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Matt, Mechanical Engineer
Category: Car
Satisfied Customers: 22736
Experience:  BEng hons Mech engineering, in auto industry 22 years
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i have a 2009 Peugeot407 1.6 hdi. When cold it fires up first

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i have a 2009 Peugeot407 1.6 hdi. When cold it fires up first time but splutters for about 5 seconds and is then ok. This doesn't happen except first start in morning and is driving perfectly. I had a similar experience with a citroen berlingo 1.6 hdi a few years ago but never bothered trying to sort it and eventually sold it as it was. What is causing this.

its worth considering fitting a new fuel filter as if only slightly blocked this can lower fuel supply pressure and choke the main pump, the pump will be more sensitive to this when its cold as diesel thickens considerably with low temperatures.

and if this is OK then also check the connections to the EGR valve, if either the vacuum pipe of electrical connection are damaged / corroded then the EGR can be on all time which certainly will hurt performance. Its also possible that its a fault with the EGR valve so its worth removing the valve and cleaning it out with brake cleaner, if it looks particularly clogged then replace it.
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