Peugeot 508 2.0 HDI rough start?

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stefan535
Posts: 11
Joined: 17 Aug 2023, 10:34
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Peugeot 508 2.0 HDI rough start?

Unread post by stefan535 »

Hi guys, I’m creating a new topic because I wasn’t able to find anything similar yet. So I had a problem with the wiring loom of my 2012 508 SW. It’s a 2.0 HDI 140, and since I got the Can bus problems sorted I found another problem.
Basically when starting cold it gives a bit of white smoke from the exhaust (2-3 seconds tops) that doesn’t smell too nice :lol: The engine runs a bit rough for a while, but when it gets warmer everything goes back to normal. Other than that I have no issues, it pulls like a train, gas mileage is fine, no warning lights or anything. The fuel filter is brand new OE, just like the air filter.
I tried checking the resistance of glow plugs in order to see if they work, they all are approx. 1.9-2.1 Ohms each. Could this be the g.p. relay? Should I be more concerned about the state of injectors? I had a Toyota avensis a while back and the faulty injectors were obvious - it ran like a tractor and smoked bad.
The other thing that interests me is there is no glow plug light on the dashboard. If I’m not mistaken it should come up every time I turn the ignition on, even for a split second (if it’s warm) and then go off - nothing like this happens.
Of course I plugged in my elm327 interface, but no trouble codes come up - no faults detected.
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moizeau
Donor 2024
Posts: 1847
Joined: 12 Jan 2015, 16:08
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Re: Peugeot 508 2.0 HDI rough start?

Unread post by moizeau »

Forget glow plugs unless you're -10 or more. I had white smoke in my van on a cold start, once warm, fine. It was the EGR. You need to get a full chip Diagbox reading really.
Pete
Notice the BX is still top the list but sadly gone
stefan535
Posts: 11
Joined: 17 Aug 2023, 10:34
x 1

Re: Peugeot 508 2.0 HDI rough start?

Unread post by stefan535 »

So a bit of an update, I got my hands on a better diagnostic computer and it seems like on idle it looses fuel pressure. To be exact when the engine is cold, and I rev it up a little bit, when getting to idle revvs it jitters because the fuel pressure drops. Will it be the fuel pressure valve? Seems like it. Is on the right hand side of the engine (looking from the bumper), under the intake and maf sensor?