406oc.co.uk

Hi guys

I live near Stoke.

I've had XUD 1.9 diesels before ... BX 19, Xantia 1.9 TD. Also recently had a couple of 1.8TD Mondeos and very recently a M reg 300tdi Disco.

My Disco has just died so I wanted to get a 1.9 XUD estate with a tow bar and the Bosch VE pump.

When I got my Disco it was very slow an low powered. I turned up the hex bolt on top of the diaphragm on the Bosch and it was greatly improved. I turned it clockwise 3/4 turn ( 270 degrees ).

So I found this 406 1.9 l dt estate. 192k miles. Needed a car desperately so bought it. I took it on a test run but traffic meant we only tootled around town. So I bought it.

It starts well and drives great at low revs and below 40mph. Seems to have good torque at low revs pulling up banks etc. #

However ...

... at higher revs and over40mph there is no power ... no boost. Just seems as if there is no turbo on the car.

My Xantia had the same engine and pump I believe and that took off at about 2 - 2.5k revs. You felt the turbo kick in and you got a felt thrust. I went to Inverness a numberof times in that Xantia and it would sit at 100mph all day ... probably do 110+. I never touched under the bonnet on the Xantia ... never had to.

I drove this 406 on the Motorway on the way home and on a couple of occasions I wentto overtake ... looked in mirror, indicated, pulled over and put foot down and .... not a lot ... acceleration from 60mph was virtually non existant. It slooooowly crawled up to about 70mph. Pretty scary when cars in outside lane are racing up to your back end. Max it went to as about 75mph but that took a week.

I'm no mechanic. I've checked for obvious splits all over intercooler pipes. Checked boost pipe as far as I could trace it. Couldn't get near turbo as I presume it's tucked down the back of engine. I tweaked that hex bolt down 3/4 a turn on the Bosch like I did on the LR but no noticable difference.

On heavy acceleration there is no noticable black smoke, even when climbing under load so maybe just not enough fuel being supplied? I know about turning the max fuel screw in and taking the diaphragm off and turning starwheel etc so that the angle of the shaft is increased ( = more movement of pin ) on pump ... but haven't done that yet.

I'd like to get at turbo to see if fans are ok and check play.

The otherthing thatseems weird to me ... accelerator cable. There seems little movement on pedal before I'm hitting floor stop. I seem to have to be hitting pedal on floor through all gears to get any acceleration. If you manually rev car under bonnet with leveron pump ... you move lever about an inch before there is any response?

Does cable need setting up?

What do you think? Am I expecting too much from a 192k miles car?

Anything else you can think of?

MAF sensor? EGR block? Cat blocked?

Oh I've changed fuel and air filters.

Thanks

your not expecting too much i dont think. my 1.9 xud has 164k on the clock and it pulls very well.

follow the cable back from the pump and you will come to the adjuster were there is a clip. get hold of the black plastic bit that the clip is on and slowly pull it away if it comes away and the pump doesnt move then put the clip in the new place. keep pulling it away from the pump untill it goes tight and the pump moves

this adjusts the cable so there is no slack on it ..

Cheers Gary

I looked at that black tubing/clip you talk about. There is no slack in the cable and only about half an inch of that tubing left through the bracket so not a lot to play with.

I took it for a run this afternoon down a stretch of dual carriageway. Slight incline. Absolutely flat out down the bank 85mph. Up the incline 75mph ... and it took forever to finally get to those speeds.

Can't be right?

it doesnt sound right no ...
mine gets to those speeds very easy really. no hanging about .
can you hear the turbo spooling ?
maybe try some injector cleaner in the fuel

You said you turned the torx screw on top of the pump in? You're supposed to screw it out, you're limiting the travel of the pin if you screw it down.

Got a boost gauge you can chuck in the loop to check the pressure?

Air filter, fuel filter, tank strainer? Blockage on any of them will destroy the performance.

Gary ... I can't hear turbo kick in at all and I certainly can't feel it.

Stevie

I'll check my old notes re the torx bolt. I thought you screwed it in ( down/clockwise ) to put more pressure on the diaphragm to increase boost? That's what I did with the Land Rover ... the Landy guys call it the smoke screw as the more you screw it in the more unburned diesel and black smoke you should get?

I don't have a boost gauge. I should get one so I can see what pressure I'm getting.

The car NEVER black smokes ... so seems as if never getting too much fuel.

The easiest thing is for me to turn the pump right up and try and adjust the throttle so I know I'm getting enough juice.

Next is to check the boost feed to the turbo and make sure there are no tears etc. Check turbo for wear etc. Can I get at turbo from underneath or is it a manifold off from the top job?

Intercooler off and flush?

Cat removal?

you will only get the turbo from underneith the car .

Skires wrote: Stevie

I'll check my old notes re the torx bolt. I thought you screwed it in ( down/clockwise ) to put more pressure on the diaphragm to increase boost? That's what I did with the Land Rover ... the Landy guys call it the smoke screw as the more you screw it in the more unburned diesel and black smoke you should get?

Think about it, the fuel needle is lifted by the turbo vacuum, letting more fuel be added. The higher the pin goes, the more fuel is added, more fuel = more performance.

The torx bolt at the top of the pump controls the maximum travel of the fuel needle, if you push the "stop" in, the needle can't rise so much meaning less on-boost fuel, less fuel = .......

;)

I've re read some of my favourites ... that outside top torx is non boost ... so is for low end power on take off etc. There is no problem with that so no point me messing with that.

Re the pump it's the max fuel and the diaphragm unit turning ( to enable pin to come out more ) that I need to look at.

I can always put them back to normal if it achieves nothing and then look at turbo.

I've been out and had a good look.

Pipe from space ship on top of Bosch .... one end where it attached to intercooler pipe ( to turbo ) had a small split in it ... didn't seem to go all the way through but I cut it just past that split and re attached and did jubilee up tight. At the other end where it attaches to space ship the clip was useless ... just waggling around doing nothing ... so I fitted a new jubilee clip at that end.

I also adjusted the throttle cable to take up slack.

Took it for a run. Only went a mile but the acceleration ( especially past 40mph on the flat ) seemed much better. I came home via a very steep bank ( we live on top of a big hill ). Previously it came up that bank for 85% of the bank in 2nd and just hit 3rd at the top with foot to the floor ... probably just hit 40mph. It's just flew up there and I had to put it in 4th 3/4 way up and at 50mph I had to slow down.

That seems like the Xantia. Seems pokier at higher revs.

I also like the fact that I'm now getting a whiff of black smoke on hard acceleration under load but no black smoke under normal driving ... so again it looks as if the fuelling is better.

I've not tried it yet on a faster road to check top end speed but it does feel better.

Listen ... I'm not a boy racer ... I'm 50 and I usually drive like a pussy ... I just want the right power for safely pulling out at junctions and overtaking on dual carriageways/motorways.

Hopefully it's looking good. Quite pleased if that's all it was. Didn't want a roller ... just a cheapy that will keep the fuel costs down.

By the way ... I can't see the max fuel adjuster on this Bosch pump?

It's under the immobiliser cover, ballache to get to on these, i'll dig out the pics i did.

copy/pasta from other forum i put this on, dunno if i posted it here.

This is what the fuel screw from the 406 looks like if you take it out the right way...

This is what it looks like if you take it out the wrong way...


From the start, this is the Bosch semi-ecu pump from the 406. The arrow points to my enemy, more about him later.


To get the cover off, remove the bolts/screw/threaded things circled, the ones in green won't be visable from the normal working angle and you'll need to hang right over the engine or use the force to remove them (unless you've got the pump in a vice, then it's a piece of piss)
To get the snap-off bolts out, use a chisel or other sharp point and strike against the tapper to push the bolt anti-clockwise, once they're free you can take them out with your fingers.



That brings us to here.


Then remove the arm running down the right handside / back of the pump.


Then the fuel return fitting, it's a bloody great thing on the 406, large allen key to remove the end, then deep 17mm socket to remove the fitting, not forgetting to drop the copper washers in the process.


Now we get to kill the roll pin, ******* thing. Stick the grinder in and make access to the pin, then drift it out towards the back of the pump.


The roll pin fits into the valley of the fuel screw and provides one final piece of security, it is supposed to be an immobiliser after all ...


This is one time when the usual "apply 2 coats of violence" won't work, it's quite a thick casting.


When you've got things stripped off, it might be worth freeing up the throttle stop on the back of the pump, nothing worse than getting it all back together, tweaking the fueling and having it tickover at 1,200rpm and finding you can't get to the ****ing throttle stop! :mad:

Stevie

Thank you so much for taking the time to post that.

What a game though?

The pump on the Land Rover is a doddle.

I did mine on the car so just gopt a spare max fuel screw and snapped the old one off.
Absolute pig though! I also tired to advance the pump timing a little bit but the ECU had a fit!

The day after I bought it the car ran on for a few seconds on a couple of occasions ... not done it since.

Usually that's stop solenoid and an easy swap. Armour would have to come off to get at that. I called Diesel Bob who said they would get the casing off for 90 quid if I took the pump off. They also said it may not be the ss but the pump falling to bits inside and little bits of metal sticking the plunger? Oh great.

Once the armour is off can you leave it off and do away with the immobiliser side? Fit a normal ss and get 12v on it when key is on?

Talking of which ... if I have to remove battery ... what will happen re immobiliser when battery re-connected? I have just 1 key ... no remote c/l ... just locks/opens when opening door. No keycode pad.