johnatg

There's a bit of faulty geometry on IS models at full lock - Ie the geometry isn't quite to Ackerman rules which mean the wheels should follow parallel arcs when the wheel is turned - or not quite in the case of IS. It only affects full lock (or near) positions and often the tyres iron it out. Sometimes you feel it as a single knock or a series of knocks as the tyre slips on the road. And it can depend on whether you were moving forward (or backward) when you were turning the steering wheel - you always should be moving as it greatly reduces stress and wear on the inner and outer track rod joints and the steering rack. Nothing to worry about.

Yes the big oval things are the silencers. I'm not sure what Lexus use. There are two common methods - one is where the panels are simply bolted to the floor - the bolts screw into tapped holes or captive nuts. This is probably what Lexus use. The other method is where there are plain studs protruding from the floor and the panels are held to them with starlock washers. The panels have probably corroded around the fixing holes, so now you have big holes with rusty edges. You can usually effect a repair by using repair washers - they are about 3cm in diameter with a 6mm hole. That will cover the damage. Or you can make up a cross with perforated strip (perforstrip is one brand - accessory shops sell it or other brands) as big as required to extend beyond the damaged area. You may need new bolts and the repair washers as the holes in the perforated strip are quite big. You will probably need new starlock washers as they often break when you prise them off the studs.

No - it won't make any difference - except that you'll be able to get underneath - warning - DO NOT RELY ON JUST THE JACK - USE AXLE STANDS OR SIMILAR. You may be able to work around the silencer, or you may need to remove the silencer.

All the exhaust ends are round. The tips are just push-on stainless steel (note: not chrome) trims - and they are all the same (from 2005) if they haven't been removed or changed. BTW - those 'standard' rear silencers etc sections in the diagram are after market and quite cheap - far from standard. They may, or probably will not, be as quiet as original Lexus ones and almost certainly not as durable. But original ones cost an arm and a leg.

If only life (and driving) was that simple.........

The car hit the van - my point exactly. But I think the van driver wasn't completely free of blame - maybe he misjudged the speed of the car. Sent from my PSP7551DUO using Tapatalk

Any or all of those might be a good idea - and or get the new sensors tested with an oscilloscope - after all, you've implied that you think the old sensors are past their best anyway.

AFAIK the only way to test the O2 sensors properly is in situ with an oscilloscope. Sent from my PSP7551DUO using Tapatalk

Your calculation of the difference in our lambda readings is not valid - there is a world of difference between 1.000 and 0.997. 1.000 indicates exactly stoichiometric combustion - 0.997 is right on the limits of spec but indicates a rich-ish mixture - ie too much fuel for the oxygen in the cylinders. (And your high-ish HC reading concurs). I know your error codes are showing too lean, but your lambda is showing too rich (if it's correct) That can be caused by a variety of things - eg blocked air filter, slight misfire - plug or coil, faulty temperature sensor (the one feeding the ecu is not the same as the one which drives your temperature gauge), etc. I think you need some tuning diagnosis rather than relying on error codes, because they are all over the place. Maybe try a mobile tuner with an oscilloscope - that can also show the actual output from the O2 sensors. Are you using Techstream to retrieve the codes, or a generic code reader? The emissions are not wildly out (and indeed are within MoT specs), so the problem is likely to be minor and intermittent at the moment. I can't explain the error codes reading as they apparently do, but they can sometimes be quite misleading.

Your readings are within MoT limits but they do indicate an issue - and it could be any of lots of different things. Lambda represents the ratio of the amount of oxygen actually present in a combustion chamber compared to the amount that should have been present in order to obtain "perfect" combustion. Thus, when a mixture contains exactly the amount of oxygen required to burn the amount of fuel present, the ratio will be one to one (Ll) and lambda will equal 1.00. If the mixture contains too much oxygen for the amount of fuel (a lean mixture), lambda will be greater than 1.00. If a mixture contains too little oxygen for the amount of fuel (a rich mixture), lambda will be less than 1.00. The above is cribbed from an excellent article (lecture notes?} here: http://www.austincc.edu/wkibbe/lambda so rather than write my own essay I refer you to that!

Sounds to me as if the van driver misjudged the speed of the car approaching and decided he had time to enter the roundabout ahead of it's arrival. After all, at roundabouts you should 'prepare to stop - be ready to go'. Roundabouts are not there as some sort of fun chicane to be negotiated as fast as possible - they are there to slow traffic to allow safe merging. Too many people treat them as the former, with the attitude - 'my right of way, |'m coming through'. The fact that the car was unable to stop when the van pulled out in front, but swerved and collided with the rear of the van rather indicates excessive speed to me. Van driver's mistake, car going too fast. 50/50. But I wasn't there, so who knows.

Here's my print out. A bit of interpretation: Fast Idle test Engine RPM Allowable range 2500 - 3000 Actual 2823 CO Allowable 0.2% Actual 0.0% Hydrocarbons Allowable 200ppm Actual 5ppm Lambda Allowable 0.97 - 1.03 Actual 1.00 Natural Idle test Engine RPM Allowable range 450-1500 Actual 736 CO Allowable 0.3% Actual 0.0% My car is 2006, 63000 miles. Still with original spark plugs.

That's sort of what I was getting at coming from a different direction. But I suspect a seizure - these belts almost never break. A sudden seizure may have broken it. Or a gradual one but then I would have expected noise. Sent from my PSP7551DUO using Tapatalk

Did it stop when the belt broke? It should run - the belt doesn't drive anything vital to the engine running in the very short term. See if it runs with the belt removed. If it does, it points to one of the items driven by the belt having seized - aircon compressor, alternator, tensioner, idler pulley, water pump? Don't run for more than a few seconds without the belt on - no water circulation If it doesn't then you have another problem and we need diagnostic codes.

Here's a self-explanatory drawing of how to release (and keep it released) belt tension. Simply use a ring spanner on the bolt you mention! Make a drawing of the routing before you remove the old belt.

It switches on a heater which quickly defrosts the bottom of the windscreen, especially where the wipers lie. It also helps a little with general demisting of the windscreen in conjunction with the main demisting function of the heater/climate control system.

Don't they just heat up if the outside temperature sensor detects that the temperature is less than about 4 deg C or so? They do on mine.

It's the white spray grease I suggested you spray on to it! It's white - the clue is in the name!

Likely it's salt, or the results of salt acting on the metal of the catch. I'd suggest spraying with WD-40 and then with white spray grease.

Do you straddle speed humps? That wears inside edges of tyres quite badly. The alternative of course - to have one side in the centre of the hump and the other side on a flat bit - risks suspension damage unless you slow right down - but then that's the intention!

Old brake fluid won't really affect the feel of the brakes - it's still not compressible (unless it boils because there's too much water in it, then you get more or less total brake failure). Lexus specify that brake fluid should be changed every 3 years/36K miles - many manufacturers specify every two years. Garages (maybe even dealers) often don't bother. Soft feeling brakes could be due to air in the lines - did the local garage bleed the brakes? Do they harden up substantially with an extra pump on the brake pedal - that's a good sign of air.

Maybe but don't kid yourself - if you buy any 7-8 year old car and sell at 10-12 years, the difference with or without dealer SH will be negligible IMHO Sent from my PSP7551DUO using Tapatalk

BTW - I just noticed the bit about 'carrying on with Lexus servicing'. That will be expensive and totally unnecessary - the only things needing regular attention are oil changes and oil, air (only very occasional) and cabin (pollen) filter changes - after market filters work fine at a fraction of Lexus prices and oil is oil. Buy your own fully synthetic 5W-30 on eBay along with filters etc and get a good indy to do your servicing if you can't do it yourself. All the other servicing 'work' is/are inspections - hell, the MoT covers most of them. Lexus dealers don't do the essential brake caliper maintenance, and they charge full price for any parts they consider 'needed'. You can buy filters, tyres, brake pads etc much more cheaply from the after market and they work just as well - often they are the same parts in a different box. Using any dealer for any car after it's out of warranty is throwing money down the drain, IMHO - they are geared up to maintain cars within warranty and change 'units' - they don't consider or attempt any suitable fixes which require a bit of dismantling, repair and reassembly. A good indy will seek the best/lowest cost compromise to deal with problems.

There's no reason why an IS250 should cost you any more to run and maintain than a Honda (Accord?). IS250s are at least as reliable as an Accord (which I know is very reliable indeed) I guess your commute is about 30 miles each way - that should be enough and not too much to keep the car in good nick for a long time. The comments above cover pretty much anything which could potentially go wrong - the brake calipers do need their regular cleaning/greasing, but eg my exhaust is still original (from 2006) with no signs of problems (I probably shouldn't tempt fate like that!)

I'd say you have a cat problem. I'd try a can of Cataclean in half a tank of fuel and give it a 50 mile blast on the motorway in 4th at 70mph. Sent from my PSP7551DUO using Tapatalk