Peugeot 406 2.1TD Accelerator problem? - gsb

When lifting off pedal to decelerate revs do not drop immediately, almost like being on a cruise control for a few moments. More noticible when lifting off from higher speeds.
A local mechanic says it could be a faulty Exhaust gas recirculation valve. (expensive to replace he assures me)He says that it can be disconnected and blocked off with no ill effect and it could cure problem. Surely all these 'Bits' are there for a purpose.

Any ideas appreciated

Many thanks
Peugeot 406 2.1TD Accelerator problem? - Davy_S {P}
Hi gsb,

I have a similar problem sometimes and I think mine is due to the accelerator cable not returning to rest quick enough, mine is getting frayed.

Is the pedal stiff to push if so this was covered here:-

Hope this helps.

Davy S.

Oops, where did that screw go!!
Peugeot 406 2.1TD Accelerator problem? - dieselhead
Not sure about 2.1 TD's but on 1.9's EGR can be disconnected by plugging the vacuum pipe from the vacuum pump to EGR solenoid. Should make the engine run smoother and give a couple more MPG. It's only purpose is to reduce oxides of nitrogen from the exhaust gases.

I think a damper is fitted to the throttle control on these engines (another anti-pollution device) to prevent it being closed too quickly. Should be adjustable.
Peugeot 406 2.1TD Accelerator problem? - gsb
Thanks for ideas both.


If disconnecting EGR does not effect emmissions re MOT, it sounds a good idea anyway unless you know of any other effects that it may have. Thanks
Peugeot 406 2.1TD Accelerator problem? - dieselhead
Disabling EGR is likely to be beneficial in terms of passing the MOT (it reduces smoke opacity) and engine wear is reduced as less soot contaminates the oil from the recyled exhaust gas.
The negative effect if your concerned with environmental matters is to increase NOx emissions which causes ozone formation.
Peugeot 406 2.1TD Accelerator problem? - cholin
I have this problem with my 2.1TD. It is usually a prelude to wildly erratic rev fluctuations. Mostly when idling but occasionally when driving which can be a bit hairy in traffic. I did raise the rev issue on the forum but it seemed a mystery. It happens so intermittently now (It has got less often over a year) that I live with it. But as it is intermittent I wonder if it is other than a mechanical fault. It went in for a check a couple of times to a Pug dealer and a variety of reasons were given for the problem (faulty ECU, the fitting of a new cat etc.) but they didn't cure it.
Peugeot 406 2.1TD Accelerator problem? - dieselhead
Could be caused by the a tired turbo leaking oil on the inlet side which the engine burns causing the power surging. Might only happen when the oil is very hot and thin. I guess you could check for excess oil residue inside the induction pipework. Air leaks at the filter housing also cause engine surging. Just a thought anyway.
Peugeot 406 2.1TD Accelerator problem? - gsb
Hi cholin. back in march I was having all sorts of problems and had to have (was told by a couple of injection specialists, hope I wasn't stitched up) a replacement fuel pump (ouch!! very expensive.) This did cure problems.
Previously 18mths approx had one of the many (i think it was called a) thermister valve replaced by my pug garage to cure the problem of a slight increase in revs when depressing clutch to change gear.

I gave up with pug garages and eventually found a local Delphi agent who seemed to know what he was talking about.
The lucas fuel injection on the 2.1 TD is now all looked after by Delphi
Peugeot 406 2.1TD Accelerator problem? - gsb
HI dieselhead

Have disabled EGR but problem not gone away. Back to garage again.

Peugeot 406 2.1TD Accelerator problem? - 9000
Had this on my xantia 1.9td- not sure if it's relevant to the 2.1 tho. It turned out that there's a small gas strut on the fuel pump which is compressed under acceleration- on return to idle it expands. My strut had failed and produced the symptoms you describe. Citroen wanted £120 for a replacement however on examining the design it was apparent that the strut was not really needed so I removed it and the problem was cured.
Peugeot 406 2.1TD Accelerator problem? - dieselhead
Should have pointed out that if the EGR valve fails in the open position, disconnecting the vac will have no effect. To check if it's not stuck open ensure the EGR pipe doesn't get hot when the engine is started from cold with EGR disconnected. Should stay cool for 5 mins or so.
I doubt that's the problem far more likely to be the damping arrangement on the throttle as 9000 describes - either a gas strut and dashpot arrangement or a combination of the two - check that the throttle closes reasonably quickly. If it was my car i would remove them temporarily to see if it made any difference....
Air leaks into the fuel from fuel filter area also cause surging problems so check for air in the clear plastic fuel lines if fitted. Worn piston rings (Engine burning blow by gases) or failed turbo oil seals could also be the cause but unlikely.
Peugeot 406 2.1TD Accelerator problem? - dieselhead
Should point out that a small bore rubber pipe from the vacuum pump to a solenoid operates the EGR. The other is to the brake servo - if this is disconnected it will affect the brakes. If in any doubt leave well alone.
Peugeot 406 2.1TD Accelerator problem? - dieselhead
On another safety issue.. removing the gas strut on the pump might not be a good idea - obviously the consequences of a throttle sticking in the open position could be very serious.
Peugeot 406 2.1TD Accelerator problem? - 9000
It's probably a good idea to replace it though I never bothered and suffered no adverse effects. I think Eurocarparts do them for about £60 and they take 2 mins to fit.

Peugeot 406 2.1TD Accelerator problem? - phoenix_sound

I have a peugeot 406 2.1 TD

The engine starts but there is no accleration,

Any ideas?

Peugeot 406 2.1TD Accelerator problem? - jc2
Some Fords had the gas strut on thee pump to stop the throttle snapping shut when you took your foot off the accelerator but it was done away with on later models and could be removed with no problems on earlier ones.

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