floodys 4 1 Cars Posted October 7, 2008 ive got a 1999 306 hdi and when you boot it i get some black smoke, i know diesels smoke in general but i've a feeling that the egr valve has a problem, do's anyone know how to tell if a egr valve is broke or what the syptoms would be? the car seems to run fine and still good and fuel, its just this smoke that is a bit suspicious!! Share this post Link to post Share on other sites
Lan 24 1 Cars Posted October 7, 2008 ive got a 1999 306 hdi and when you boot it i get some black smoke, i know diesels smoke in general but i've a feeling that the egr valve has a problem, do's anyone know how to tell if a egr valve is broke or what the syptoms would be? the car seems to run fine and still good and fuel, its just this smoke that is a bit suspicious!! assuming its all running fine it sounds ok to me diesels are just smokey when booted period, you can always splash a bit of redex in there to help clean up the engine. Share this post Link to post Share on other sites
welshpug 1,627 Posted October 7, 2008 you could disconnect the EGR and try it. Share this post Link to post Share on other sites
RossD 43 Posted October 7, 2008 If the EGR had failed open, you would get absolutely no performance, the car would be a slug. If it fails closed, then you won't notice anything - In fact most HDi owners (Me included!) have intentionally disabled the EGR. Smoke on acceleration is perfectly normal on a TD, only start worrying if it turns white or fails the MOT. Share this post Link to post Share on other sites
floodys 4 1 Cars Posted October 7, 2008 i did read on TDOC which is a diesel website that people do disconnect the EGR, i noticed that when i had read it and went to do it to mine that the vac hose that connects to the valve had fallen off, i noticed that with it connected it seems quicker but little worse on fuel, one of the things that i asked on that site was if when the egr is disconnected and not plugged up can it break? i'm not sure on the operation of it etc!! also if when i did disconnect it, if i should have disconnected the multiplug off the other end of the vac hose!! cheers all Share this post Link to post Share on other sites
All Praise The GTI 3 Posted October 7, 2008 as a good friend of mine says: NO SMOKE NO POKE BABY!!! Share this post Link to post Share on other sites
Veero 1 Posted October 8, 2008 (edited) If the EGR had failed open, you would get absolutely no performance, the car would be a slug.If it fails closed, then you won't notice anything - In fact most HDi owners (Me included!) have intentionally disabled the EGR. Smoke on acceleration is perfectly normal on a TD, only start worrying if it turns white or fails the MOT. The people on the Pug 306 net forum harp on about it all day long (bless their little cotton socks). What benefits are there for disconnecting the EGR? Mine only smokes on a really heavy boot. I particularly enjoy covering people in soot if they've been tailgating. Edited October 8, 2008 by Veero Share this post Link to post Share on other sites
leon 1.9 0 Posted October 9, 2008 I've noticed it a few times recently but only if I'm going slowish and then gun it through to higher revs (usually as some fool has been stuck to my bumper). Pretty normal as long as its not smoking all the time (or white smoke, as said). I've had the EGR both connected and disconnected, the debate will likely never be settled, but theoretically with it disconnected you MIGHT get slightly more response and possibly a little extra acceleration, as supposedly the EGR returns exhaust gas to the inlet and thus reduces emmisions but also influences the air/fuel mixture. The easiest way is to just pull the blue multiplug off it (the ECU will register an error but shouldn't bring up the warning light). The inlets tend to get a lot of carbon deposits so disconnecting the EGR and giving it a bit of stick can help clear it a bit. Each car seems to be slightly different, some seem to use more fuel with it disconnected, some don't. Share this post Link to post Share on other sites
