C5 2.0i cold start problem

viorelovidiu · Post by **viorelovidiu** » 21 Feb 2011, 10:51

I`m desperated looking for a solution!

Simptoms:
In cold wheater especially bellow 0 degrees engine starts normally and after one minute it becomes rattley and the revs are jumping between 500rpms and 1200rpm for about 2-3 minutes, after that is working normally and I could go to my workplace. If engine is warm, it`s start perfectly and no problem whatsoever. I dont feel any power loss, only the fuel consumption is very high and also an error came up on screen : Depollution system faulty.
p0170 permanent fault, richness regulation coherence si p0172 temporary fault, richness regulation maximum value. Lexia test. And Missfire erors on all injectors.

http://postimage.org/image/ogyj3w84/
http://postimage.org/image/oh559a78/
http://postimage.org/image/oha3vbok/

a video captured from lexia reader software after engine has started.

it must be a vacuum valve.. sometimes I find oil leaking on top engine cover and filter case...

I appreciate any help in this!
thanks!

PS: I work as IT Specialist at a BMW Dealer but I drive a C5

viorelovidiu · Post by **viorelovidiu** » 25 Feb 2011, 06:44

I`ve bought Lexia 3 interface because no one in citroen services doesn`t know how to solve my problem and the say it`s a common problem with this type of engine (EW10A) even on Peugeot Cars. BUT last winter with temperatures much lower i have had not any problems!

I`ve replaced MAP sensor and the problem still occurs.

This morning at -5 degrees Celsius I started the engine and after 40-60 seconds starts to rattle slow to 1000rpm, accellerating to 1200, revving down to 800rpm and again accelerating to 1200rpm, revving down to 500rpm and so on.
I started engine for 2nd time and I left garage and after 40-50seconds became to rattle again, trying to accelerate = no response; I`ve pushed pedal to the floor and finally getting a response and wheels slipping on the road.

I want to watch live data parameters in lexia3, may I know what I`m supposed to follow to indentify the problem?

Thanks in advance!

viorelovidiu · Post by **viorelovidiu** » 03 Apr 2011, 22:05

problem solved. it was lambda sensor (upstream oxigen sensor).
now it`s working like a charm.