ABS sensor failure

So it seems these things happen in threes! The ABS sensor light came on the dash for the second time in my ownership. This means parts of the ABS system is not working and so the system is deactivated. Typically it is an ABS sensor on one of the wheel hubs that has failed and needs replacing. While the light is on, the ABS system will not be functioning, so be aware that you are likely to lock up the wheels under heavy braking especially in wet conditions.

Replacing an ABS sensor is quite a straightforward job and can save you money on garage bills if you choose to do it yourself. All you need are some basic tools, and ideally a sturdy vice clamped to a bench or similar.

To diagnose which ABS sensor is at fault and how to replace it, I’ve written a guide here to talk you through the process.

Losing power, jerky, no acceleration

More problems with the Pug! This time the car started hesistating badly under load, and felt very much down on power. Pulling out of a junction, it felt like the exhaust was blocked as the car would barely accelerate up to road speed. It was also ‘kangarooing down the road, one minute it had a little more power, then the next it was gutless again. I nursed it to work and back and set about taking a look at he possible causes. I started with inspecting the coil pack. Typically symptoms like this are down to fuelling or ignition problems. The coil pack can be a possible failure point when experiencing a misfire and relatively cheap to replace. I observed a large crack in the coilpack, with could be causing the lack of spark on one cylinder and hence absence of power. Since I had a spare coil pack I set about replacing it which was fine until I realised that Peugeot obviously have two types of coilpack. They look almost identical with the same product numbers but the loom plug is slightly different. Fail. So I managed to get hold of the correct coil pack, started the engine and… …same problem.

I booked the car into the garage to get sorted quickly and the diagnostics indicated a faulty injector on cylinder 1 and a intermittent fault on number two injector. Two replacements and the car was up and running. The garage cleaned the throttle body and inlet manifold while they were replacing the injectors.

If you’re car has the same symptoms (misfiring, down on power) you can usually narrow it down to one of the following areas (in ascending cost order):

  • Spark plugs
  • Fuel filter – blocked or dirty
  • Coil pack – cracked or faulty
  • Blocked exhaust – cat internals may have dislodged and blocked the exhaust
  • Injectors – dirty or faulty – ultrasonic cleaning can sometimes fix this
  • Lambda sensor – faulty sensor affects engine fuelling
  • Fuel pump – failed or unable to provide adequate fuel pressure
  • Camshaft timing out – backfiring
  • ECU fault

If you don’t have access to a diagnostic machine you could investigate the fault in the above order, however diagnostic checks can be worthwhile (as in my case) and tell you exactly what the problem is, for not much cash.

Another costly month! Though nice of the garage to fit an auxiliary belt, tensioner and spark plugs for free. It can pay to go to a decent reputable garage.

Clutch failure

Not a good week! Driving back from the gym one night this week, the clutch pedal felt like it’s bite was lower than normal. Then suddenly I was unable to select gears – it was as if the clutch was not disconnecting drive from the engine. So I had to carefully slide the gears in using the right amount of revs just to get me home. As I pulled up on the driveway, I tried to move the car out of second gear. Eventually it shifted and the clutch pedal hit the floor. The clutch was making an awful grinding noise in neutral which made me think this was not going to be cheap! So not having the time or inclination to diagnose a clutch fault I rang the garage and asked them to recover the next day.

The garage confirmed the release bearing was completely shot and had started grinding through the clutch forks. The annoying thing is, that I replaced the clutch with a Valeo item not 10,000 miles ago and it looks like the part was faulty as the release bearing is worn to pieces. The garage replaced the input shaft seal on the gearbox while it was off, as well as a driveshaft seal to cure a small oil leak and the Pug was back on the road for a not inconsiderable sum.

Blowing exhaust

ExhaustWith this year’s MOT drawing near I knew it was time to get the exhaust replaced. It was worn and rusty and I remember patching it up for the last MOT so it was overdue a replacement. Normally I’d choose a decent stainless steel replacement to free up a little power and stave off rust permanently, but I wanted to keep the car standard so didn’t look into performance exhaust options. I left the car with the local Wilco Motosave who put a new exhaust on from the catalytic convertor back for the reasonable sum of £150. These guys are reliable, friendly and cheap and had already patched it up for free a couple of weeks earlier. So thats another job that should help the car sail through the dreaded MOT next week.

Transmission fluid leak

Driveshaft sealI noticed a small patch of gearbox oil on the drive the other day. You’ll know if it gearbox oil by the horrendous smell!  It looks like the offside driveshaft seal is leaking. This is a circular seal that sits in the end of gearbox differential casing. The driveshaft goes through this seal. It’s possible I disturbed the seal when refitting the gearbox and driveshafts after changing the clutch. I despise dealing with transmission oil at the best of times, so I’m going to book it into the garage to sort this one out easily on the ramps.

For those of the DIY persuasion I’ve described the process of fixing it yourself .

MOT passed!

I put the 106 in for another MOT at a council MOT test centre conveniently located next to the office. Unfortunately it failed again. This time it failed on:

  • Rear brake efficiency
  • Ball joints too much play
  • Emissions over on CO.

The play in the ball joints was only evident on an MOT rig that shook the car, the tester said a crowbar wasn’t enough to budge them. I asked if he could test it with a crowbar then!
The emissions  issue was solved by swapping the Cat over which I had luckily bought months ago as a spare in the garage.
The rear brakes were doing about 25% of the effort they should have been, this turned out to be the rear brake compensator. This device alters how hard the rear brakes work  depending on the load of the car. E.g. if you fully load the boot with 70kg of kit, the compensator will ensure the rear brakes work harder. Unfortunately these often seize and regularly fail the MOT on older cars.

I decided to take it into the garage since the rear brake efficiency was definitely going to be the rear brake compensator not working as designed, and as it is tucked up behind the rear beam, it’s not a easy job when you don’t have a hydraulic ramp. Also, if the compensator needs removing and you round off one of the brake pipes, its a real pain to sort out.
I can recommend JP Auto Technics, in Swallownest as a fast, efficient garage. Theses boys have seen all sorts of motors from everyday cars to fire breathing high spec Rally cars. They sorted out the jobs in no time and got it MOT’d with no hassle.

Changing the Lambda sensor

If you’re experiencing poor fuel economy in your 106 GTi, one of the primary culprits is the Lambda (or Oxygen) sensor malfunctioning. The Lambda sensor reads how much oxygen remains in the exhaust after the combustion process. This tells the ECU whether to inject more or less fuel into the cylinders. If the sensor is not working correctly, the ECU often injects too much fuel, harming the fuel economy and not doing much good to the Catalytic Convertor. To find out if your 106 could be suffering poor economy, use the Around 35mpg is usually the average returned by a GTi.

Replacing the Lambda is a bit of an awkward job as it is located behind the cast iron exhaust manifold which does not make it easy to get a spanner on the sensor. The oil filter also hinders the process. To solve this problem I bought a lambda sensor spanner, designed to hinge and make getting a grip on the sensor easier.

First remove the plug on top of the gearbox. To get to the loom plug, you have to remove the Airbox. This comes out easily enough, just disconnect the hose from the throttle body and cold air feed and lift the box out. This should expose the lambda sensor plug on top of the gearbox with a red tab. Pull the red tab out and remove the plug from the loom.. Now get the car up in the air and secured on Axle stands. Get underneath the front end, and you will see above the oil filter and behind the manifold the lambda is visible. Try placing the spanner on the plug. Hopefully after some trying (and swearing) you will get a grip on the lambda and you can undo it with some force. Withdraw the sensor and pull through the wire. You may find you have to remove the oil filter to gain enough access. In this instance you may as well carry out an oil change (see ) as you will lose a lot of oil from the filter anyway.

I removed the filter, and even then there wasn’t enough room to get a spanner on the lambda. So I ended up unbolting the lower part of the manifold and dropping it down. This gave enough room to manouver the spanner and remove the sensor.
The replacement sensor I bought was part number 238 038 717 available from any good Bosch dealer and some stockists on ebay. The Peugeot part number for reference is 1429 N2

In true Haynes style, fitting the new part is the reverse of removal but take car not to touch the end of the sensor as it is very delicate.

ABS sensor failure

ABS lightSince the ABS light was on the dash (an MOT failure) I set about trying to solve the issue. First up was the issue of trying to figure out which sensor was at fault. Usually a garage will use the diagnostic machine to find out which sensor is providing faulty or no reading. Obviously I don’t have the diagnostic machine on hand, but there is another (cheaper) way…
I signed up on to become a full forum member for £5. This allows you to view the diy guides, one of which is diagnosing an ABS sensor failure. For full members the article is here. Using the guide I determined that the N/S/R sensor was at fault.

I logged onto the Eurocarparts website and ordered the correct ABS sensor for the car. Lo and behold it arrived, and turned out to be the wrong ABS sensor. So I sent it back and browsed ebay for the correct sensor. Having ordered the sensor, a nice Glaswegian guy called to check my registration and make sure it was the correct one. The sensor arrived and was thankfully the right one.

To change the sensor first get under the rear of the car and trace the ABS sensor back under the rear beam to the blue plastic plug. Remove this and work your way back to the hub, removing the
cable clips as you go. To get the old ABS sensor out requires patience and brute force!
Remove the rear disc protector by removing the 3 torx screws in the back of the hub. Next its helpful if you remove the brake pad carrier and brake disc. This allows you full access to the ABS Sensor. A set of Mole grips are very useful for grabbing the sensor and removing it. If it’s never been changed, you’ll need patience as it will almost certainly be near-seized in the hub. You will destroy the sensor on removing it, I managed to pull the electronics out of it metal casing! To removed the casing from the hub I had to hammer it with a screwdriver until finally, it came out. Clean the hole in the hub and gently work the ABS sensor in until it is in place. Once the ABS sensor is connected up, it will take time for the ABS ECU to recognise the sensor is now working and turn off the ABS sensor light on the dash, so take the car for a run for a few miles and job done.

Locking wheel nut woes…

Wheel nut and keyThe standard Peugeot locking wheel nut keys are often poorly made and subject to snapping easily. This happened to me recently, leaving me to remove the wheel nuts with no key. If you find yourself in this situation like I did, theres an easy solution. Take a 19mm socket and hammer it onto the wheel nut until its securely fixed onto the nut. Take a ratchet and simply undo the nut! So much for secure locking nuts! I recommend once you get the nuts out, you replace them with more secure ones like a set from McGard. These are much more effective and harder to remove, but the keys are made of much stronger stuff and won’t break. And if you lose the key you can order replacement keys easily via email or phone.

McGard locking nuts for sale:

Fitting a GTi Wheel Arch Extension

Wheel arch fittingFor the last couple of  months, I’ve been running around with a missing offside wheel arch extension. These form part of the standard bodykit fitted to all GTi models as well as some of the other models in the range. Since I managed to rip one of mine off trying to reverse out of a very narrow and extremely steep concrete driveway, I needed to set about fixing it. So I got hold of a sprayed wheel arch extension and fixings ready to fit.

To change it, start by jacking up the car, securing with an axle stand and taking off the wheel. Once you have the wheel removed you’ll need to remove the inner plastic wheel arch. Do this by pulling on the arch, removing the thumb clips as you go round. Eventually when youve pulled it out youll be able to see the holes in the wing for the arch extension. Use this opportunity to remove any debris and mud that may be hidden behind the wheel arch to prevent any rust problems in the future.

Now offer up the arch and press into the bodywork.

Remove the arch liner to get to the clipsYou’ll need the fixings from Peugeot that hold the arch extension to the wing. I reused 4 of the rubber parts from the old clips.  I found using a socket to help press the fixings on while pushing with your hand from the outside helped. After you fix all of the clips, check to make sure they’re all secure and there’s no gaps in the bodywork. Refit the wheel, remove the stand and jack.

Torque the wheel nuts up and voila!

Brake light fix

Brake light issuesThe 106 has had a rear brake light out for a while now. I’d checked the rear bulbs, circuit board and wiring were all ok so I took a chance on and bought a brake pedal switch from Peugeot in the hope that it was the switch at fault.

The part number for the switch is 4534.52

Now although it’s awkward to position yourself to see/feel the brake switch, it is very easy to change. I managed to spend about 3 minutes looking for the switch and 2 minutes changing it over!

Youll need to open the drivers door and lean down head first into the footwell. Position yourself to look up to the top of the brake pedal. You might have to pull a little bit of carpet out of the way. Push the brake pedal down with your hand and you will see the switch at the top of the pedal’s travel. To remove the old switch, unclip the loom from the top of it. Now grab the top of the switch and wiggle it back and forward until the ribbing on the bottom half of the switch slides out and you can withdraw it.

Push in the new switch, reconnect the loom and test your brake lights. Hopefully you’ll just have solved the problem for a few pounds and 5 minutes of your time!

Brake light problem

My brother noticed at the Angelesey trackday that the offside brake light wasn’t working. Fine I thought, a two minute job to swap out the bulb. Oh no, not on a Peugeot. Turns out the bulb is completely fine, but for some reason the circuit is not working when the brake pedal is pushed.

So I whipped the multimeter out and I successfully tested 12V for the rear lights, but nothing on the circuit board when the brake pedal was pushed. I removed the plug for the light and tested for 12V. Again, nothing.

I am down to 2 possible culprits at the moment. A broken wire in the loom and a faulty brake switch on the pedal. The brake switch is quite cheap so that is my first area of investigation.

Another French electric problem, that rapidly becomes a pain in the rear!


Another day another noise! Seems like owning a Peugeot is a constant battle keeping it knock and noise free. This time the noise was clearly eminating from the exhaust causing a loud rattling sound.

I narrowed it down to the Catalytic Convertor rattling, as shaking it produced the noise. I convinced myself that the cat had collapsed due to the exhaust temperatures and abuse it got at the last trackday and that the internals were probably shot. So armed with a second hand OEM Cat (£20, bargain!) I got the car up on stands, removed the cat and had a look inside.

Rattling around in there was short length of tubing. The impressions on the end suggest it was attached at some point, though where, I’m not exactly sure.

Since the cat looks non OE, I have a hunch it was a used as a bit of a bodge job by a garage to seal the exhaust up.

I removed the part, replaced the cat and carefully clamped up the join with a generous helping of exhaust paste. Running the engine for 10 minutes helped ‘cure’ the join and a test drive beckoned.

The beautiful sound of silence. Another problem solved for pennies. 🙂

Driveshaft woes

The culpritAn annoying noise started to plague me not long after the last trackday at Brands Hatch. The symptoms were a whining, grinding type noise that increased with wheel speed. Dipping the clutch/putting into Neutral when moving caused the noise to appear instantly. This seems to point to a driveshaft or brake problem. The offside brake disc was getting hot on the back which pointed to a binding brake caliper.

A visual inspection revealed a damaged rubber caliper boot but nothing that won’t last until I sort larger calipers in a month or two.. I decided to take off the caliper and give the brakes a good clean.

Happily, this solved the binding but the noise was still present. It was difficult to locate when listening under the car, but it seemed liked the driveshaft was the next logical culprit.

Having placed the order from Peugeot for a new offside driveshaft, not only was my wallet was considerably lighter but I was told there was a 2 week lead time! Luckily the part arrived next day, and I could set about fitting it.

Sub-zero temperatures didn’t make it an enjoyable task but the swap was straightforward apart from the wishbone balljoint needed a lot of persuasion to come out. I refilled the gearbox with transmission oil, and took it for a test drive.

Noise gone! Result.

An inspection of the old shaft showed little of interest, other than a jubille clip had been used on the outer joint instead of the correct clip, which can’t have helped. I hadn’t seen a worn driveshaft display symptoms like this before, as they either usually shake the gearstick or cause the steering to pull if the CV joint is badly damaged and lost its grease. Of course, trackdays put extra stress on suspension and drivetrain components so work like this is not unexpected.

Peugeot employ a exchange policy on driveshafts so the old shaft is now winging its way back to them for some TLC to see use on another 106 one day 🙂