Early 406 diesel buyers guide pls?

[chasesdragons]

That's interesting. Is the HDI's DERV mpg so much better than the mpg of the XUD engine that the XUD needs to run veg oil to match the hdi economy?

Am I making an irrational decision buying an XUD where a 2.0 hdi may be better for high mile motorway use? I do about 28-30k, 90% motorways.

I can get WVO which costs 70ppl.

[Doggy]

My remapped 2.2 HDi can hold it's own with the today's diesels and has retuned 50 mpg over the last 6k miles. Others with similarly modded 2.0 HDi's are getting 5 to 10 mpg more and reasonable performance too. A 1.9 on WVO will certainly be cheaper, but it will involve you in filtering WVO, frequent fuel filter changes, the occasional in tank strainer clean. Just depends on how keen you are.

My bro ran a 1.9 on WVO for a couple of years, but now has a remapped 110. Despite his deeply cost-conscious nature, he wouldn't want to change back. He's getting 45 mpg around town and 60 ish on his trips abroad.

[rwb]

I had an XUD before my HDi and on the same 150 mile trip (Birmingham to London) the XUD would do 46mpg and the HDi would do 60mpg. So yes, you do have to run the XUD on veg.

Given the experience and expertise on here and other sites, and the high availability of scrap, I'm not sure that the cost of maintenance swings it for the XUD any more.

I think that the only reason for running an XUD now is because you can get veg oil for next to nothing.

For motorway use, if you keep it under 65 then I'd consider a Siemens HDi 90. They're very slow but very economical, and they're later models. If you're a bit faster then the HDi 110 has a slightly longer 5th gear and there is a 140HP map that you should be able to obtain for next to nothing. The 90 will cruise at 80 -- it's astonishingly capable once it's moving -- but it's unpleasant. It's the usual trade-off between fuel-efficiency and time-efficiency.

The 2.2 HDi would also be a good choice, but they're quite sought after, but definitely a better option than a cheap 407 because the two main problems on both these cars -- particle filter and dual mass flywheel -- are easier and cheaper to deal with on the 406.

[PeterN]

The 2.2 is nice to drive but I found mine very poor on fuel, in the 40s as apposed to the 2.0. Hdi doing 60+. Also believe it or not the emissions are lower on the 110 than the 90 making the tax cheaper.

Peter

[Rolebama]

I was in the motor trade for the entire life of the 306 and 405. Every 405 I ever saw had a Bosch pump, and the fitting of the Lucas pump on 306s seems random. Only thing I ever remember replacing on either were the usual alternator, starter and clutch cables. Occasionally I replaced fuel shut off valves/solenoids on 405s. Only saw early 406s, and found both Bosch and Lucas pumps. Only probs were as with 306 and 405s. I would recommend the 406 though as the 405 and 306s do get better mpg, it is because the 406 'sacrifices' a little mpg to give a heater that works. (405s and 306s tend to run cool in winter and hot in summer.)
On any old car I would check, or have checked, the radiator for blockage. Very easily overlooked when overheating problsms come up.

[chasesdragons]

Hi all again.

Thank you for the continued info. I am feeling much cockier now and am willing to wait for the right vehicle now that I know that there is little gain, FINANCIALLY, by holding out for an XUD than a 2.0 90bhp hdi.

I assume there are no other hdi specific issues apart from what was mentioned above especially electrical?

[highlander]

HDi engines run their fuel lines at extremely high pressure, so some components (fuel rail, injectors, and pump) are a lot more expensive than similar parts on the XUD engines.

Also, the HDi engines really don't like running on vegetable oil; because the fuel pressure is so much higher, the fuel system has a much lower tolerance for fuels of different viscosity than regular pump diesel.

Other than that, it's all good!

[PeterN]

The 8 valve Hdi is a very reliable engine, head gasket wise better than the XUD, the 2.2 and later 16valve engines are more complicated and therefore more prone to problems but as they don't use them in the 406, apart from the 2.2 that is not a problem. The 2.0. Hdi has no DPF either so even less to go wrong.

Peter

[highlander]

HDi 110 has a dual-mass flywheel too, doesn't it?

HDi 90 doesn't, and has no intercooler either. But didn't Sam's HDi 90 have the DPF for some weird bloody reason?

[chasesdragons]

Thank you again guys.

[rwb]

HDi 110 has a dual-mass flywheel too, doesn't it?
HDi 90 doesn't, and has no intercooler either.

Correct.

But didn't Sam's HDi 90 have the DPF for some weird bloody reason?

I never believed this because although ServiceBox alludes to the existence of a 110 with DPF (which we've never seen an example of), not so for the 90.

[chasesdragons]

Just a note to thank all of you profusely for you time and knowledge. I am now the owner of an 80k, 1998 1.9 td glx 406.


I look forward to clogging up the forum with questions!!

[rwb]

80k
That ought to be quite a find.
When do we get pictures

[chasesdragons]

My thoughts exactly. The last two years mileage show a 3k miles change. Apparently it is from a gentleman giving up driving due to age, I have yet to verify all this. Pics up when it gets dragged in

I need to scrounge up an electronic parts catalogue or service manual before I have a good look over for fitness of purpose

[gumby6371]

Excellent find there! the GLX is a relatively well spec'd model.
I'd advise checking for a timing belt change as it's a bit overdue on mileage and wwaayyy over due on age.

Sticky clocks, failing blower motors and drop links are the only issues I had with mine and all very easy fixes.
Glow plugs are a bit of a knuckle scraping job on them but fit quality and you'll only change them once.

Basically if I could keep mine running with my skill level anyone can

Looking forward to some pics and shout if you encounter any problems.

(I still have a few spares in the shed a Haynes and possibly an owners manual if you need them)