406 Turbodiesel A Bit Slow--Any Quick Fix?

nickmurphy · Post by **nickmurphy** » 03 Aug 2007, 13:39

i've got a P plate 406 td which has got the 1905cc engine--just seems a bit slow to me--it's totally reliable and at 162000 miles it really owes me nothing-is there a way of upping the speed a little-just doesn't have that zip that my old 405 had--i've read you can fiddle with the egr?? i'm a bit clueless but if somebody can tell me what to look for i'm happy to risk the engine and do it-i have put a new air filter in and some injector cleaner
cheers in advance!

caveman_si · Post by **caveman_si** » 03 Aug 2007, 14:27

The way forward is:

Filter change: oil air and fuel and an oil change. Give it a dose of injector cleaner and an italian tune up. Also check the brakes are not binding (I had that problem on my last car)

Dont forget to check tyre pressures as they make more of a difference then you think.

If it still doesnt feel as urgent then its time to get it professionally tunned. (you could do it yourself but for 100-150 why not pay someone else and get proper power readings and know its dones right)
I think the 406 is heavier then a 405 but has the same engine so i think it will a smidge slower anyway.

I believe Gav from the derv doctor in Ashbourne is supposed to be very good and reasonably priced but ive never used him. http://www.dieseldumpvalves.com/contactus.html Mine is going in once its running again and everytthing has been bedded in properly. Im sure my last car a 405 had been done as it went like the preverbial and was better then other 405s I have driven so I want the same for my 406.

Good luck getting the umph back

nickmurphy · Post by **nickmurphy** » 03 Aug 2007, 22:02

thanks for that-i'll get the oil anf filter and fuel filter done in the morning-should be easy enough even for me!

bcfc red · Post by **bcfc red** » 13 Aug 2007, 20:20

nickmurphy wrote:i've got a P plate 406 td which has got the 1905cc engine--just seems a bit slow to me--it's totally reliable and at 162000 miles it really owes me nothing-is there a way of upping the speed a little-just doesn't have that zip that my old 405 had--i've read you can fiddle with the egr?? i'm a bit clueless but if somebody can tell me what to look for i'm happy to risk the engine and do it-i have put a new air filter in and some injector cleaner
cheers in advance!

Had the same problem with the hdi,thought i was driving a moped!
quick e mail to celtic tuning and the chap came with his computer,does whatever he does and then invited me for a test drive. It was like driving a different car, i also tow a big caravan and it struggled to cope before the remapp, now it eats the hills for breakfast! Am well happy now as i was toying with getting another car because of the caravan,so saved myself shedloads of dosh! It was £300 to be tuned, but i would recommend them without hesitation. Don't know if you want to spend that much,but i am glad i had it done.

treky9.9 · Post by **treky9.9** » 04 Feb 2008, 10:15

I had a similar problem with my 306 (XUD 9TE).

In the end I spent a few hours with the intercooler off making sure that all the seals were in tact.
The problem was the rubber tube that goes from the front of the intercooler to the fuel pump, it had split around the back edge. This as my investigations revealed is the fuel diaphragm, basically when the turbo comes in the preasure builds up in the intercooler, which via the tube opperates the fuel diaphragm and increases the fueling giving the correct boost power.

It is now running like a rocket again and at 213K I'm really enjoying it. Now I'm no expert but these engines are purely mechanical (no remapping etc) so I would say after a standard filter & oil change have a good check of all rubber tubes that could have perished (fuel, injectors intercooler etc).

Oh, I also use the Millers power plus additive and XFE every 6K.

Good luck

busastars · Post by **busastars** » 14 Feb 2008, 01:12

I know this may sound stupid but is a true story about my Xantia 1.9td.

I bought the car last year, it had service history just over 100k and two owners.

Now the owner had the car for about 7 years and tried it for towing but sold it to me as he replaced it with an Audi for towing as the Xantia had no guts in it.

I drove the car hear and there but it was the wife that used it all the time. It did feal gutless.

I did a distance run the once we were both in the car, it never seamed to pull strong over about 70, the car is fitted with original car mats and it just felt to drive as if it was not getting full throttle, as I was coming down the M5 I pulled the mat back put my foot down, it belched out smoke for a shrt while and realy pulled strong. Does not smoke after that and now pulls realy well.

All this because of an original Citroen mat in the correct place ( as they are fitted mats ) stoping me get full throttle.

Now thinking about this the car probably been driven all its life on about half throttle.

Would be nice to hear anyone else who have expereanced this.

XantiaMan · Post by **XantiaMan** » 17 Feb 2008, 13:52

It's definatly worthwhile checking all the pipes are intact, the boost pipe to injection pump causes a massive drop in performance when its split, not enough fuel to match the air, and because of this, boost is lower too!

There are simple tweaks you can carry out to the pump to improve overall performance, and still get good mpg. My tweaked Xantia goes like stink, and got 49mpg on Friday, which is great for an old school idi engine running more fuel, more boost and an SVO mix!

A very easy thing to do is remove the throttle damper and make sure the cable is nice and tight to reduce slack, i always notice a difference when this is carried out.

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