Sunday's Breakdown of the Day

Something similar happened to me 3 days into my TD5 Disco 2 (auto), when a pipe blew off the auto box and dumped the fluid all over the M3 and the back window of the Disco Revs went up, speed went down - engine ran fine ;-) just didn't go anywhere fast Can you dip your 'box ? Good luck Mac

Books just wanna be FREE! See what I mean at:

surge

My best guess would be one (or more) of the ignition coils breaking down when hot. This could well produce ozone emissions, which gives a metallic smell. It would also explain the lack of power as the engine starts to drop onto 6 cylinders. (each coil fires 2 cylinders).

Check the coils are secure and all connections are OK.

If/when it does it again, if you can keep the engine running, try pulling one lead at a time off the spark plugs. If it is a coil problem then 2 of the cylinders will make little difference to ot's running.

Obviously I'm assuming this is a standard 4.6 setup with no distributor !

cheers

Dave W.

Thanks Dave. I wondered whether the coils were a possibility but deliberately didn't mention it in case I biased the answers (no, really!)

The trouble is, when it does it, it's usually somewhere where it's totally impractical to do any testing (like the middle of London), and by the time you've got it somewhere where you can mess around, it's back to normal.

I think I'll take it into the dealer anyway - I've already learned that I can do more harm than good messing around with a P38. That'll mean paying main-dealer parts & labour costs but at least I'd have some degree of peace of mind.

But just in case - how do you test a coil?

Thanks, David.

Substitution is the easy way in this case... trouble is that, if you have the 4 individual coils, they are only available as a single assembly which costs the best part of 300 quid genuine.

The later type has two coils with 4 outputs each, these are a bit more reasonably priced at about 30 quid each and they are available seperately.

I'm not sure whether it's feasible to replace the 4 coils with the later assembly, the whole assembly with 2 coils and the mounting bracket comes in at just over 100 quid so it would certainly be a cheaper option !

cheers

Dave W.

On or around Sun, 15 Feb 2004 21:29:36 +0000 (UTC), Dave White enlightened us thusly:

if it's a vaguely normal coil it'll have LT and HT windings, and there should somewhere be figures for resistance. However... if it's breaking down when hot, you won't be able to test for that. Does sound uncommonly like an ignition fault though, it's unlikely that you'd have a fuelling fault which would affect both fuel systems the same way.

was the engine a recon 10K ago? seems to me like it was either a naff recon or more likely a naff fitting job.

bleedin 'ell. And I was pissed off at 70 quid for a pickup for the distributor on mine, which turned out not to be faulty.

It was a brand new Unipart genuine short engine. But I presume they wouldn't have changed the coils?

On or around Mon, 16 Feb 2004 18:43:33 -0000, "David French" enlightened us thusly:

I doubt it. strikes me that installation of engines on these modern vehicles is something that requires a fair bit of knowhow, who installed it?

short engine of course has none of the ancillaries, manifolds, fuel gear, ignition or anything. so all that is probably original.

A main dealer who I'm not going to name as I'm chasing them for some money for something else...

On or around Mon, 16 Feb 2004 19:49:59 -0000, "David French" enlightened us thusly:

fair enuff.

I'd go with a local expert, if you can track one down, every time. Just occasionally, you find an expert working for a main dealer, but it's rare.

Ideally, you want someone recommended by word-of-mouth.

wonder what's so boodly special about the coils that they have to cost 300 notes? normal coils are about 20, ISTR. And I see Chris Perfect has some extra-posh shock-resistant ones for trialling for about 45.

thinking about yours without knowing much about the systems, the faults all look to be pointing to ignition, and a coil breakdown when it's hot is something that can happen - there's a good chance that your coils are original, and have thus been around a few years.

As to whether the later (cheaper) ones fit, that probably depends who you ask - the main dealer will undoubtedly tell you "no".

I've fergot where you are. Personally, I've found J.V.Like very good, main dealer or no, although I've only ever bought parts from 'em, not actually had work done. Their parts bods seem to know what does what, and they didn't baulk at ordering in all 3 kinds of electronic ignition trigger/baseplate things 'cos the parts catalogue doesn't tell you which is which (silly, really - if they just had a picture of all 3, they're easily distinguishable).

Bagshot, Surrey. Nearest main dealer is Royal Ascot, followed by Lancaster in Guildford. Nick Kerner is about 10 miles away.

David

On or around Tue, 17 Feb 2004 10:57:10 -0000, "David French" enlightened us thusly:

heard good things here about the latter, thobut whether he's a P38 expert, I know not.

I guess in the end yer damned if you keep it, and damned if you don't. Personally, I hate having mechanical things beat me, so were it me I'd probably keep it and keep trying to hunt the fault. I'd give moderate odds that there's just one fault, somewhere silly - with the modern electronics one thing being flaky (such as a sensor somewhere) can throw many things out of kilter. Even first-generation electronics such as are on my things (old-fashioned distributor with electronic trigger and amp instead of points) can be a pain, as witness I've now got a new amplifier, trigger, baseplate and rotor arm, only the last of which actually needed changing, it seems. so that cost me about 100 notes more than it should have in an ideal world, but faced with a thing making no sparks at all, you don't automatically think of a faulty rotor arm, especially as there was nothing visibly wrong with it.

best of luck, whatever you decide.

Poorer if I keep it, poorer if I don't.

I took it up to James French today. Very helpful indeed. Their chap Steve seems to really know his stuff, although time will tell if the problem's fixed. He gave me a lot more confidence than any other dealer I've spoken to so far.

He thinks it's a persisting crank sensor problem so it's having that looked at tomorrow. Fingers crossed. He also managed to find some other issues I wasn't aware of, and reassure me about some things I thought might be causing problems but aren't.

The Autogas still isn't running properly, according to the diagnostics, so I'll take it back to Nicholson Mclaren for tuning (they did suggest this actually, just haven't got round to it).

However, even if I get this fixed and it all runs fine, the sheer costs of maintaining a P38 (given it will get up to about 200K miles by the time I plan to get rid of it) make me think I may have the wrong car. I test drove a Disco TD5 and a Defender TD5 at French's, and I'm very tempted. The catch is, it will cost me even more to switch to a Disco TD5, and more still for a Defender. There's still the option of a 300Tdi (either car) but I'm worried this may be going to agricultural considering I need a good, presentable car for work (you Series owners can stop laughing now).

So... stick with the P38 and take a risk that it will cost megabucks, or spend money now on a TD5 in the hope that I'll save in the long run?

David

Re-reading that I realised some tdi owners might find that insulting - sorry!

It's just that I have to think of my employer, who after all pays for all of this stuff, and unfortunately in the line of what I do, you have to be seen to be projecting a certain image to customers. Taking somebody out for lunch in my old 200Tdi was just not on, really. I have to make sure whatever I get is going to still be presentable in 3 years time, seeing as I don't want to have to change again.

Ironically, I think you can get away with it fine in a Defender, providing it's shiny, as it's seen as a bit of an icon.

You can get away with a battered one - as long as it's not machoed up:- "So you actually *use* it off road?........" worked a treat at contract interviews, avoiding tricky questions like "What does this bit of 'C' code do..... :-)

Richard

On or around Tue, 17 Feb 2004 20:51:40 -0000, "David French" enlightened us thusly:

Hobson's wossname, innit. but vehicles always are.

FWIW, the 300TDi disco is pretty good on the "presentable" front - engine's nice and quiet from inside, pulls well if you tune it up right, and can be tuned further to equal the TD5's output if you fancy spending the money (bigger intercooler and a tad more boost, basically) but in fact if it's all up to spec and p[roperly tuned it's plenty fast enough. Ours will happily sit at 85 on the motorway, and it's quieter than my V8 110 at 70.