Peugeot 405 SRi

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johnvvc
Posts: 2
Joined: 26 Oct 2001, 14:03

Peugeot 405 SRi

Post by johnvvc » 26 Oct 2001, 14:52

Hi,
I've had a 405 SRi for years and it's been generally reliable. However lately it has started 'playing up' - just as I was going to trade it for a newer car !!! The wife reckons the car knows and doesn't want to go !!!
The idling speed has become erratic, the car generally idles much too fast, whilst it's driveable it's obviously a nuisance in traffic.
I wonder if anyone has any ideas, hopefully as I'm disposing of the vehicle I don't wish to spend more than is necessary obviously.
(anybody want an above-average SRi with full service history + K&N + Haynes?))
I've disconected the battery and left it disconected for a while but that has not had any effect, there are no warning lights on the dash and all appears normal - apart from the high idle which incidentally sometimes tends to 'wander' up and down in speed.
Thanks for any help,
John
John

Dave Burns
Posts: 1916
Joined: 14 May 2001, 05:30
x 2

Post by Dave Burns » 26 Oct 2001, 23:43

Could be sucking air in somewhere, likely places are the vacuum pipe from the manifold to the brake servo and vacuum advance pipe to distributor.
Dave

johnvvc
Posts: 2
Joined: 26 Oct 2001, 14:03

Post by johnvvc » 28 Oct 2001, 16:35

Thanks for that information Dave.
Normally I would have automatically looked for leaks around the inlet side but the speed was varying so regularly between about 1000 and 2500 revs I thought it might have been linked with the ECU. I'm used to hunting caused by air leaks as being more random.
Anyway I had a good look yesterday. I removed the air-filter assembly and the rubber ducting between it and the inlet manifold to check for any leaks. I also removed the throttle potentiometer and checked it for continuity with a test meter. I couldn't check the actual resistance as I had no idea what to expect though it's operation did appear erratic. I'm not too sure how this operates - presumably it signals the throttle position to the ECU ? I squirted mild switch cleaner into the potentiometer via the hole which engages with the throttle valve spindle and refitted it after it had dried out. Operating it with a screwdriver it did feel a bit smoother in operation afterwards.
After reassemblying everything and making a slight adjustment to the slow-running the engine appears to be behaving. I also think that the slight misfire which I previously had at 2000 revs has gone (could that be down to the cleaning of the pot ?)
The car ran beautifully this morning so I think it's a case of 'suck it and see', I've still got some reservations but hopefully it's sorted.
Thanks again for your mail,
John
John