I have a problem with a horrible rattling noise on a 2000 model year 306 Meridian 2.0HDI. as far as I can tell it is being caused by the EGR valve. It sounds not dis-similar to petrol engine "pinking", but dissappears at 3100rpm and above (which I assume is when the ECU closes the EGR valve). The engine runs perfectly otherwise, and returns fabulous economy.
I have heard from a number of sources that rather than replacing the valve, it can simply be disconnected/removed/blanked off, without affecting the emissions dramatically.
Does anyone have any experience of this?
Thanks in advance.
David.
HDI EGR valve.
Moderator: RichardW
Yes....
Sympton
Between 2000 and 3000 rpm engine starts to rattle only on acceleration and only if warm (I wouldn't have bought the damn car if it had done it cold).
Dealer says it is EGR valve.
1st tried just disabling EGR (disconnect vacuum pipe from EGR valve and block off at control solenoid).
2nd totally removed EGR valve.
I did this by taking the valve off; I made a flat steel plate the same shape as the foot of the EGR valve and screwed it the exhaust manifold instead of the EGR valve (with a new gasket). Then I cut the inlet manifold end off of the valve, flattened the tube in a vice and rolled the end over (like the end of a toothpaste tube) and bolted that back onto the inlet manifold.
The engine still rattled.
3rd attempt: I changed the injectors. The rattle has gone. My wallet is empty.
Basically on a low accelerator position the common rail pressure is low and so the injectors don't leak. Also below 2000rpm the rail presssure stays low because the engine is turning slowly enough that the ECU can get all of the fuel in without needing a high pressure.
Above 2000rpm the engine is turning fast and so the injection window is small (the fuel has to get in before the piston has gone). The only way that the ECU can get the fuel in fast is to crank up the rail pressure.
Above 3100rpm the pre injection is switched off.
I suspect that the injectors are opening up for pre-injection but if the rail pressure is high then they fail to close again properly. The result is too much fuel going in before TDC which is why the noise sounds like pinking, it basically is pinking.
My injectors went at 125,000 miles.
You probably only have one bad injector, but find out which one is not too easy...
Sympton
Between 2000 and 3000 rpm engine starts to rattle only on acceleration and only if warm (I wouldn't have bought the damn car if it had done it cold).
Dealer says it is EGR valve.
1st tried just disabling EGR (disconnect vacuum pipe from EGR valve and block off at control solenoid).
2nd totally removed EGR valve.
I did this by taking the valve off; I made a flat steel plate the same shape as the foot of the EGR valve and screwed it the exhaust manifold instead of the EGR valve (with a new gasket). Then I cut the inlet manifold end off of the valve, flattened the tube in a vice and rolled the end over (like the end of a toothpaste tube) and bolted that back onto the inlet manifold.
The engine still rattled.
3rd attempt: I changed the injectors. The rattle has gone. My wallet is empty.
Basically on a low accelerator position the common rail pressure is low and so the injectors don't leak. Also below 2000rpm the rail presssure stays low because the engine is turning slowly enough that the ECU can get all of the fuel in without needing a high pressure.
Above 2000rpm the engine is turning fast and so the injection window is small (the fuel has to get in before the piston has gone). The only way that the ECU can get the fuel in fast is to crank up the rail pressure.
Above 3100rpm the pre injection is switched off.
I suspect that the injectors are opening up for pre-injection but if the rail pressure is high then they fail to close again properly. The result is too much fuel going in before TDC which is why the noise sounds like pinking, it basically is pinking.
My injectors went at 125,000 miles.
You probably only have one bad injector, but find out which one is not too easy...
You probably want to read this:-
http://www.christiantena.pwp.blueyonder ... index.html
http://www.christiantena.pwp.blueyonder ... index.html
Having heard this, I am now much more convinced that it is one or more icky injectors. I am also glad that all my engines are mechanical injection! Haynes still don't supply a manual for any HDI engine (although I no longer trust anything that haynes say) Did you do the job yourself christi? or was it a dealer who had the pleasure of emptying your wallet?
A dealer did it, but I had problems with the injectors he sold me and so had to change them again. That time I did it myself to keep costs done.
There is a Haynes manual for Peugeot 406 HDI.
You also need a new injector clamp nut each time and you need to use a torque wrench.
Also it works much better if you clean out the hole with a rag. Keep stuffing a rag down there till it comes out clean.
I didn't change the plastic sleeves; they are just a spacer or keep the dirt out or something, they don't really seal anything; that's what the copper washer is for.
I also fitted bigger injectors which is worth maybe 10bhp or something but cost me more.
You can get recon injectors for £75 but they only change the nozzle which is why I had trouble and had to swap out two again. In retrospect I would have fitted all new ones from Bosch.
I have a lead on getting these for little over half the cost of what they are in the UK but I haven't figured out whether there is a business in it for me...
There is a Haynes manual for Peugeot 406 HDI.
You also need a new injector clamp nut each time and you need to use a torque wrench.
Also it works much better if you clean out the hole with a rag. Keep stuffing a rag down there till it comes out clean.
I didn't change the plastic sleeves; they are just a spacer or keep the dirt out or something, they don't really seal anything; that's what the copper washer is for.
I also fitted bigger injectors which is worth maybe 10bhp or something but cost me more.
You can get recon injectors for £75 but they only change the nozzle which is why I had trouble and had to swap out two again. In retrospect I would have fitted all new ones from Bosch.
I have a lead on getting these for little over half the cost of what they are in the UK but I haven't figured out whether there is a business in it for me...
the plastic sleves help to keep the injector straight & sitting squarely so that the copper washer seals properly,for all they cost it would be a good idea to replace them,it saves doing the job twice. i dont see why you would need to replace the injector clamp nut ?? citroen & peugeot do also recommend replacing the injector pipes each time they are disturbed on HDi's but iv never had a problem when re-using them.