Roger Blassberg

Come to think of it, where is the feed to the water temperature gauge? Is it from the yellow sensor, or is there another one somewhere? Best wishes RB

Come to think of it, the judder can also be caused by weak or broken engine mounts; it's a very common problem. If the engine is jumping about there many be noises from such things as the exhaust system being bashed into the body of the car. Look especially at the front mount; start the engine, engage 1st gear, apply the handbrake and gradually engage the clutch. If the front of the engine moves up by very much or the mount is obviously broken, that may be your problem. "What else needs doing?", you ask. How many miles has the engine done? Are the timing chains healthy ie rattle-free at about 1500rpm? If not, the time to do them is when the gearbox and clutch are off. Parts are about £250, plus a few more hours labour. Once done, you can forget them for the next 100 000 miles. I wish I could forget mine!! Best wishes RB

Your temperatures didn't sound that high, but it's always better to safe than sorry. If the warning light flashes but the coolant is up to the Max line, the tank sensor is faulty and needs to be sorted out. Golddust says that the sensor is integral with the tank - I don't know for sure. The blue two-terminal sensor will not affect the running temperature - it is purely to report to the ecu for fueling. The yellow (middle) four-terminal sensor on the thermostat housing may be the culprit. It may have been substituted in the past by a black sensor, but it will still have four terminals. It is reasonably easy to get at, and cheap to buy. Looking at the engine from the front, it is to the right of the inlet manifold fitted into the thermostat housing near to where the bottom hose goes in. It is held in place by a 'C' clip which you gently ease out. Don't go at it like a bull at a gate because these housings are brittle and easily cracked.Prepare to lose your coolant. Replace the sensor and the rubber 'O'ring. Top up with G12+ coolant which is compatible with all other types. Do NOT mix G11 with G12, use only G12+. If you have a/c there will be a third sensor (black), but again this will not give the problems you describe. The fan thermoswitch is on the right side of the radiator, below the top hose connection. It is a brass hexagon plug, about 28mm, maybe more. Again, you will lose coolant when removing this. It controls the two speed fans during normal running. I forget the temperatures at which the fans cut in and out; the sensor is again fairly cheap and worth replacing anyway if you have any doubts about it. Have you checked that both fans are turning? One is driven by an electric motor, the other is driven by a small belt from the first one. If you in St. Albans again, let me know if you need further assistance - no guaranteed cures, mind you. Incidentally, I get most of my parts from Murray McDonald in Hatfield, opposite the Galleria. Best wishes RB

Temp sensors on a VR are; -coolant level; on the expansion tank. This controls the flashing warnig light. -temp sensors to ECU (blue), to overrun pump/fan (yellow), and to aircon if you have it (black); on thermostat housing. Fixed by circlips and seals. -radiator fans (brass hexagon screw plug); on radiator core, between top and bottom hose connections. Best wishes RB

Does it slip, in the higher gears and going up hills in particular? If so, either the pressure plate is weak or the driven plate friction surface is worn out. Does it judder when pulling away with minimum revs? If so, the cushionsprings are broken or the clutch faces are distorted. The squealing on take up may be worn linings causing the rivets to wear into the pressure plate or the flywheel, but I would expect that to be accompanied by slipping in the higher gears. Grinding as you go into 1st gear could be either worn synchromesh in the gearbox itself, or a dragging clutch caused by a worn release bearing or contaminated friction linings. £436 is a tad pricey I would say. A complete high quality (LUK) clutch set is about £100, so over £300 for labour - OTT in my view. Best wishes RB

Good grief !! We are talking about a system that is there to save your (and others') lives, whether you like it or not. If you want to skid uncontrollably into a tree, I suppose that's your business but I would rather you don't do so into me or anyone else (in that order). End of rant. Best wishes RB

Briggy, Pinking is an irregular very high pitched clatter which usually occurs when accelerating hard from quite low revs, especially when the engine is hot. Timing chain rattle is a different noise, but, admittedly similar, but generally of a lower pitch and coming very spcifically from the gearbox end. I think the way to tell one from the other is this - if the chains are rattling they will do so with the engine off-load (ie out of gear, sitting on your driveway) and particularly at 1200-1500 rpm. Pinking will not occur under these circumstances, only under load and over a wider rev range. Pinking was a problem with mine until I had both knock sensors replaced. They are relatively expensive - about £125 for the pair (one front of the block, one back.) The real problem is getting at the front one as it is thoroughly buried under the inlet manifold, which needs to come off to get at the sensor. Make certain that the through-bolt on each sensor is done up to precisely the correct torque of 15 lbf-ft, or they don't work properly. Too loose - no signal, too tight and you wreck it. Also, the contact surface with the block must be scrupulously clean. VAGCOM will detect a discontinuity in the wiring but not a damaged or partially inoperative sensor, a loose bolt or a poor contact surface. If using Optimax has made the problem less frequent, maybe it is pinking; but the knock sensors should be able to cut out pinking even if you are using 95 octane, so maybe they are not working as well as they should. Come back to me if there are further questions. Best wishes RB

I have a '94 LHD Passat GT (supplied in Germany) with cloth sport seats (high side bolsters on seat and backrest) and the side bolster on the driver's seat is worn through, the foam has gone through too, right to the frame. My general question is this; is anyone able to advise if cloth seat covers are available, as well as the foam bolsters? I can provide the upholstery code from the original order form. If not, I suppose I can patch the hole by robbing the material from one of the headrests. Best wishes RB

The fuel tank certainly goes light at that speed - allegedly. Best wishes RB

1 cm below maximum is probably accounted for by occasional evaporation and may not be a leak, especially if it has not lost more since the top-up. Incidentally, did you check if the water in your footwells was coolant (sticky, sweet-tasting), in which case your heater matrix may have a small leak. If your engine is oiling nr. 1 plug (and maybe nr. 6) you may be looking at ovalised bores rather than worn valve guides. Do you get grey smoke under acceleration (bores, rings), or immediately after running on a closed throttle down a hill (valve guides/stem seals)? How many miles has the engine done? Best wishes RB

Be careful, the ABS pump produces very high pressures. You don't want hydraulic fluid in your eyes, so wear total surround eye protection. It's not soppy, it's SAFE. Best wishes RB

Does anyone have a reliable confirmation of the source of Sainsbury's super unleaded 97 RON ? There's a great deal of discussion goes on about the relative merits of supermarket and branded fuels. I am fairly confident that Sainsbury, Tesco , Morrison and so on, do not each have a blending plant, so they are most likely buying it from the big boys. It leads me to believe that there is a lot of hype surrounding the marketing of the different brands. The British Standard for motor fuels is presumably being adhered to by all the fuel that is marketed, and I assume that that British Standard was developed in conjunction with the engine manufacturers. So, the question in my mind is, why not use supermarket fuel if the octane rating is appropriately high? On the point about Optimax losing its additives over time, is there not then a case for having a sell-by date imposed, just like there is on other perishable goods? Best wishes RB

If this carries on, I'll have to put the parent lock onto this forum....... Best wishes RB

Thanks to all for advice; I have now got the 2nd part of the Car Mechanics article, (Jan 05 edition), too late for the first part so I'll get the back issue. What's all this about simplex/duplex upper chains? I assume that mine is duplex currently (engine manufactured late 1993/early 1994). Is this compatible with the later type Mk 4 tensioner or would I have to change to simplex top chain and sprockets to use with it? Instinctively, I feel safer with a duplex chain, but I suppose the change was made for a reason on the later engines. The article is a real doom-laden tale. What is the experience of people here of having to relace the bottom chain sprocket - complete with crankshaft !!!!! Best wishes RB

The blade comes off very simply; pull arm back from screen to over-centre position, pivot blade to 90 degrees to arm, pull blade off if it hasn't already fallen off. Mine judder a bit, especially in light drizzle, and calm down after a while. The improvement in the wiping is more than adequate compensation, though. Best wishes RB

Oil filter tool?? Do you mean a chain wrench? You will gouge the piston and tear the dust seal with anything like that. After that, it's just a matter of time before the caliper siezes up. Best wishes RB

The coilpack fires both cylinders in the pair simultaneously, one only as a power stroke. It is necessary for both HT leads of a pair to be properly earthed for either of them to function. A faulty HT lead on one of a pair will cause a misfire on the other one of that pair, apparently showing two faulty cylinders where only one is in fact faulty, so maybe you have just one leaky HT lead. Am I teaching Grandmother to suck egs?? Best wishes RB

I believe that the 2.3 litre engine in the Galaxy is a bored and/or stroked version of the 2.0 litre 4 cylinder, not the V5. Best wishes RB

Timing chains are getting a little noisy on my '94 VR6, especially at around 1500 rpm. I want to get all the bits together before I start the job and I have read numerous threads on this subject. I recall somewhere talk of using modified/non-standard parts - was it a MK4 Golf top tensioner? I would be very grateful if someone could post a full list of the genuine OE parts which I will need together with their part numbers. In return I will undertake to do a "How to..." for the benefit of others. I'll be changing the clutch as well. My question is, do I have to take off the flywheel to get the chains out? It seems logical that it is necessary unless the bottom chain is so long that it can fit over the flywheel in situ. Is the flywheel simply bolted/dowelled onto the crankshaft flange, or is it on a taper like on a Mini? How best to support the engine when the transmission mounts are disconnected? Is the temporary beam support spanning between the wings available to buy or hire from anywhere? Thanks in anticipation. Best wishes RB

Go to the Sykes Pickavant website. The wind-back tool is in there, so it's still available; it's a first-class addition to your tool kit. Make sure you get the correct flange for the piston recess pattern you have, or splash out on the full set. Best wishes RB

If you increase the master cylinder size, the pedal effort will rise by the square of the diameter increase. eg a 25mm m/c will need about 18% more effort than a 23mm m/c. On the other hand, the pedal travel will be reduced by the same proportion. Best wishes RB

Maybe the rush of water under the car disrupted the wiring to your lambda probe. Best wishes RB

I found the blue sensor and changed it - disconnect the top hose which enables the a/c hoses to be pushed out of the way, then remove a plastic cover and a small bracket and all is revealed. Only thing is, it turned out to be the lambda probe after all of that. So all is back to normal. Thanks for the advice. Now the chains are starting to tinkle, so it's time for major surgery. Does it ever end?? Best wishes, happy 2005, RB

A new problem. The engine idles roughly, and stalls at junctions etc. The fuel consumption has sky-rocketed. The plugs are black and sooty. The exhaust smells very much of a rich mixture. It seems to be running a little cooler than usual during normal driving, although it does get there when in traffic, up to the point of the fans coming on. It all sounds like over-fueling and my first suspect is the blue temperature sender on the thermostat housing. Will that show up on VAG 1551 ? I don't suspect the MAF - disconnection of that causes a very noticeable worsening of the engine running. But how to get at it? The aircon hoses and inlet manifold seem totally to obscure it. Do I need to take off the inlet manifold. I just had the knock sensors replaced and that necessitated all of the manifold coming off and a disproportionately huge bill. I will not be amused if I have to repeat the process. It's worse than working on a Mini !! Best wishes RB

I would use a piece of thick plywood between the sump and the jack. Best wishes RB