xsara picasso 2.0 HDi injector flow correction

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maxxo
Posts: 48
Joined: 21 Aug 2019, 01:00

xsara picasso 2.0 HDi injector flow correction

Post by maxxo »

in regards to my saga with the lumpy cold running

i've gone into the parameter measurements in lexia to check the injectors

injector 1: 1.22 mm3/stroke
injector 2: -4.75 mm3/stroke
injector 3 -1.69 mm3/stroke
injector 4: 4.98 mm3/stroke

plus additional information shown in attached images, curious as to why the EGR is doing something just after a cold start
only codes are the classic HDi glow plug relay
Attachments
131203648_156129922912014_7711103821312763972_n.jpg
131372689_220029189697004_1521787136678055578_n.jpg

petarc1971
Posts: 46
Joined: 01 Mar 2019, 20:50
x 7

Re: xsara picasso 2.0 HDi injector flow correction

Post by petarc1971 »

Flow correction is not good. According to the distribution of values, I would say that the problem is not in the injectors.Otherwise the injector parameters are read when the engine operating temperature is reached.

maxxo
Posts: 48
Joined: 21 Aug 2019, 01:00

Re: xsara picasso 2.0 HDi injector flow correction

Post by maxxo »

are we looking at more likely to be the fuel pump/fuel rail?

i'll be driving it about 100 miles tomorrow, so will re read them upon returning home to check how they look when hot

maxxo
Posts: 48
Joined: 21 Aug 2019, 01:00

Re: xsara picasso 2.0 HDi injector flow correction

Post by maxxo »

i also revved the engine up slightly at first to 1028 rpm from idle

these are the readings i got whilst conducting this
injector 1 flow correction: -0.20 mm3/stroke
injector 2 flow correction -3.57 mm3/stroke
injector 3 flow correction -1.29 mm3/stroke
injector 4 flow correction 5/06 mm3/stroke

1124 rpm (this is where it smoothens out most days after cold starting)

injector 1: -0.43 mm3/stroke
injector 2: -2.78 mm3/stroke
injector 3: -1.92 mm3/stroke
injector 4: 4.98 mm3/stroke

now, i'm aware from doing some research these results are not good at all

where is best to proceed with this? i absolutely thrashed the car today, but as per usual i do a lot of motorway driving so barely any smoke and didn't make any difference to the way it was running.

petarc1971
Posts: 46
Joined: 01 Mar 2019, 20:50
x 7

Re: xsara picasso 2.0 HDi injector flow correction

Post by petarc1971 »

Check-crankshaft pulley, pc belt tensioner, compression, injector washers.

maxxo
Posts: 48
Joined: 21 Aug 2019, 01:00

Re: xsara picasso 2.0 HDi injector flow correction

Post by maxxo »

Checked everything i can under the bonnet today, all looks absolutely fine, even charging spot on

warm idle
injector 1: 0.12 mm3/stroke
injector 2: -2.31 mm3/stroke
injector 3: -2.86 mm3/stroke
injector 4: 4.98 mm3/stroke

warm driving (1992 rpm)
injector 1: 1.22 mm3/stroke
injector 2: -1.22 mm3/stroke
injector 3: -0.67 mm3/stroke
injector 4: 0.59 mm3/stroke
now this seems absolutely spot on, however i have a feeling the flow correction doesn't kick in that hard whilst driving/revving

revved the engine up to 3k rpm whilst stopped, which made the readings somewhat behave

warm idle (just after static revving)
injector 1: 0.74 mm3/stroke
injector 2: -1.45 mm3/stroke
injector 3: -1.37 mm3/stroke
injector 4: 2.08 mm3/stroke

so, what i believe is causing the issue is failing fuel injectors on cylinders 2,3,4, injector 4 seems especially bad

smokes quite badly at cold idle, and runs lumpy when cold

petarc1971
Posts: 46
Joined: 01 Mar 2019, 20:50
x 7

Re: xsara picasso 2.0 HDi injector flow correction

Post by petarc1971 »

Now the values ​​are different, maybe you should measure the compression, do a test on the overflows or take the injectors for control.