6n Common Faults

Chat about your MKIV (6N) Polo
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Joined: Sat May 16, 2009 11:19 pm

Re: 6n Common Faults

Post by smickers4 »

Looking help on my non running 96 1.9d cl.
Turning over and starting briefly then dies again??? :(
Getting There!
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Joined: Fri Aug 07, 2009 9:58 am

Re: 6n Common Faults

Post by Lowrider6n »

The problems ive had are

distributor went, left me stranded on a roundabout, you only notice its on its way out when you are driving and then your have no power, no electrics but then it all comes back.
blockage in the radiator, made the car overheat within 2 mins from cold, bit of a pain to change, front bumper, slam panel and head lights have to come out for a simple swap.

i recommend using vw approved thermostats as i bought one from dave edwards autospares and put it in, and when it was warm enough to open to let the water though, the pin off it broke making it overheat again, making me have to drop the water and replace, and when antifreeze is 6 pound a litre its a pain in the backside.


If your car rusts....go with the rat look!!! 8)
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Re: 6n Common Faults

Post by f1basgh »

I bought a 2001 VW Polo Estate 1600cc only 4 months ago F/S/H 66000 miles . Since buying New full exhaust including cat , New ECU , New Throttle Body , Cannot stop immobiliser faults being logged IE Engine Section , No Start due to Immobiliser , Immobiliser Section , Key Low Signal . Put on New Pick up Coil , New Immobiliser , Keys ECU and Immobiliser coded . To be honest bought it thinking of VW supposed reliability how wrong can you be !!!!!!
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Re: 6n Common Faults

Post by SlimDubs »

I've owned my N reg mk4 1.4cl for around 2 months, it's done 92000 miles.
There seems to be a problem when I'm slowing down and changing down gears.
When I put the clutch in the revs completely drop and my engine cuts out leaving me with my dash lights on and me rolling around corners or putting it into a lower gear and bump starting it or turning my key and starting it again.

Any ideas why this is happening guys?
The bloke that a bought it from had a new distributor fitted recently as there are receipts for this, and new battery by the looks of things.
No one seems to be able to tell me what's causing this...
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Re: 6n Common Faults

Post by racerjonzo »

throttle body mate, common problem, mine done this wen i bought it, its a pain... though mine still does it very rarely now but spray and clean your throttle body with degreaser or WD40 it helps alot
if you post in the main section instead of this thread, youll get more answers... just click start a new topic ;)
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Re: 6n Common Faults

Post by SlimDubs »

Cheers mate!
I'll give that a go ;)
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Re: 6n Common Faults

Post by twincampolo »

water ingress!
window slot seals, door membranes, cabin filters, scuttle panels.
everything can leak slowly so you don't notice until you have every problem, then you have to fix them all at once.
pour some water on the windscreen and windows and check to see if ESPECIALLY the nearside rear footwell is wet.
gotta love 6n's :)
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Joined: Wed Aug 04, 2010 4:09 am

Re: 6n Common Faults

Post by tomofathos »

Recently bought a '97 MK4. Brilliant car but as with any car of that age, it had a few problems. First thing was the fins inside the water pump had smashed. She then started overheating. Changed the thermostat, flushed the radiator, that fixed the problem for a few days. Im now thinking that its the thermostatic switch in the radiator. As far as rust goes, underneath is fairly solid, cant find any sign of 'chicken mess' welding, although the back arches are starting to go, the bottom corner of the driver door is going too. Also steering is quite heavy, although it doesn't have power steering, its allot heavier than other cars without it.
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Re: 6n Common Faults

Post by willson1992 »

i've had my 1995. 6n for about 2 months now.
So far i've had;
-Wheel bearing
-Leaky sunroof
-Bracket inside pedal box snap
-new clutch
-brake light switch fecked.
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Joined: Wed Feb 23, 2011 4:15 am

Re: 6n Common Faults

Post by koolie »

Heres my experience, apologies if its slightly long and comprehensive in detail...

I've got a 1999 1.4 8v CL with MOTRONIC MP 9.0 ECU - Type 6N1

if it was a GTI it would more than likely be a 6N2 with Marelli ECU if I am not mistaken?

The scan tools used by some garages (e.g. Bosch KTS 200 used by Kwik Fit) .... with dual meanings or vague descriptions, making you look in the more expensive direction instead of the simple things that may cause components to fail (so sometimes deeper the diagnosis, the better)

VAG codes are generally more conclusive than OBD codes, personally speaking from experience... because the VAG group wanted to be special, we all know they are :D

-------------------Problems I've had------------

Started with a misfire on cylinder 4, causing catalytic converter to overheat and fuel consumption to sky-rocket

got OBD codes of P0215 --- idle control above adaption limit (could also mean... FUEL INJECTION PUMP CONTROL CIRCUIT)
and P0231 --- Lambda adaption additive too low

got a VAG code for them 00533 - Idle Speed Regulation Adaptation Limit Exceeded (additive too low)

Something the codes had in common was a faulty fuel pump relay.... turns out not so, so far! how confusing!


Replaced the sparks then distributor cap and HT leads, cured the misfire... for now at least...

Cured the fuel consumption, CALMED the erratic idle and stopped the stalling during braking/gear changing, for now... by:

Adding some Redex carb cleaner... I think this should be a mandatory part of the driving test... particularly with Polo owners... erratic idles/fuel consumption/stalling appears to be a common one!

reseated the air filter on the throttle body and the tube - so far, no more P0231 codes or 'additive too low' errors.


The catalytic converter needs replacing now anyway....

still getting the P0215 on the bosch - this could just be a throttle body adaption calibration as the battery was replaced by monkeys? which the bosch KTS 200 cant do!!!

I'd like to inspect the Idle Air Control Unit first and the throttle body re-calibration before going for the whole throttle body replacement...

Note:the following requires a certain level of common sense/self-restraint, problem solving and may require the process of elimination in some instances and support from people in the know-how... and generally a model made AFTER march '99, when they implemented the crypto for their ECU's

The Autel Maxiscan VAG405 (around £50) appears useful for VW initial diagnosis - shows VAG and OBD codes, but relys upon the accuracy of the sensors but is UNABLE to do basic settings or adaptations, e.g. Throttle body adaptation!

For such tool, maybe a Memoscan VAG5053 (around £80) would be best suited, to someone who knows what they are doing with basic settings and adaptations...

The true geeks tool for geeks - VAGcom(now VCDS) is more useful for seeing the absolute raw output of sensors, may perform more functions, and will warn you better (£200+)

I have discovered that vehicles with the Bosch Motronic MP 9 ECU, may suffer from the 00530 or 00533 VAG code bug, which "may" also translate to P0215 in OBD codes

Basicly, whenever that has a problem, Get VCDS first to diagnose, and only if you know what you are doing, as a last resort, run 'ResetMP9' from:

So basicly the ECU can give you the run around

Hope this helps some... again apologies for it being long and in depth! I take no responsibility for anyones actions resulting from reading my post...
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Location: manchester

Re: 6n Common Faults

Post by faulky »

i have had up to now

bent cams ( all new top end )
wheel barings twice
warped discs
all new interia ( it was cream didnt stay cream for long)
now need new mirrors 1 wont move and the other dosent heat up
painted (rust has come back)

but that idle is the 1 that does my head in keeps cuting out in traffic
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