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Quote:

Originally Posted by Rundtinden (Post 637059)

I will try to take a picture of the oxygensensor values and other interesting readings on the Bosch system.
A short summary: The car idles bad. Deviating with a hundred or so up and down from about 800 when cold. When hot the idle is from 1200-1400.
Have changed plugs, checked coils, cleaned maf, switched throttlebody with both sensors, replaced a broken rubber sleeve and checked multiple times for vaccum leaks in the engine compartement. Changed fuel filter and air filter, engine oil and filter.
Both old oilfilter and plugs looked in good condition.
Car still throwing random codes on misfire, on different cylinders each time.
It pulls strong when on heavy throttle, but misfires on light throttle and idle.
Next is AOS. Ordered today.
A thought came to my mind. After deleting codes and driving for 70km I hit the brakes hard to test them. The CEL immediately came on again. Could I have a vaccum leak in a brake booster hose or something? Just a thought.

Yes you could have an issue with the brake booster.
Clear the codes go out and do your brake test again see if it repeats.

You could hook up a vacuum gauge for a vacuum test then step on the brakes, that will tell 100% if there is a vacuum leak in the brake booster.
A vacuum test gauge only cost around $20.00

Changed the MAF for a new Bosch unit and replaced the AOS together with new piping.
Now I have changed MAF, AOS, new oil, filer, airfilter, plugs, fuel filter, inspected coils and checked several times for air leaks using start gas. Also cleaned throttle body and tried two different idle control valves and throttle position sensors. Same problem.
Today I changed the MAF disconnected the battery, reconnected after a few minutes. Ignition on for 60 sec, off 10 sec then started the engine. Idles up and down 100 rpm or so, can hear some misfires. Will hook it up, but suspect the codes are the same. Misfire on cyl 1, 2 and 3. Any ideas?
PS: When I changed the AOS I found a rubber hose hanging down next to the right wheel well. Is this end supposed to be loose?