Wobsta

So to update and mark (fingers crossed) as solved, I finally got bored of driving around with the EGR vacuum unconnected and investigated further today. For ****s and giggles, I reconnected the vacuum pipe half expecting to be back to the original state of affairs described in the first post, but no, car was exactly as without it connected. Now I know the problem can't be lack of vacuum since brakes, turbo etc still work OK, so still points to a goosed EGR valve or the controlling N18 solenoid, So I put a vacuum gauge on the EGR vacuum pipe, started it up, and gunned it from idle a few times to about 3-3.5k revs. At this stage, I can't say that I knew what I should be seeing but I what I did see was clearly wrong. The gauge sat at around 2 inches and gunning made the needle shake, but it stayed at around the same. Clearly there should be some change there as the alternative is that the solenoid does nothing (clearly not the case). To be sure, I checked the vacuum in, and sure enough I was showing around 27inches there, so all good to the inlet of the solenoid. So, whipped the solenoid off to investigate. I applied 12v to the terminals, and not a thing. Should at least fee a click or hear something, I thought, but no. The N18 I have looks like this (not mine, didn't take photos but looks the same) So, to investigate further, I took a junior hacksaw to the metal band at the tap and released it. The top part then separates from the bottom part. The top part didn't appear to be blocked at all. The bottom half has a plunger the full depth of the bottom half with a red diaphragm at the top where the two parts join (so roughly where that metal band sits). Knowing how a solenoid works, the plunger obviously should move freely. Well, it didn't. So I removed the rubber diaphragm to avoid damaging it, and using some mole grips I removed the plunger. It was very tight, and gunked in there. I cleaned the plunger with some sandpaper and the internal bore on the body with sandpaper wrapped around a screwdriver. Then flushed it with some brake cleaner, dried it, applied some light machine oil, reassembled, put the metal ring back and secured it with a zip tie. Tested it on the bench, got a click. Put it back in the car, connected the vacuum gauge to the EGR pipe, and repeated the gun to 3k from idle, and lo and behold we now have over 15inches at idle and zero with some hefty throttle. So some significant differences in comparison to the previous state of affairs. I cleared the error code, and so far so good. Previously the error would com back within a mile or two, but so far no repeat. If truth be told I'd had an EML light for some time but put it down to the MAF sensor. Clearly I got that wrong. But for the first time in a while I have no EML showing. My guess is that the initial state of affairs I described was caused by the solenoid sticking in the open "idle" position, so that all the boost was dumped out through the open EGR. All seems to be OK for now. I guess it will need changing at some point in the future, but who knows, but might run for 2-3 years yet by which time the car will likely be deceased. Thanks everyone for their help.

So, though I'll not mark as solved yet as it could still be one of two things, I have a functioning car again. Ken, it appears you were correct; I was losing boost, but not through the boost pipes, but rather through the EGR valve it would seem. I put it all back together this morning and for good measure changed out the fuel and air filters (the latter was past its best - I live up an old unmade dusty road, so should probably halve the recommended service intervals). Anyway, I didn't expect that they would, but no difference was noticed. Then I removed the vacuum pipe from the EGR valve - back to full power again. I have to investigate further though as I think it may be the solenoid rather than the valve - perhaps someone can help? Should there be vacuum at the EGR valve at idle? Fro what I've read I think that's a no. If that is the case I believe the solenoid is shot rather than the valve as without vacuum, all is well. In any case I think I'll just delete the EGR going forward, but would like to know what caused the problem. Back on the road in any case. Will update after confirming valve/solenoid options.

Ah just realised that that part on the inlet manifold includes the exhaust gas recirculation. Maybe that's what I'm seeing coming from the inlet manifold, some exhaust. It looked exhaustish.

Yeah I know, but there's not much else I can do today. I figure it's better than nothing. stuff sticks like the proverbial brown stuff and sets nice and hard so it can only improve things I think and I have a massive tin of chem metal . If nothing else the vacuum hose will actually stay in the hose clip now since it's thick enough. It's not a permanent fix. I think it;s just the vacuum to the anti shudder valve in any case.

No it wasn't. It was still intact though very weak so I've bodged it for now with some chemical metal. It isn't the turbo though, or it least I very much doubt it is. I popped the top left rubber elbow/boost pipe twixt the inlet manifold and the plastic part and also popped the cold side turbo to intercooler pipe under the car, and I can feel air blowing from the turbo when gunned, also looks nice and clean in there which isn't what I would expect if it had failed. Guess it could just seize though and look clean, but as I say there's a pronounced volume of air coming out the cold exit side and no odd sounds which is a good thing I think. Not very scientific but the best I can do under the circumstances. I did however notice with the top elbow off that I have something (smoke/steam?) coming out of the inlet manifold which seems wrong given that the correct direct is inwards. Makes me think maybe of manifold/head leaks, maybe timing, or an inlet valve not closing sufficienty? I guess any of those would explain the lack of performance. I don't get smoke out of the exhaust either with the two pipes disconnected or not that I noticed. When the performance first dropped off the cliff, there were clouds of black smoke too, but not so much now. It's still not good, but it doesn't kill the local wildlife. Any further thoughts? I'll probably have a look at the timing tomorrow, but I guess it would be a compression test if valves aren't working properly.

Can't see anything obviously adrift there, did notice this, don't know if this is of relevance. Photos aren't great but you make out that one of the pipes is damaged, and the electrical connection is almost worn through also. I've removed it just to get a better picture of what it is, but since it;s directly connected to the valve/gate on the intake (is that the throttle body?) I guess it could be. If that could be a cause, is there a way to test?

A couple of photos. I'm guessing the oily pipe connected to the air intake hose is for burning crankcase emissions and would likely be unrelated, but the round thing on the right hand side of the block (also oily) has to be a vacuum pump since it's connected to the brake servo. I presume that boost is regulated by vacuum too, so maybe worth checking the vacuum pump. A couple of days before Xmas I did have an intermittent hard pedal. Is that related perhaps? I expect the way to check for a non obvious leak would be to pressure test, which of course I can't do. To be honest I generally leave engines alone other than servicing though I'm quite happy working on the running gear. It does seem to be a lot more complicated than the last diesel I worked on. Only really having a look as the time of year means I can't really get it in to a garage yet.

Have read of a few similar cases. Having read about how the setup works though, I guess my theory regarding the turbo being OK may be flawed. I guess the ECU could be underfueling (though black smoke implies unburned fuel I think) so maybe not enough air (scratches head). Air filter sure needs changing but I did run it briefly without the air filter on and the same problem was there from memory.

As per title, starts and idles fine. No funny noises really at idle, just sounds like the tractor that it is. KI can just about move the car on a flat surface at low speed but as soon as you put the engine under load it will just die. And there will be quite a lot of smoke and it does sound a little odd - almost like listening to the engine as though it's "baffled". I think it's something that's been deteriorating for a while as I had noticed that I had to boot the car a little more than usual up the many hills that there in these parts and thought I had seen some smoke in the rear view, but initially it was that gradual that I sort of doubted myself. I've never really had problems with a turbo, but to me this doesn't make sense that it would be a dead turbo, as I would expect some performance from it in the lower rev ranges before the turbo kicks in? Any ideas?

So yeah, IR thermometer located and used, not solved, but much improved. There's a difference of maybe 20-40C between the two fronts. If i recall correctly as well, previously the binding side ran a little hotter too though that could be a false memory, galloping senility and all that. I figure though that the servo at the very least has to be at fault because being that there is no solid connection between the servo push rod and the master cylinder socket, tapping the brake pedal up should have zero effect on the master cylinder if the master cylinder was sticking. It doesn't of course rule out that the master cylinder could have a fault of its own though. So, on to the second test of cracking the master cylinder bolts a turn or two.

I doubt the tiny spring or my foot hooking would be enough to snap the plastic bit. Having read some other posts on removing the brake pedal they deem seem to concur with your "fiddly" assessment so I'm planning on leaving that well alone. Two things make me think it's not the master cylinder is that hooking the pedal or the added spring seems to improve matters and that it only affects one front disc. Of course though, if the fault is that there is no clearance between the servo push rod and the master cylinder socket and the master cylinder is slightly activated, then it would make sense that both would bind too, but having had a look at this video: which looks like the master cylinder I have, there is a spring between the first and second pistons, and presumably a spring after the second piston which we don't see (no need to remove it I guess to rebuild, but I can't see how the second piston could retract without one ). I can theoretically see how a slight imbalance between those two springs would mean that the brake fluid transfer ports could open a fraction apart from each other. In the big scheme of things this would be unlikely to make any difference provided the master cylinder is free to move back to a completely inactive position. If however the push rod is applying a the tiniest amount of pressure, then perhaps one port could remain closed. I have found some details of a similar problem here: http://www.bba-reman.com/forums/Topic113057.aspx which describes almost perfectly the issues I have. I haven't checked the rear drums on mine, but since they aren't applied anywhere near as much as the front discs are I wouldn't expect to see as noticeable a difference in any case. In this case, two similar issues are described, and servo is diagnosed as the issue. I did also come across this: http://bigcoupe.com/phpBB3/viewtopic.php?t=16351 Of course this is on a BMW, but it also reports a faulty master cylinder that causes both discs to bind, but if you have a look at points 11 & 12 the author describes a potential situation discovered by dismantling a master cylinder that could cause a one sided bind. All that said, I think it's the servo being partially activated (and by dint of that the master cylinder too) because, as an update, the spring has now been on for 50 or so miles, and by my temperature assessment using my hand, it seems to have solved the problem though as one might expect the brake pedal action is now a little less than progressive at first application though I'm getting used to it. So back to diagnosis. I'll get by IR thermometer on the front wheels shortly and see how accurate my hand assessment is. Thereafter I'll crack the two master cylinder bolts to see whether it is indeed the servo or the master cylinder. If the latter, I'll likely live with the spring arrangement or maybe bodge something better as replacing the servo on a car this old is rather pointless. It'll likely be going to the scrapyard in the sky in the next year or so in any case as new servos are prohibitively expensive, and the ball ache involved in swapping a scrapper part over in lieu of what I have seems a potential waste time due to unknowns of second hand parts, plus of course it's still a significant amount of time even if it works when application of a spring seems to do the trick. I'll report back in a few days (or weeks if I get lazy and learn to live with the spring).

Hi, For reference this concerns a Mk1 1u5 Octavia Estate, though I ask as a general query as I imagine braking systems are not that dissimilar across the marque, or indeed across all marques. I have a binding left front brake. It isn't significant, bad enough to wear the pads that side prematurely, maybe 2-3 times as fast, and decrease fuel consumption by 4-6mpg. The wheel is noticeably hotter after drivcing. Dragging would maybe be a better description rather than binding. I hadn't really noticed until my tame MOT tester pointed it out some time ago. I have been trying to track the problem down since. So far, I have fruitlessly changed caliper, flexi hose, bled that side countless times, cleaned and greased pins. Bled master cylinder etc; all the usual culprits that I can think of have been tested/changed to no avail. The master cylinder itself is newish though not OEM (4-5 years maybe - changed it after local garage goosed the original factory part), other than it's all standard. I should add the car stops as expected, the pedal is good and not spongy and I don't notice a pull to one side. I wouldn't say I'm at my wits end as changing brake pads more regularly is hardly a major inconvenience since I DIY, but I don't really want to throw more money at it without a more solid idea of the issue. So, I have been investigating over the last few days. When the brake is dragging, if I crack the bleed nipple open, a little fluid spurts out (fnarr fnarr). This suggests that there is residual pressure in the brake line, and that the issue is not mechanical. After releasing the pressure, the wheel frees. I had noticed that things improved if I hooked my foot under the brake pedal and pulled up, that things improved (tested many times after coming to a halt at junction, releasing foot brake and remaining stationary, then hooking the brake the car would move). So, on realising this I added a brake pedal return spring. This has improved things greatly and although I haven't lifted that corner to check for bind and that corner is still hotter, it is noticeably better than without the spring. Thoughts? So my mullings. This is a tandem cylinder I believe, and have read reports on other vehicles that return route for brake fluid can be marginally different for each piston in the master cylinder I wondered whether it could be a faulty master cylinder. I have had an issue before where both front discs would bind and resolve with application of hooking, but that was fixed with the current new master cylinder. It seems unlikely that a master cylinder could cause just one to bind? Having messed with the master cylinders (both old discarded and current new), the return spring in them seem quite strong, so I don't see how either of the former scenarios I describe could be the case, though at least one has in the past. Since there is no return spring as standard the brake seems reliant on the servo(is there a spring therein) pushing it back or the master cylinder spring doing the same. IN any case so far, no matter how hard I pull the brake pedal so far, it doesn't seem possible to completely prevent the bind, The servo in the bulkhead appears to be some kind of ball and socket, so there is no potential to adjust clearance. The isn't, that I remember, any means to adjust clearance between servo pushrod and master socket interface and since I don't appear to be able to completely eliminate the bind it would appear that there is at least a very minimal connection. I guess a test I could do is when dragging (after some town driving is best), I could quickly crack the bolts a few turns on the master cylinder to provide a little more clearance and see if that frees the wheel completely. If it does, it would seem to indicate a malfunctioning servo. Can anyone else think of anything to try?

Just top add another pretty much identical situation. Garage bled the system incorrectly, and the brakes were binding. Fixed with new MC. Can be read about here: http://www.briskoda.net/forums/topic/364777-adventures-with-brakes-or-why-i-hate-garages/

Talking to myself now - it is indeed 7mm on the drums.

The reardrums look to be 7mm or thereabouts which seems to be an odd choice. Haven't got as far as the fronts yet but would guess they would be the same anyhow. Ideas?

Well, where do I start? I guess at the beginning.I've been using the same garage for a number of years - never anything complicated, a couple of tires here and there, the odd downpipe/cat etc. Noticed the rear cylinders were leaking (I have an old Octavia Mk1), so purchased some more to swap over, and some new shoes while I was at it. Trouble was, it was the thick of December mad here on the edge of the peaks, it can get a bit snowy, cold miserable and wet and being the shade tree dry weather DIY mechanic that I am, I baulked at the idea of cold fingers, wet back, dirty hair etc and in the end gave them to said garage to sort. That was a mistake. I said I'd wait while they did it; I can kill a couple of hours with a book (any time with a book is not wasted time in my opinion). The first warning was that 2 hours later they told me to go home as they were struggling. I doubt this would have taken me two hours to do. It was Christmas Eve, so I toddled off home to the wood burner and inebriated family; always good for a giggle. I returned a couple of hours later, still no dice. "I can't get a pedal", says he," it must be the master cylinder". "Well there was nothing wrong with the master cylinder this morning", says I. "But it must be", a new one is £100", (or so), I don't recall exactly but it was around that. "Make it so", says I. So we wait for delivery of said part. I give up waiting and go home again. I return at the end of the day. "Ir works", says he. "Is the new cylinder fitted?" "No, they sent the wrong one, I've given the old one a good clean" Now I know that this particular master cylinder is considered a consumable by Skoda, and I'm also aware that there are also aftermarket seal kits available. The seal kits though are not an emergency option in the locality, it's at least a next day wait. Given that neither David Tennant, Mat Smith nor Tom Baker (showing my age) are available, this must of course mean that they've reused the original seals. I guess I should have kicked off then, but it being Christmas Eve and various trips due to various corners of the country in the next few days, I didn't argue. First thing that didn't seem right - no servo assistance. That did sort itself the next morning without intervention and has never failed since. The next thing I noticed was that the brakes were binding a little; it could be resolved by hooking a foot under the pedal. That never resolved and wasn't really more than an annoyance until it failed an MOT on that and a few other annoying things at the same garage at the same garage a few days ago. Interestingly there is a related thread on Briskoda: http://www.briskoda.net/forums/topic/161705-sorry-brakes-again-solved/ .which seems to follow a similar pattern, ie problems bleeding, damaged cylinder. Anyway, failed on inoperative squirters (my bad - add water), knackered wiper blades (fair comment), number plate bulb (everything rusted so came at it through the plastic trim on the tailgate and put in LED ones so the likelihood of breakage in the short term was minimal - 4 leds per bulb, doubt they'll die before the car). And, now it rears its head: front brakes binding, rear off side hand brake inoperative. Given the previous situation, I decide to investigate. Drum off, there is no hold back spring on the leading shoe. I don't see how that could turn to dust, or not make a horrible noise by failing in the drum, they're pretty substantial but although I don't believe it was ever there, I can give the benefit of the doubt or make allowances for mistakes. Told the garage, they were surprised, but didn't quibble too much. Correcting this seemed to help a little with the binding as well, maybe the additional return spring assistance from the now functional rear brake helped a little. I'm surprised the service brake worked since it was at such a funny angle due to lack of hold back spring that the cylinder plunger almost cleared the "push edge" of the shoe. That could have been interesting. Anyway, still a little brake bind, so I pull the master cylinder off with the intention of fitting a new seal kit (only £15 so no biggie if it's not an improvement). First thing on removal, reservoir is held on by cable ties. I see why later, it has been removed originally by breaking the plastic bolt tab at the bottom (normally held on by a 10mm machine screw). On separation though, I see they've sheared the front MC bleed screw. I have nothing to remove this, and given the length of time it's been there I doubt it would be any easy job anyway so I call garage. Garage send someone out, collect MC, remove bleed screw and fit seals for me. Unfortunately after fitting, I notice that heat has been used to remove the nipple. I'm really iffy about using the cylinder given that it's actually melted the alloy near the nipple (or is it just aluminium - not sure) - photos available if you want to see it. And additionally, union hole nearest bulkhead is threaded. In fairness the threading may have been me, but I doubt it - I'm generally very careful where pipe union are concerned and it started very easily by hand and then by small spanner (not enough room for anything longer 4 inches or so), but then tightens up about halfway in. Like I say though, didn't inspect that so could be me - guess I could look for evidence of aluminium oxide, but there's probaly not much mileage in that. These things are notoriously difficult to prove, and I think I'm better cutting my losses with the garage in question. What I think has happened is he's tried bleeding using the pedal and a one way valve and pushed it too far and "flipped" the seals. I have to say I have my doubts about flipping as there's not a lot of clearance, but I can see that a seal may be damaged or some detritus brought back to cause malfunction. There's more than a thread or two about this particular phenomena so I don't believe it's a myth. The rest is probably just one calamity after another. So there you are. I may be able to rescue the thread with careful application of a dremel, it's pretty soft metal and the pipe union itself is still good (pops into the front "socket" on the MC easy enough), but with heat being used I'm not convinced by the safety aspect. I guess we'll see tomorrow. Other than it's a new cylinder (over £100), or one from a breaker - anyone know one in Sheffield?

Ah well, noise gone again. Guessing maybe a stone stuck in the air gap/vent between the two friction plates.

You can only hear it with the window open, so definitely outside, and it's certainly not as loud as it was. Some days I can hardly hear it; it doesn't seem to be consistent. I have had a look for a foreign object in the tyre and couldn't see anything, but I'm going to have another look. Not grooved or drilled, just a plain flat surface.

And it's back again, though not as loud. Any ideas?

Oh well, that was weird. Solved itself - must have been something caught in the drive train somewhere.

Speaking of which, Haynes recommends removing the entire driveshaft to replace the outer CV joint. Whenever I've done this in the past I've only ever done it with te driveshaft in situ. Is there any reason it can't be done this way?

I think I've convinced myself it's the outer CV joint. On reinspection (with a lamp this time) I couldn't see anything untoward on the inner (or the outer for that matter, no obvious splits, tears etc). However if I throw it in gear, pull on the brake disc as far forward as I can to take up play in the gear box, then hold the driveshaft as still as possible, there appears to be 3-4 degrees of play in the outer CV joint and that certainly appears to be where the noise is coming from, so I'm going to order an outer and hopefully that's it. I always seem to answer my own questions on here; hopefully it's of some assistance to someone.

As per title, I have a regular clicking noise only audible when driving at over about 40 miles an hour in a straight line. Its frequency matches with road speed. It changes tone when turning left or right (and seems to almost disappear when turning in one direction (to the right from memory), though the turns are really only minimal since I'm doing 40-50 at the time. Probably got some strange looks driving down the dual carriageway weaving from side to side. Doesn't appear to be any noise or clunking on moderate speed full lock manouevres as far as I can tell. I don't think there's any doubt that it's coming from the off side front. I've had the car up on stands this morning to investigate. I can't find any play in the wheel and there doesn't appear to be any rumbling from the wheel bearing. On turning the wheel by hand with the steering in any position I think I can hear a rattling type noise that I would think is indicative of the CV joint coming apart. My guess would be the inner joint since it's apparent in a straight line. Didn't have a torch so couldn't see much of the inner CV joint - may have another look in a minute. Does that seem about right? All that said if it is the inner, for the price, I'm tempted just to pop one of these in: http://www.ebay.co.uk/itm/SKODA-OCTAVIA-1-9-TDi-TURBO-DIESEL-5-SPEED-OFF-SIDE-DRIVESHAFT-1998-2010-/171098170395?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item27d63ee41b since I've got to take the shaft out anyway, it seems to make sense and would cover both inner and outer CV possibilities. A lot less mess too assuming it comes assembled. Does anyone have any experience of J&R CV joints? A two year guarantee fills me with some confidence. Thoughts please?

Hi, Having just pulled my door apart to replace the window regulator, which died about 3 months after the passenger side door died (probably in sympathy, couples that have been together for a long time tend to depart in fairly quick succession), I have decided, while it is in bits to try and fix the door light, warning buzzer issue that I have. The difference is that it doesn't appear to be quite the same as the issues reported here. In short, when I open the door with the lights on, the warning buzzer and the puddle light come on if the door is only just open, but if you proceed to open further they will both go off (presumably at the same nanosecond, which I can't test, but intuitively that would seem to be the case). As you may expect, should you then close the door until it is just open a little, you can get the light/buzzer to light/sound again. Additionally, the following may be related (as alluded to on this thread). If you unlock, get in, close the door and are a bit tardy getting the keys into the ignition, the car will lock. Now this doesn't sound quite like any other problems, but since I don't know the working of the mechanism at all, I'm just asking of thiose better informed, whether they can think of anything that may cause this. I don't mind pulling things apart, soldering, welding, mechanical work etc. If anything the electrical side of things is my best area (which is a bone of contention with the wife since I keep fixing various white goods and televisions that she would rather spend a fortune on having new). So there you have it; any thoughts gentlemen?

I'll answer my own question. Remove wheel arch trim (two plastic screw type things). Remove support for luggage cover (two screws at the front and two at the back and one or two nuts in the middle). Release the top of the boot side trim so you can pull it down far enough at the top to get a socket on the 17mm bolt on the inertia reel. There's a clip at the back, and a screw or two at the top - no need to take it all out. Other than that fixing points for the seatbelt are obvious.