Frankp52
Guest
Hello everyone.
I am new to posting on this forum. I have used it for help in the past and feel it's time to hopefully help someone else out. Just to be clear though, I am NOT an mechanic by any means, but I'm willing to try some fixes to save myself some money, and find out a bit about my car in the process.
I have a bog standard Leon 1.4S 53 plate. Over the last few months the engine developed a pretty scary habit of simply cutting out completely without any warning. This is not good when you're overtaking on a motorway and there's other fast cars behind you! The engine would generally 'jump start' back again almost immediately, but as I said - not good. Oh, and the engine management warning light would come on too, and then usually go off again after a day or so.
Anyway, diagnostics turned up an intermittent speed sensor fault. So I had a look around, checked out the price of a sensor, what they looked like and thought - 'yeah I can replace that it's only held on by one bolt, can't be that hard!' How wrong I was.
Firstly (according to my research) there's two speed senors - the camshaft sensor and the crankshaft (or crank angle) sensor. After reading loads on the forums I opted to replace the Crank Angle sensor because I suspect that's what's causing the problem.
First thing to do is buy it. It's part number 41944030 Crank Angle Sensor from Euro Car Parts. I bought the Bosch one which cost £63.30. There's also one for about £35, but I heard some rumours about problems with non-OE parts so decided to play it safe.
Next find the old one and remove it. Now this is where I had a problem, no one online has definitively specified where the sensor is, these sensors seem to be in umpteen different places on different engines. Hopefully this will help you find yours.
I have photos, but I'm not allowed to post them due to me being a Newbie. (I've loaded the pics on to Flickr and Keithslippery has kindly posted the URL for me. See further down this thread).
On my 1.4S the sensor in unbelievably located in the single most awkward position possible on the back of the engine block. There is NO EASY WAY to get to it. I had the car up on ramps, I climbed on to the engine, I jacked the car higher than the ramps and put it on stands, but no matter what I did, I COULD NOT SEE IT. So I found it by following some cables and had to work blind.
So with the car raised up and me crawling around under it, I finally found the cable running down the back of the engine. Its the cable that runs alongside the Knock Sensor cable (see photos). My hand then found the rubber bung which covers the hole that houses the sensor, so I removed it. Next came the painful experience of trying to locate the Hex bolt in the hole in the engine block that houses the sensor (the photo will help with this a lot).
With the hex bolt located your next, virtually impossible, task is to attach an allan key to it (I think it’s 4mm - I checked it against my replacement sensor to make sure it fitted).
Getting the allan key on to the bolt took me about 25 minutes because I couldn’t see the hex bolt and had to try to feel my way around with the allan key in hand and get it on to the bolt at the correct angle - incredibly uncomfortable and difficult.
There’s absolutely no room to work, your arms are squeezed through spaces around the exhaust, the axle and the drive shafts, and there’s a big plastic housing directly above the hole for the sensor, so you can’t get your hand in above it! Yet somehow you have to get the allan key on to that bolt. Be warned, the allan key is the only thing that fits in the gap and it has to be the correct length. Too short, it won't reach the bolt, too long, you can't get it in because the angle is restricted. I tried sockets with keys in them in order to extend the arm out into some space for a bit of leverage, that didn’t work - there are too many other things in the way. I tried flexible sockets, but they wouldn’t work either. In the end the only thing I could get on to the bolt was an allan key.
Once I finally got the allan key attached, I then managed to slip a small socket and short extension on to the end of the key and this gave me the necessary leverage to free up the bolt, which needed a fair bit of force and released with a snap. I then had to remove the socket and extension and very gently try to turn the allan key with one hand (two fingers) taking great care to avoid knocking the key out. I had only about a millimetre to spare each side of the end of the key, (at least that's what it feels like) and I had no idea when the bolt was fully released because I couldn’t see!
Eventually the bolt moved in a way that felt free. So now I had to get the sensor out. It was pretty tight, but I managed to squeeze some long nosed pliers into the gap and grab the bolt, this was enough to release the sensor. It comes out of a small hole inside the big hole!
OK time to put the new sensor in. Working blind I managed to get the sensor into the big hole. Then after a lot of painful movements, crushed and twisted hands, cursing, swearing etc. I finally located the sensor in the smaller hole. I only knew this because it didn’t move around any more when I tried to move it - I was really guessing and hoping. So next, I had to get the allan key on to the bolt. About half an hour later I finally managed to locate the key on the bolt and began tightening - one hand again, gently turning the key with two fingers. I didn’t know if the bolt was actually going in but then it tightened up. You have no idea how good that felt! But I still needed to try to ensure it was properly tight, so I put the socket and the extension back on to the end of the key and tightened as much as I could. I then put the rubber bung back in place.
I had left the original sensor in place because I wanted to follow the original route of the cable with my new one. I did that only to find that the plug was also in a fairly awkward place. It’s under some plastic bits (I don’t know what they are) just to the side of the coolant bottle near the top of the engine.
Access to the plug is initially easiest from below the car. The plug is held in place on a bracket, but it can be pushed up from below to release it from the bracket and then it’s an easy job to unplug the original sensor, plug in the new one and simply pop the plug back into the bracket.
That’s it really. It should’ve been a simple job. One hex bolt and one plug, but oh no, it took me hours and was probably the worst job I’ve ever had to endure when working on a car.
Tools you will need - 1 allan key, something (like a socket and extension) to attach to the allan key to give you some leverage, 1 pair of long nosed pliers to remove the sensor, 1 small screwdriver to release the clip on the plug.
Hopefully this will speed things up for you, or at least prepare you for the hell that is Crankshaft Sensor replacement on a Seat Leon 1.4.
If someone can tell me how to add the photos I'll put them up. It asks for a URL to link to pics, but I don't have a URL for them, they're stored on my laptop. Is there a simple way to upload them?
I am new to posting on this forum. I have used it for help in the past and feel it's time to hopefully help someone else out. Just to be clear though, I am NOT an mechanic by any means, but I'm willing to try some fixes to save myself some money, and find out a bit about my car in the process.
I have a bog standard Leon 1.4S 53 plate. Over the last few months the engine developed a pretty scary habit of simply cutting out completely without any warning. This is not good when you're overtaking on a motorway and there's other fast cars behind you! The engine would generally 'jump start' back again almost immediately, but as I said - not good. Oh, and the engine management warning light would come on too, and then usually go off again after a day or so.
Anyway, diagnostics turned up an intermittent speed sensor fault. So I had a look around, checked out the price of a sensor, what they looked like and thought - 'yeah I can replace that it's only held on by one bolt, can't be that hard!' How wrong I was.
Firstly (according to my research) there's two speed senors - the camshaft sensor and the crankshaft (or crank angle) sensor. After reading loads on the forums I opted to replace the Crank Angle sensor because I suspect that's what's causing the problem.
First thing to do is buy it. It's part number 41944030 Crank Angle Sensor from Euro Car Parts. I bought the Bosch one which cost £63.30. There's also one for about £35, but I heard some rumours about problems with non-OE parts so decided to play it safe.
Next find the old one and remove it. Now this is where I had a problem, no one online has definitively specified where the sensor is, these sensors seem to be in umpteen different places on different engines. Hopefully this will help you find yours.
I have photos, but I'm not allowed to post them due to me being a Newbie. (I've loaded the pics on to Flickr and Keithslippery has kindly posted the URL for me. See further down this thread).
On my 1.4S the sensor in unbelievably located in the single most awkward position possible on the back of the engine block. There is NO EASY WAY to get to it. I had the car up on ramps, I climbed on to the engine, I jacked the car higher than the ramps and put it on stands, but no matter what I did, I COULD NOT SEE IT. So I found it by following some cables and had to work blind.
So with the car raised up and me crawling around under it, I finally found the cable running down the back of the engine. Its the cable that runs alongside the Knock Sensor cable (see photos). My hand then found the rubber bung which covers the hole that houses the sensor, so I removed it. Next came the painful experience of trying to locate the Hex bolt in the hole in the engine block that houses the sensor (the photo will help with this a lot).
With the hex bolt located your next, virtually impossible, task is to attach an allan key to it (I think it’s 4mm - I checked it against my replacement sensor to make sure it fitted).
Getting the allan key on to the bolt took me about 25 minutes because I couldn’t see the hex bolt and had to try to feel my way around with the allan key in hand and get it on to the bolt at the correct angle - incredibly uncomfortable and difficult.
There’s absolutely no room to work, your arms are squeezed through spaces around the exhaust, the axle and the drive shafts, and there’s a big plastic housing directly above the hole for the sensor, so you can’t get your hand in above it! Yet somehow you have to get the allan key on to that bolt. Be warned, the allan key is the only thing that fits in the gap and it has to be the correct length. Too short, it won't reach the bolt, too long, you can't get it in because the angle is restricted. I tried sockets with keys in them in order to extend the arm out into some space for a bit of leverage, that didn’t work - there are too many other things in the way. I tried flexible sockets, but they wouldn’t work either. In the end the only thing I could get on to the bolt was an allan key.
Once I finally got the allan key attached, I then managed to slip a small socket and short extension on to the end of the key and this gave me the necessary leverage to free up the bolt, which needed a fair bit of force and released with a snap. I then had to remove the socket and extension and very gently try to turn the allan key with one hand (two fingers) taking great care to avoid knocking the key out. I had only about a millimetre to spare each side of the end of the key, (at least that's what it feels like) and I had no idea when the bolt was fully released because I couldn’t see!
Eventually the bolt moved in a way that felt free. So now I had to get the sensor out. It was pretty tight, but I managed to squeeze some long nosed pliers into the gap and grab the bolt, this was enough to release the sensor. It comes out of a small hole inside the big hole!
OK time to put the new sensor in. Working blind I managed to get the sensor into the big hole. Then after a lot of painful movements, crushed and twisted hands, cursing, swearing etc. I finally located the sensor in the smaller hole. I only knew this because it didn’t move around any more when I tried to move it - I was really guessing and hoping. So next, I had to get the allan key on to the bolt. About half an hour later I finally managed to locate the key on the bolt and began tightening - one hand again, gently turning the key with two fingers. I didn’t know if the bolt was actually going in but then it tightened up. You have no idea how good that felt! But I still needed to try to ensure it was properly tight, so I put the socket and the extension back on to the end of the key and tightened as much as I could. I then put the rubber bung back in place.
I had left the original sensor in place because I wanted to follow the original route of the cable with my new one. I did that only to find that the plug was also in a fairly awkward place. It’s under some plastic bits (I don’t know what they are) just to the side of the coolant bottle near the top of the engine.
Access to the plug is initially easiest from below the car. The plug is held in place on a bracket, but it can be pushed up from below to release it from the bracket and then it’s an easy job to unplug the original sensor, plug in the new one and simply pop the plug back into the bracket.
That’s it really. It should’ve been a simple job. One hex bolt and one plug, but oh no, it took me hours and was probably the worst job I’ve ever had to endure when working on a car.
Tools you will need - 1 allan key, something (like a socket and extension) to attach to the allan key to give you some leverage, 1 pair of long nosed pliers to remove the sensor, 1 small screwdriver to release the clip on the plug.
Hopefully this will speed things up for you, or at least prepare you for the hell that is Crankshaft Sensor replacement on a Seat Leon 1.4.
If someone can tell me how to add the photos I'll put them up. It asks for a URL to link to pics, but I don't have a URL for them, they're stored on my laptop. Is there a simple way to upload them?
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