Engine Rpm

[jsj24uk]

Good afternoon people and Happy Easter.

Not that I have been on an economy drive or anything but for the past week or so I have been driving my LS430 round very gently to see what sort of a difference it makes to the MPG. So far I had a tank average around town and motorway of 32.5 MPG. Couldn't quite believe it myself as the best I got out of my old GS300 was 30MPG. These readings were taken from the tank average.

The only thing is, my LS never goes above 2,000 rpm. Is this going to cause the engine to coke up over time leading to premature oxygen sensor, catalytic converter failure or any other such related problems? It must think it has been bought by the manager of a matress company.

Also, completly unrelated, in the rear offside tyre I have noticed a nail which is well imbedded in the tyre. It looks to be just over an inch away from the side wall. Is this typre of damage repairable as I don't know how close to the tyre wall you can get before it isn't repairable?

Many thanks.

[Bigste]

If your engine starts suffering from the drive slowly syndrome it will be many tens of thousands of miles before there is anything noticable, if at all. The tyre needs repairing a.s.a.p. If it goes flat the end of the nail could damage the wall by being driven flat.

[steve2006]

The only thing I would mention is that due to "economical" driving my diesel van has had to have 2 replacement EGR valves apparently they clog up easier when the engine only does low revs consistantly.

I have been told to "flog it" occasionally to try and prevent this happening again.

I don't know if this theory applies to Lexus petrol engines but I do know that the EGR is a pain to replace!