I topped it up it still kept chiming when I started the car.

Then I went away leaving them access to the car for 12 days to sort the niggles ( te, p sensor, oil consumption and possinly oil sensor)
Just got it back and am told that the temperature sensor was replaced, yhe oild burnin should be sorted and that they had another 1.2 polo in over my holiday and tried its oil sensor on my car which didnt solve the issue. They also changed the plugs as I had 2 the same brand and an odd one.

Went on my way and then after driving only 20 miles I noticed it still being a little smoky and to put the icing on the cake, I got an emissions light on my way home from work.

What should I do? The garage dont seem to be trying to rip me off and they have a good reputation. They didnt need pushed to agree to the no labour costbto sort the issues since the first job and dont seem to be throwing parts at it as they could have easily sold me an exhaust when I thought I had a leak and could have buy a oil level sensor. However despite this my patience is wearing thin - im sure they want rid of me and wouldnt half ass the job as I'll keep coming back ( I live 500m from the garage) and asking to have it sorted with no labour charge.

Should i pay up to get it looked at elsewhere? Hound them to fix it for free?

Also, the car was bought for 1350 pounds and I paid 570 for the valve job, timing chain and oil/airfilter service with the understanding that itd be sorted for another 30k miles at least. I then paid 42 pound for 3 new plugs and a temperature sensor. Im not really looking to spend any more cos the total spent is more than the car is worth. I rationalised it by saying better the devil I know but i have to draw a line somewhere!

As a matter of interest, what do you reckon the car could fetch if I did decide to cut my losses?

Its a 2002 1,2 3 dr polo e, gunmetal grey colour (non metallic), partial service history up to 60k (90 odd on it), receipts showing its just had valves done, chain replaced amd oil, filter and plugs replaced. Also has a half decent head unit and a set of 15 inch dezent alloys.

Toyotafanboi

id throw one last burst of cash at it with another garage.

your garage sounds crap. potentially liars too.

a wiring problem causing a misfire and he was "re-wiring it"... re wiring what exactly?

who strips down a whole head and replaces the valves on just one cylinder and not the other two.

who replaces one coil and one spark plug and not the other two?

i can also damn near guarantee that they didn't take the oil pressure sensor off a customers car while you were away and fit it to yours.

he said he'd sort out your oil burning for free? a free head or bottom end rebuild? where is this garage, i must go there? i'd say he just threw a bottle of snake oil in the engine.

all poor practise.

those polos are pretty crap. if you weren't after throwing €1k in repairs at it i'd say to advertise it for a little less than what you paid and get shut of it. seeing as you are so financially involved with it however, i'd go with one last roll of the dice with a different/ better mechanic. your current one is either very incompetent or a very bad liar.

edit: we had one of those polo's for years. it was a 07 that we got in 08 and had until this year, so we owned it most of it's life. it was well looked after but it never ran right, was always misfiring a little and was quite fond of oil, despite this the emissions were always in check come NCT time.

jumbone

I'm not sure what to think about the garage tbh. I see where you are coming from but I do actually believe him!

I dropped in the day before the car was meant to be ready after the valve job as it's only at the bottom of the road and they had the head off and all the ancillaries. When I had to get it the next day (Friday) it was all built back up but they weren't happy to let me take it as it hadn't been run.

I let them at it an on monday they told me they weren't happy with it after it was run and I saw it all stripped again so they definitely had two cracks at it. The gaffer told me at that point that the job was costing him money labour wise but that he'd honour the "worst case" price he'd given me for the valve job at the outset. And in fairness he did only charge got parts on the plugs and temp sensor.

When I was in telling him it was smokey he told me they had another polo in for the same job which I saw. Until you mentioned it I didn't doubt that.

As for replacing one plug and one coil, the chap I bought it off top me he'd replaced one coil and it was the garage who told me I had an odd plug which I didn't doubt after the seller only replaces one coil.

Since it went into limp I've been dealing exclusively with the boss and not the guy who told me the misfire was an electrical problem. That's not to say he hasn't worked on it though I suppose..

As for selling it, I'm in belfast if that makes a difference to what you think it would fetch. Obviously I'd be the dodgy private seller saying how it's just had loads of engine work done but it's sold as seen...

jumbone

For what it's worth, he told me to consider replacing all 3 coils when I had a few spare pounds. He said he couldn't tell if the one changed before was oem or not and that the last chap could have even got it from a scrapper car. He quoted me 25 pound each for Bosch coils which seems fair. I presume the labour would be half an hour tops

edit: we had one of those polo's for years. it was a 07 that we got in 08 and had until this year, so we owned it most of it's life. it was well looked after but it never ran right, was always misfiring a little and was quite fond of oil, despite this the emissions were always in check come NCT time.

It passed the mot the day before I bought it well inside tolerances

CO - idle. 1.13% (limit 3.5%)
HC 992 ppm (1200 ppm or less)

I reckon the previous owner knew it was a lemon and threw a coil and a plug in the bad cylinder and cleared the codes before the mot and shifting it on to me. I dropped the ball and took him at his word he had it months and didn't check the v5, when I got my copy I realised he had it a few weeks before flipping it. I knew he sold a few cars from googling the phone number so I thought nothing of it, that he's entitled to his profit for taking the risk you know.

If I thought it had a snowballs chance of getting an mot next year I'd put up with it till then and then try and break even or just lose a few hundred on it.

Btw I reckon you had a 9n3 not a 9n. It's a facelift but I think same engine. My engine code is azq I think

Toyotafanboi

yes, ours was a 9n3, but bar some cosmetics it's the very same car as the 9n afaik. if the car is driving all right despite the light being on and you were comfortable with the idea you could just drive it into the ground until it gives up completely and sell it for parts or whatever. but car + work at this stage is over €2k if i read your post right which is a fair bit to just walk away from imo.

imo you're still being given a line or your mechanic is crap. i'd get a second opinion from someone else, a competent independent, perhaps a VW specialist.

even if the second opinion only confirms that you should get shut of it, at least you'l have paid a price and gotten a definitive outcome.

no need to be a dodgy seller, if it does come down to it, think of a fair price for the car in its unwell state and advertise it honestly. if the price is right, there'l still be interest in it.

second opinion is a must. you brought your car in to this mechanic with an emissions problem. your mechanic has "replaced" a host of sensors, "re-wired" something, "rebuilt" your head and serviced the car all at your expense and you still have an emissions problem.

Dartz

Possibly a loss of compression somewhere. Has it been compression tested? If compression's low it could be valve seating, or it could be worn piston rings or bore - especially if they start letting oil into the combustion chamber. Has it started to burn oil?

Also, injectors might be sticking and overfuelling.

jumbone

Toyotafanboi wrote: »

second opinion is a must. you brought your car in to this mechanic with an emissions problem. your mechanic has "replaced" a host of sensors, "re-wired" something, "rebuilt" your head and serviced the car all at your expense and you still have an emissions problem.

I'm not the most mechanically minded so forgive some of the **** talk haha. I will make your point though when I go back to them that I've spent so much with no result so far.

I'm thinking I'll give them one more shot at getting it nearly right. I.e. If it runs with no light, a bit smokey the oil consumption is manageable

Nothing was ever actually 'rewired' either btw. I was told it was a minor electrical problem which could be anything I suppose (coils, plugs, leads, sensor). I drove on with the intention of getting it fixed later but by the time i brought it in I dealt with the new guy and he said valves needed doing. I sorta took him at his word and thought tough titty for driving with a misfire.

One thing I did notice though is that the emissions light is the standard engine shaped light that I always thought was the CEL. The engine management light is one that says epc. Obviously a misfire will lead to running rich but possibly it's now not misfiring and actually has an exhaust issue.

My dream solution would be a second opinion telling me that all the work was necessary, replacing a cheap exhaust sensor and the oil consumption and oil level sensor both coming from something stupid like a missing washer where the sensor goes into the sump! Doubt that'll be the case somehow haha

Anybody able to recommend a good vw specialist in belfast?

jumbone

Dartz wrote: »

Possibly a loss of compression somewhere. Has it been compression tested? If compression's low it could be valve seating, or it could be worn piston rings or bore - especially if they start letting oil into the combustion chamber. Has it started to burn oil?

Also, injectors might be sticking and overfuelling.

There was a compression test done on the engine. 2 cylinders were fine but the one with the misfire was down on compression. Can't remember what was said but I seem to recall him saying 60% compression?

Is there a such thing as oversized piston rings for cylinders with a bore bigger than tolerances? Would something like that be a big job

Renegade Mechanic

Hi op, 3 cylinder engine was it?

jumbone

Renegade Mechanic wrote: »

Hi op, 3 cylinder engine was it?

Yup 3 cylinder 1.2 litre 12 valve

Renegade Mechanic

jumbone wrote: »

Yup 3 cylinder 1.2 litre 12 valve

They're infamous. Cylinder three, Exhaust valves. They burn out so badly that on the compression stroke, the air fuel mix just flows past the wrecked valve. The problem is that the mix is still ignited and explodes down the exhaust manifold, superheating and usually damaging the oxygen (O2) sensor and the Catalytic Converter.

The lack of compression is precieved as a misfiring by the ECU which throws up a fault.
Normally (and rightly, as theyre rather prone) Mechanics replace coils but when they dont fix the problem, a further diagnosis reveals low compression on a cylinder.

Que your situation whereby the engine is dismantled and the Head repaired, new gaskets, valves, etc. The big, and poorly understood (by both customers and Mechanics alike) problem is trouble had after the job. The O2 sensors and Catalytic Converter can fail after the job for the points mentioned above. Its a very bitter pill to swallow but a common one nonetheless..

Lastly, oil burning problems, to me, suggest two things.
1: That the valves were installed, but without installing new valve stem oil seals. Again, a burning air/fuel mixture will superheat the valve its flowing past, conduction will take that heat all the way up the valve stem, hardening and compromising the oil seal. Oil will soon leak past and down the valve stem where itll be burned within the exhaust system, even at normal temperatures.

2: New seals were fitted but damaged during valve installation, leading to same problem as above.

jumbone

jumbone wrote: »

It passed the mot the day before I bought it well inside tolerances

CO - idle. 1.13% (limit 3.5%)
HC 992 ppm (1200 ppm or less)

That's well out of any acceptable tolerance for a post 1978 car. Also the high idle measurements are not provided which definitely are required for a 2002 car.

In Irish test the CO idle should be less that 0.50. HC has no limit on idle but on high idle it should be less than 200ppm.

For a comparison, on my '00 car the lastest measurements were:

Idle
CO: 0.01%
HC: 10ppm

3000 rpm:
CO: 0.02%
HC: 11ppm

See the difference?

jumbone

samih wrote: »

That's well out of any acceptable tolerance for a post 1978 car. Also the high idle measurements are not provided which definitely are required for a 2002 car.

In Irish test the CO idle should be less that 0.50. HC has no limit on idle but on high idle it should be less than 200ppm.

For a comparison, on my '00 car the lastest measurements were:

Idle
CO: 0.01%
HC: 10ppm

3000 rpm:
CO: 0.02%
HC: 11ppm

See the difference?

Jaysus. The high idle test just says n/a on the cert so I don't know if it was done even.

Though from what you said it seems like the emissions test for the mot isn't worth much at all! Would these point to an O2 sensor problem like renegade mechanic suggested?

Am i right in thinking this is a sort of vicious circle:

Inherent flaw causes exhaust vales to fail > exhaust and O2 sensor gets damaged by unburnt fuel and detonation

jumbone

samih wrote: »

That's well out of any acceptable tolerance for a post 1978 car. Also the high idle measurements are not provided which definitely are required for a 2002 car.

In Irish test the CO idle should be less that 0.50. HC has no limit on idle but on high idle it should be less than 200ppm.

For a comparison, on my '00 car the lastest measurements were:

Idle
CO: 0.01%
HC: 10ppm

3000 rpm:
CO: 0.02%
HC: 11ppm

See the difference?

samih wrote: »

That's well out of any acceptable tolerance for a post 1978 car. Also the high idle measurements are not provided which definitely are required for a 2002 car.

In Irish test the CO idle should be less that 0.50. HC has no limit on idle but on high idle it should be less than 200ppm.

For a comparison, on my '00 car the lastest measurements were:

Idle
CO: 0.01%
HC: 10ppm

3000 rpm:
CO: 0.02%
HC: 11ppm

See the difference?

Jaysus. The high idle test just says n/a on the cert so I don't know if it was done even.

Though from what you said it seems like the emissions test for the mot isn't worth much at all! Would these point to an O2 sensor problem like renegade mechanic suggested?

Am i right in thinking this is a sort of vicious circle:

Inherent flaw causes exhaust vales to fail > exhaust and O2 sensor gets damaged by unburnt fuel and detonation in the exhaust> valves replaced but now a damaged O2 sensor causes over fuelling which burns out valves > repeat process.

If I can get the valve seals sorted and the O2 sensor sorted, I should be cured?