Oxygen sensors, Cold engine tap, LPG conversion - 2002 XJR

Marko the O2's are like spark plugs, they're in a harsh environment and do wear out eventually, your's is a classic example, posts a code after a long run coming off gas.

Just buy a code reader (if you haven't already I'd recommend a memoscan 581, ebay £50 or so) and clear the code. If it becomes a permanent warning then buy the oem unit and replace.

Cold engine tap, first off - drop the s/c belt, see if this removes the tap - then it's look into the tensioner and idler bearings and s/c and belt. If not, then it's time to look further. The May 2002's a well clear of the plastic tensioners, indeed they have the latest and greatest 4.0s/c units with all metal timing parts and morse style silent primary chains, so it won't be a timing issue.

For the LPG - get the best you can afford, I've heard Remarno? Italian kits are the best - also talk to go-lpg these lads are the no.1 in fitting LPG to Jaguar's and always advertise them in the Jaguar Enthusiasts Club magazine, if there's anyone who can tell you about VSR it's them.

How's the de-roof car? finished?

Cheers Sean.

Check engine is a pretty regular affair already and as the LPG fitting will rely on the oxygen sensors I was thinking of swapping them now. Best part of £400 a pair for genuine pre-cat ones from British Parts though! £350 +VAT EACH from a dealer...

Good tip on S/C belt etc. I'll inspect when I have the S/C off for the LPG install. You rebuild these, right? Anything special to look for/inspection manuals out there? Worth ordering up bearings/seals at 145k by default or should it be fine? It's been fairly well kept (FJSH to 100k in first 3 years, independents x4 thereafter) and mostly seen chauffeur use.

LPG bits are currently en-route from Poland, last seen in Germany. Stag 300 Premium ECU, (unlike the Italian AEB based stuff incl Romano, it's truly sequential and the software is open/not locked to any particular brand of sensor/injector etc) HANA injectors (unlike the Italian stuff these are purpose designed for LPG, rather than pneumatic valves with different seals thrown in and a drilled piece of pipe as a metering orifice), twin "240 kW" KME vapourisers (no single vapouriser is capable of feeding a supercharged motor; the ratings on them are nominal and you've got to supply fuel for the gross engine power excl supercharger loss, and for an extremely rich air fuel on the supercharged engines at full chat - the equivalent of 500 bhp naturally aspirated I reckon), the flashlube system, and a bunch of other top-notch goodies. Tank is a secondhand one though; 95 litre Stako multi-hole toroidal from a Range-Rover with JIC fill hose rather than 8 mm and 8 mm outlet rather than 6 mm. ~£1150 in parts, at Polish prices. £1500 at UK prices.

I was going to fit a cheapie AEB system (King), with cheapie injectors (OMVL), a single vaporiser then use petrol addition at higher loads, and no flashlube system. This could be bought for under £600 all in from Poland but the more I thought the less I liked the idea of this on a daily driven supercharged car. Ok on a naturally aspirated one but you really don't want to chop and change fuel at full chat, risk burning valves, or be replacing injectors every 20k as you need to with the cheapies.

Steve @ Go-LPG seems to be an absolute cowboy and a bully-boy that only does the right thing when forced to by a judge...

Rubbish workmanship:
LPGinfo.co.uk
LPGinfo.co.uk

To fit a totally inadequate/inappropriate front end:
LPGinfo.co.uk
LPGinfo.co.uk

A bully boy:
LPGinfo.co.uk
LPGinfo.co.uk

But can do the right thing occasionally:
LPGinfo.co.uk

If you've got a naturally aspirated car, you only ever use 150 bhp or occasionally 200 bhp, and you wouldn't know a safe/tidy install from a botch job, then you'd be perfectly happy with his services. That description probably applies to a lot of his Jaguar customers - they're generally very nice people and not too demanding. He may also have learned a thing or two (at customers' expense) over the past 6 years, but I can't bring myself to trust anything that the guy says...

One I'm convinced actually does know about the supercharged Jaguars is Simon at LPGC:

LPGC Yorkshire Autogas LPG Conversions - Home Page

Didn't waste his time by asking for a price, but I should imagine £2k for a naturally aspirated vehicle and £2.5k for a supercharged vehicle is about the going rate.

Topless 8 is still a work in progress; going to tackle again in the first two weeks of August. Requires paint and an interior before we IVA it. Will probably need a new engine to get through the IVA as the one in there is essentially toast, but we'll see what it fails on first then present for re-test.