Author Topic: BUYING GUIDE / COMMON FAULTS  (Read 50656 times)

Offline Rhyso

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BUYING GUIDE / COMMON FAULTS
« on: 19 April 2006, 15:46 »
My headlight / sidelight bulb has blown. How do I replace it?
Opinions differ on this one but I found it was easier to remove the bumper and the headlight unit to replace the bulbs. Others have done it in situ but it can be quite fiddly. This link will help with bumper removal.
Link to: Bulb replacement

My car has flat spots when accelerating.
Possible causes are a faulty or dirty MAF sensor, split turbo hose, faulty EGR or N75 boost control valves. These don’t always appear as faults on VAGCOM. MAF sensor appears to be the most common fault. Cleaning the MAF may help but ultimately, it needs replacing.
Link to: MAF Clean and MAF Replacement

How do I remove my OEM head unit?
Cut a sturdy but no longer required credit card/plastic card into 1cm strips lengthways. Insert these into the slots located on the left and right hand lower sides of the HU and it will unlock and you can then remove it.

My W8 Interior light rattles like mad with even moderate bass.
Take light out; split top cover from base unit by releasing clips; then remove lense from cover again by releasing clips. I superglued the lense back in and wedged small lumps of blu-tack between cover and body of light. (pikey but effective) and no more pesky rattles. Also useful if you want to colour code W8 light for an Anni as you only need to spray the cover.

My rear washer isn’t working.
It’s likely that the washer hose has detached, probably from the motor. Sometimes it can detach in the pillar / roof lining but you’ll probably notice a wet patch.
Link to: Washer repair (tailgate) or Pillar

My car keeps stalling / misfiring.
This could be caused by a faulty MAF sensor (again), temperature sender, relay 109 (diesels only), dirty throttle body, faulty coilpacks (petrol) or dirty contacts on the ignition amplifier (AGU 1.8T Engine Only). Relay 109 - the sure-fire sign is when you try to start the car, the glowplug lamp stays out. After a few tries, glowplug light comes on, car starts.

My window has fallen into the door.
The plastic window regulator has probably failed. Repair kits are available, which contain metal clips.
Link to: Imagewerx Regulator Guide - Vortex Window regulator repair guide

My central locking / door lock / alarm isn’t working.
This could be due to a faulty door lock module. You might be able to repair the faulty door lock by re-soldering the connections. Some people seem to have success simply spraying with WD40. Otherwise, it's a case of having to replace it.
Link to: Door lock module info and repair

My windscreen wipers have stopped working.
The mechanism has probably seized. You can either replace the mechanism or strip it down, rub it with wet and dry and re-grease.
Link to: Wiper guide

There's a rattle when I accelerate.
This usually means the front or centre exhaust mount has snapped,small amount of welding needed or you could try using some large jubilee clips.

My cooling fans don't seem to be working correctly when the aircon is running.
Unfortunately, this is another common fault on the MkIV. I THINK it mostly affects the models that have climatronic aircon. To check if your fans are faulty, Andymac recommends the following:
1. turn engine on,
2. turn aircon on,
3. make sure ECON is "OFF"
4. Check fans are running constantly IE for more than 1-2 minutes
5. if the fans do nothing then run very fast, then stop after a minute or 2 or even 3 then you have faulty fans
Link to: Fan synopsis and fix

My key-fob doesn't work
Assuming that the batteries are ok, it's likely that the key has lost it's code. If you have 2 keys, put one in the ignition and turn on (I'd lower the windows, just in case!), manually lock the drivers door with the other key. Press either/both buttons on the remote (alarm should chirp). Manually unlock the door and turn the ignition off. It should now be coded.

My rear seats and boot lining are wet
First of all, check the headlining. If that's wet as well, it's probably caused by the rear washer hose connection - click here for a fix. If it's not wet, it may be the rear vent seals that have perished - click here.

There's resistance in the steering followed by a strange twanging noise, especially when making slow, full lock maneuvers.
Strut top bearings possibly seized.

Boot light doesnt work
Possibly a blown bulb but more likely the rear washer hose has popped off and soaked the boot catch. There is a microswitch in the mechanism that doesnt like getting wet. Remove the boot lid cover by undoing a screw in each handle on the inside, then pull the plastic cover to unclip. The boot catch then comes out by undoing the 2 large spline bolts. Try drying the switch with a hairdryer after stopping the leaking hose, or ultimately replace the whole boot catch. Can also cause the alarm to act strangely.

Heated mirrors don't work
First check to see if your car has them! Pop the mirror glass out by getting your fingers behind the outer edge and pulling, if there are 2 wires attached then they are heated. They are activated by turning on the rear window demister. Check to see if there is 12 Volts across the 2 wires, and/or check the fuse. If there is 12 Volts there and the glass doesn't get warm then the mirror glass needs replacing.

When I adjust the driver's wing mirror, the passenger mirror also moves but when I adjust the passenger mirror the drivers side stays still - is this a fault?
This is a feature not a fault, for convenience when adjusting for different driver height etc. To adjust mirrors, move the drivers side first (R) and then adjust passenger side (L) if necessary

The traction control light is coming on whilst I'm driving
This might also throw an alternator fault code also. The light will go out if the engine is switched off and back on. Follow the 2 small wires from alternator to a connector at front of gearbox, the wires break at that connector.

There's a clunking noise when I go over small bumps.
Possibly caused by worn Anti-Roll Bar bushes.

There's a clunking noise coming from the rear end when I go over bumps.
Rear axle bushes are probably worn and require replacement. This can be an MOT failure so best to be repaired soon after spotting.
Link to: rear axle bush discussion.

EPC light keeps on coming on.
The epc light keeps coming on and goes when the engine is restared, this is a brake light switch failure. go to the stealers and give your chassis number over.. there are over 5 types and several revised version so the chassis number is needed.

INDICATORS sticking of flashing at random intervals
the indicators stick or dont flash with an equal time between them, the light relay has gone this is integrated into the hazard switch.. again a chassis number is needed
« Last Edit: 24 June 2010, 21:09 by Rhyso »

Offline Rhyso

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Re: BUYING GUIDE / COMMON FAULTS
« Reply #1 on: 19 April 2006, 20:50 »
General things to check:

Make sure the car has been serviced according to the handbook (yes i know its an obvious point  :tongue:)
this inlcudes
cambelt - this does seem to vary from model to model but the general rule is it should be changed at 60K and if you got a 1.8T lump see if the water pump has been done as they are another common fault; not sure if it applies to other models......
oil has been changed
brake fluid changed every 20K etc

another obvious point - TAKE IT FOR A TEST DRIVE - ensure the car is started from COLD as this will help to identify any potential starting / ignition / running problems.  when on the test drive make sure the car pulls cleanly in every gear and look for flat spots in the acceleration.  flat spot  = MAF failure (usually!)

might also be worth getting the car HPI's as this will let you know if this outstanding finance or if it has been in a crash

check that all body panels are straight and that the doors haven't dropped - the hinges are a weak point due to the door being so heavy  :huh:

have the window regulator clips been replaced?? the originals are plastic and are prone to failure  :sad: repair kits are around £70 from the stealers

UPDATE - if you car is under 6 years old and the clips fail VW will pay the FULL COST to replace them.  It used to be 50% but after checking they confirm that they now pay the full cost! 

so get breaking people and get them repaired for free before its too late!!

PS - apologies if your car is over 6 years old and you've had to foot the bill yourself 


check the air con system - cars with climatronic have had problems with the compressor failing

on the Anni editions make sure the alloys are in good nick cos they are notorious for the lacquer peeling and flaking.........
« Last Edit: 20 June 2006, 15:45 by Rhyso »

Offline GolfGL

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Re: BUYING GUIDE / COMMON FAULTS
« Reply #2 on: 26 April 2006, 23:55 »
Good link to DIY of common problems http://forums.vwvortex.com/zerothread?id=764935 from fireman sams thread.
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Offline GolfGL

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Re: BUYING GUIDE / COMMON FAULTS
« Reply #3 on: 28 April 2006, 15:40 »
A few problems i have had and sorted out quite easily;
Cigarette light stops working - most likely down to a blown fuse
Car turned off for short period then not starting and rougher idle than standard - Coolant temperature sensor replacement £20-£25(VW)
Woble when braking - Warped discs - caused by pushing brake pedal down when stopped as there is a massive amount of heat at one point on the disc it expands. Also when discs are old and thinner heat is more of a problem. And brakes arent bedded in correctly.
High emisions - might have this problem when having MOT done. Usually caused by oxygen sensor or MAF giving the Oxygen sensor abnormal readings readings.
Rear washer not working - On mine it wasnt down to the connector but actually the brass pipe that leads upto the jet had snapped as it turns (another sign of vw not thinking). Can be replaced but a bit tricky otherwise £70 from (VW)
Knocking from engine - my mate had a high mileage 1.8t and had a knocking which turned out to be a oil pump.
Noise when turning on full lock at low speed - also on my mates 1.8t high mileage again caused the strut bearing to become seized.
Hope this helps some of you
Audi TT 3.2 24v v6 2005 - The Sloth - Weekends
VW Golf 2.0 8v GTI 1996 - Lemonade II -Daily
MNR Vortx Yamaha R1 2009 - Track days
Sold Seat Leon Cupra R 225 -LM04 NDE "Lemonade"

Offline GolfGL

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Re: BUYING GUIDE / COMMON FAULTS
« Reply #4 on: 21 September 2006, 22:38 »
VW waterpumps are made of plastic and are sh@t. My car is comming up to 60k so i decided to book it in for the waterpump and cambelt. Waterpump came off and only a third of the impellor was there. Who knows how long its been broken but ive now had it replaced with a gsf metal one for only £25 inc vat so id recommend doing it.
Audi TT 3.2 24v v6 2005 - The Sloth - Weekends
VW Golf 2.0 8v GTI 1996 - Lemonade II -Daily
MNR Vortx Yamaha R1 2009 - Track days
Sold Seat Leon Cupra R 225 -LM04 NDE "Lemonade"

Offline richandhazel

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Re: BUYING GUIDE / COMMON FAULTS
« Reply #5 on: 04 October 2006, 12:28 »
Couple more things to look for when buying:-

1. It is very common for the undertray to be missing. It is removed to carry out regular servicing and quite often doesn't get put back on. With this missing you will suffer increased road noise, reduced aerodynamics and all the sh@t from the road will be thrown up into the engine bay. They aren't cheap to replace!

2. The throttle box can fail. You can carry out a quick check by holding the accelerator at somewhere between 2000 to 3000rpm and at the same time press the brake. The rpm should drop back down to idle.


Offline Ridg

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Re: BUYING GUIDE / COMMON FAULTS
« Reply #6 on: 20 July 2007, 11:26 »
Glove box

Quite common for the "latch" mechanism to fail.  whilst replacements are easy to find on eBay odds the lock wont have been changed so you'll end up with a glove you can't lock.

Offline richw911

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Re: BUYING GUIDE / COMMON FAULTS
« Reply #7 on: 11 February 2009, 21:36 »

MKIV Mod Squad™ a part of the headlight police.

Offline Wayne

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Re: BUYING GUIDE / COMMON FAULTS
« Reply #8 on: 23 May 2011, 10:15 »
Another thing to check etc.

Oil pump suction pipe, if you can see no record of it being changed then it is well worth looking at replacing around 75k, the parts are not expensive.

Offline Rhyso

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