Mr Ponkerson

Might be worth clearing the code and run for a bit and see. Could well be a duff sensor or bad connectors.

first thing I'd suggest checking would be vacuum leaks and spark - plugs, leads, coils, dizzy caps. There are loads of things it could be, but these are probably the simplest and most obvious places to start. I had a similar issue with a mk3 ls400 and went through lots of things - turned out to be dizzy caps and a coil. It started intermittent for me, but ended up constant.

Hi folks, as my mk3 is my daily and I live just west of Edinburgh, I thought a set of winters may be prudent (I'm self employed so snow days aren't really an option). I have just bought a cheap set of standard wheels so am now looking to get the rubber to go round them. There seems to be an awful lot of choice and a vast array of prices, so I was just wondering who here has had 1st hand experience of running winters on a large rwd car and any recommendations/avoids like the plague. My priority will be grip in snow - there's a slope up to my house and down to the gym I work in.

Sorted! In the interest of completion for any future searches (a lot of threads I found had no conclusion), the issue turned out to be knackered dizzy caps. This also took out one of the coils so they've been replaced too. Happy man!

I'd love this (big fan of rat/survival style bikes - have "built" a couple for commuting on, not as extreme as this though). it would have to be about 2k cheaper to be worth a punt IMO. Change the passenger window, get rid of the skulls and I'd be happy.

Thanks chap, I haven't as yet - I've been using the wire across the obd terminal trick. The lad that's working on it has a work mate who thinks he may have an old reader at home so they're going to try that. I may have to bite the bullet and take it to Lexus for a reading though as I believe most obd readers can't read the old pre-obd2 Lexuses (lexi, lexopodes? Not sure what the group noun is). I'm fortunate in having a very helpful client who doesn't use his car much and, as such, lends me it Mon-fri. I'm starting to feel like I'm taking the P now though.

Thank you again sir - one more for the list and some more hope for future barging.

Thanks for the advice chap, I'll give them a bell after I get confirmation on whether my "the man" has found anything in the wiring or injectors.

well, sensors did naff all and the TPS adjustment just made the revs go way too high or low apparently. Boot wiring and general wiring check next. Still runs much better before it warms up apparently. Time to start shopping for something else though methinks

Yep - getting both checked and done. I'm also going to.put a list together of.other possibilities: Coils (doubtful as I unplugged one today and the revs dropped significantly, but worth checking) TPS IAC wires behind left hand boot lever Injectors Maf (although if it's unplugged the car stalls) Cooked and blocked cats Lack of sacrifices to the LS god Feel free to suggest anything you think I may have missed. Biggest frustration is the lack of CEL and/or codes

Thanks, am getting both sensors done on Wednesday

Cheers guys, had a full service done (maybe not fuel filter though, will check). Goes better at part throttle and higher revs, so will look at fuel filter too. Using the old wire across obd terminal trick and reading flashes on dash. The reason for coolant thinking is the gauge barely works (sometimes not at all). It's never really worked, only occasiinally coming off the bottom and never much below the lowest gauge line. The car wasll ok before the service with a slight misfire every 10-20secs while idling, things started going really funny a week or so after the service.

Just to add to the above, ecu now in - still rough idle (that gets worse as it warms up) and really hesitant and misfiry under load (if I bury the throttle it just bogs down at about 1500rpm). No error codes bar the battery one for abs (code 41). Starting to get really fed up and might just scrap the thing as I'm getting fed up of under 15mpg and spending money on non-fixes.

My 97 mk3 ls400 is still running like poop. Just had the capacitors replaced in the ecu, but have a feeling this will not resolve the issue. My next port of call will be the above as it runs much worse once warm (vacuum pipes checked, new plugs n leads, throttle body cleaned, exhaust fixed, maf unplugged to check - stalls) My question is, are normal motor factor parts like ecp good enough or are they really an oem replacement only option.

Thanks guys, I'll pass this on (and will recheck engine codes)

Hi folks, I've done a fair few searches on this and just after some confirmation that the fella working on my car is likely to be correct. My car has developed a misfire once warm and the revs drop below 1k. The idle is eratic/rough and it splutters on acceleration on part throttle and bogs down and splutters even more on full. This first started after the car was serviced. I initially put this down to non OEM plugs so ordered denso ones and got new leads - this made no difference. He's been looking more over this past week and had found and replaced a split hose (vacuum I think) which has improved things but it's still really not running right. He's certain it's due to the blowing exhaust between the two O2 sensors causing ecu confusion, but reading everything on here I'm not sure a simple.blow in the exhaust (the usual flange deterioration) would be enough? Or is it more likely a duff sensor, edu capacitor leakage? I had also managed to get a couple of error codes for the air intake temp.sensor and air flow meter. Not had time to check again since the hose has been replaced. As an aside (in case it's relevant), the temp gauge has never really properly worked on the car (occasionally kicking in to the bottom of the gauge but nothing more), he replaced this at the same time as the second set of plugs but nothing has changed except that it seems a little more willing to get to this bottom of the gauge point. Apologies for the long winded message

yep - I had read it too, but thought I'd missed something more sinister - as it happens I had misread one of the rust fails and hadn't realised it was a structural element and not just a component. It looks quite rusty underneath but some looks like peeling sealant and some could be road grime. Will be giving it a good clean when i get the chance. I also have a client who's a mechanic and he's going take take a quick look when he's next in the gym. I do appreciate your comments chap as it means I can deal with anything small in the near future before it becomes a serious issue. Dendonc - thanks for the heads up about treatment possibilities, will definitely be looking in to this

I crapped myself when i read this post as I thought I'd missed something major in the history so have just had a look under the car, it's definitely rusty so might post up a couple of pics to gauge people's opinion on how bad it is, a lot of it also appears to be peeled paint. i can see that a component has been replaced on the nearside.

On Saturday I flew down to Gatwick (from Edinburgh) to pick up this wonderful wafty thing from a nice chap who may occasionally frequent this forum, but is more often on the barge thread on Pistonheads (it's been christened Sherman by myself and the other PTs at the gym coz it is a big old tank of a thing). I had never been close to, let alone driven an LS400 before this. I had plenty of time to get used to things on the drive back up North though. Now my only regret is that I didn't take the plunge sooner. It has a couple of little foibles - non heating seat(s) - only checked the drivers but not too fussed, and the temperature gauge doesn't work so I'll be having a look at the wiring around the sensor at some point when there's less snow. Much like myself there are a couple of cosmetic flaws but nothing concerning - mainly a bit of paint fade and a couple of very small patches of surface rust due to stone chips. I'm finding I love this car more every time I drive it and can't wait to get behind the wheel - what a fantastic machine!

^ I always thought it was initial low temp running that increased wear rather than out and out mileage - once everything is up to temp the wear is much reduced, it's repeatedly using the vehicle below operating temp that increases wear (hence town driving not being seen as ideal compared to motorway)

The LS is looking like the most likely candidate. I had a very nice chat lockeyboy last night regarding his, and although it looks like it may not lead to a purchase, he passed on some valuable advice regarding the marque.

Under £2k ideally chap - had a couple of false starts using ebay etc

thanks chap - I have heard that is is rather refined and muted, however I'm happy to trade that against the reliability reputation as this will be a daily.

yep, that seems to be the case

thanks chap - that's quite tempting (although I do have a real hankering for a V8 of potentially LS or maybe GS vintage - guessing LS with my budget).