cold start misfire - last try

[besembo]

Hi everyone
want to describe my problem last time. Maybe someone can give me a useful advice.
m54b22 e46 2002
Have been fighting this problem for 7 months.
Symptoms : start the engine - 1100 rpms, it goes down to 900 rpms and starts shaking - it goes to 700 rpms and check engine light is on. It is throwing misfire on 2-4 cylinders with fuel cut off.
Job done :
1) tried 18 different spark plugs
2) bought new coils
3) cleaned injectors, tested for leaks, tested on them on pro machine, additionally used ,,xado'' cleaner in fuel tank
4) spark plugs, coils and injectors have been moved to different cylinders without any result
5) fuel pressure was always 3.5 bars but I changed pump ( had one in spare, known good without cold start misfire on previous car )
6) changed fuel filter - it was clugged but still, pressure was good
7) ccv
8) disa valve
9) one day I also tried this method - removed ccv and disa and started engine - no result. sealed disa hole and every ccv hole and let gases to got outside - just in case if my 2 ccv's did not work. Then I put everything back
10) I DON'T HAVE VACUUM LEAKS ! vacuum was tested with pro machine at least for 20 times in different holes - had some but all of them are repaired long time ago
11) My o2 sensors are working and don't tell me I need change them just in case - if you say so, you must learn more about how they work on cold start
12) tried 5 maf sensors. Now iIhave simens vdo with reading 11-12 kgph. 3.1-3.1 gs - and this reading is good
13) measured resistance on cold air intake sensor, compared it to 3 new ones and all of them had same resistance
14) changed cranckshaft position sensor ( i had one in spare )
15) with very complicated methods found out exhaust camshaft sensor was faulty changed it with febi bilstein brand and it works perfectly - it works , do not start talking about it - just accept it
16) fuel trims are + 1 - 1 and maf smoothly follows rpms
17) rechecked a lot of contacts and ground wires
18) tested voltage on injectors and coils
19) used oil addictive to make it thicker ( just tried ) , it's 5w-40 mobile super 3000
20) used different fuels and fuel stations
21) air filter
22) tested cold engine without serpentine/ac belts
23) updated DME/ECU 8 times , used different programs
24) tried another DME
25) have visited many ,,pro'' mechanics in my city - silence
26) compression is 12.5-13
27) valve cover gasket - VR
28) vanos seals
29) valve seals
30) used 3 times, different valve cleaners
31) battery voltage is good
32) alternator voltage is good
33) i did not change engine temperature sensor coz it matches exactly the reality
34) took out whole intake system just sealed everything back to exclude any cold air leak , changed all he cracked boots or old ones
35) i have been living with obd2 scanner fusion/torque , inpa and bmw scanner 1.4 nothing unusual, have send videos to different ppl, they could not find anything.
36) cleaned icv
37) cleaned throttle body

and finally ,,something'' - I want you to think about this carefully

for first time i have had ( always, even after moving and replacing injectors, sparks and coils ) misfire with fuel cut off on cylinders 1-5
then i got 10 lifters from junkyard
for 2 days i was cleaning them and testing for pressure those could hold about 50 kg without leaking 5w-30 oil
cylinder 3 lifter was not working but i never had misfire on 3 cylinder
so i put the best 24 in
called engine specialist to set up my timing , he did and left
after that i got misfire on cylinders 2-4
i took them out second time but they all were good so it took me next 2 days to test them and clean again
called specialist, he set my timing second time.
still misfire on 2-4 cylinders
2 lifters i noticed where squeezed more then others , they where pushed in farther then others, i don't remember witch cylinders

so after that i am always getting misfire codes on 2-4 cylinders.
ofc after deleting errors and resetting dme - no difference

only thing I have is
lifters/timing job and misfire on other cylinders - THINK ABOUT THIS PLZ
2 squeezed lifters unfortunately i remember it too late or i'm thinking about it too late

one more thing after discovering faulty camshaft sensor and replacing it if I unplug maf it warms up much better even without check engine light but still inpa cached those code time after time

[MarcoZandrini]

Have you smoke tested the intake manifold? Sounds like vacuum leaks.

[nonturbodan]

I think you can rule out lifters. Your compression looks good.

These cars will run great even with collapsed, noisy lifters. Never seen one misfiring due to obviously bad lifters.

[besembo]

MarcoZandrini

but where ? how ?
really i use pro tool for this. we have one at work. put manifold on sealant and that sealant is not good i know but it is 100% guarantee. used berner brend.
if you remember i mention earlier in different post i am thinking about vacuum leak from fuel filter hosing gasket... i know how it may sound but f.e. Audi/vw and skoda if i remember it right 2.0 tfsi engines suffer from vacuum leak from back cranckshaft seal. i know this for sure for all 300%.
injectors and vacuum distributor is also sealed. i used bigger sized rubbers there.
i did not have any obvious leaks but still took manifold out in a case if something could narrow in cold.

[besembo]

I think you can rule out lifters. Your compression looks good.

These cars will run great even with collapsed, noisy lifters. Never seen one misfiring due to obviously bad lifters.

Thats the biggest confusing thing. a lot of posts in russion , english or even georgian they say lifters solve the problems. on the other hand they set timings again and 3-4 mechanics told me like you, even with collapsed lifters these engines keep running without cold start problems.

[besembo]

is there a spot that can not be detected by smoke machine ?
tested it from intake, from brake booster line, from oil dipstic tube. did it many times (i do it once a week) ...
do you guys know any specific spot ?

[sundernaix]

If i were you i would use a 4chanel lab scope and scope out power and ref voltage to fuel and spark to see if your having vlt drops. It wouldnt hurt to labscope dme and see whats all going on on that side too. I had a nasty miss for almost a year turns out a small wire was shorting to dme relay causing my random miss.

[besembo]

If i were you i would use a 4chanel lab scope and scope out power and ref voltage to fuel and spark to see if your having vlt drops. It wouldnt hurt to labscope dme and see whats all going on on that side too. I had a nasty miss for almost a year turns out a small wire was shorting to dme relay causing my random miss.

hmmm... i doubt someone in my country has it or knows how to use it correctly
i can find someone to work on it with simple osciloscope will it do ?
was your problem at cold start ?

[sundernaix]

It may work im by no means an expert. My problem was random at cold and while running. Same 3 conditions but always random timing on which and when. Had a freind who knows alot more than me give me a hand to figure it out.

[besembo]

could you plz share this info to your friend ? if it wont trouble him.

[sundernaix]

could you plz share this info to your friend ? if it wont trouble him.

Already planned on it ill see him in a few hours and get back to you

[jclausen]

Since we're pulling our hair out about it how about, check for signal to the offending injectors and coils when it's happening and how about test the coolant for any presence of combustion gases

[nonturbodan]

is there a spot that can not be detected by smoke machine ?
tested it from intake, from brake booster line, from oil dipstic tube. did it many times (i do it once a week) ...
do you guys know any specific spot ?

If the brake booster itself is leaking the smoke would be inside the cabin, under the dash.

Have you tried removing the vacuum line from the booster and capping it off? This is easy to do and would allow you to see how it behaves without a potential leak from the booster.

[besembo]

Yas i have done it. also i capped fuel tank breather valve hose.

Today i was translating some german forums. many of them clam to fix the problem after changing lifters.

time after time i,m thinking about those 2 squeezed lifters with i have seen two times.
Maybe head was repaired and they just made valves higher during breaking in process ?

[besembo]

Did engine rebuild and it still does the same

[vilkas88]

Wow - lots of parts changed! Have you checked the fuel vent hose lines, that run from fuel filler neck and fuel expansion tank to the tank, under rear passenger seats? Those hoses do crack and create vacuum leak - far from engine bay. I saw once how chipmunk or some small animal took many small nuts on top of leveling sensor bay, perhaps from underneath the tank. It is possible they bit into some rubber hoses. I would also make a list of spec torque values, and tighten those areas, where rubber O rings seal the intake manifold: throttle, DISA, manifold gaskets to engine bay. Check/Tighten the spark plugs to 30 Nm.

[besembo]

Wow - lots of parts changed! Have you checked the fuel vent hose lines, that run from fuel filler neck and fuel expansion tank to the tank, under rear passenger seats? Those hoses do crack and create vacuum leak - far from engine bay. I saw once how chipmunk or some small animal took many small nuts on top of leveling sensor bay, perhaps from underneath the tank. It is possible they bit into some rubber hoses. I would also make a list of spec torque values, and tighten those areas, where rubber O rings seal the intake manifold: throttle, DISA, manifold gaskets to engine bay. Check/Tighten the spark plugs to 30 Nm.

Thanks mate...
who cares about parts. since last post i bought 2 cranckshaft position sensors. now i have 3 one os brain new oem. made my own tester.
last time mechanic said he will make my engine new again. i was going buy 2.5 but did jot find any good engine. they were all in oil inside combustion chamber. So he told me cats were the reason. i did not beleave him coz i have tested cats in 2 different ways. at last it was burning oil so i said lets do it.
1) cats where soft failed so i got rid of them
2) piston rings all where worn (at 117k.km.)
3) head was deformed at a very small numbers but gasket was alive
i thought definitly it would work like new
but no
installed eu2, disconnected read lambda sensors (o2)
nothing at all
now at least after 2000 km's my combustion chamber is so clean i thought it was water inside
no oil consumption at all.

AND now i can not even sell it ... too much money and energy will be waisted
I'm no a sofa guy, I do things but now out of ideas.
an yas i have tested that hose, even with vacuum divice and rechecked everything after .engine rebuild, it was connected very bad i made evrything like it should be. The deal is i had much worse vacuum leaks on previous cars and did not have this simptom.


ahhh
now it detects misfire on 3 cylinder and sometimes 5.
of i hold rpm,s at 1500 no missfire at all but now its summer

[besembo]

as for disa and other parts they are all dead tighten and used bigger sized o rings everywhere , even at injectors. in a case leaks could appeir when its cold and smoke test does not show it and yas long time ago i tested evaporate system by 100% including valve test.

[besembo]

they are like
-,,dude use njk spark plugs, others do not work on bmw's''
- ,,even if you changed ccv 2 times they both could be defective''
That's all bla bla bla
I can change ccv system with eyes closed already.
when i'm asking why all my sparks work great on my other car likr ccv valves get silence instead answer

[besembo]

guys could someone tell me the resistance of coil ground cable on the engine ? the one with 8mm nut.
I mean resistance of that wire in disconnected condition from the engine. 12_2002_bmw_525i_spark_plug_diy.jpg

Mine showing 0 connected (as it should be) and 19 disconnected. It has resistor inside for dme ,,back-connection'' or something.
Not my engine but will do

[nonturbodan]

235 ohms I believe. The DME uses that to monitor the ignition coils. If it is not functioning properly you should have numerous ignition activation faults. I had a short to ground, zero ohms, and the car ran great but it would not store adaptations and had ignition faults stored for all six cylinders.

[besembo]

235 ohms I believe. The DME uses that to monitor the ignition coils. If it is not functioning properly you should have numerous ignition activation faults. I had a short to ground, zero ohms, and the car ran great but it would not store adaptations and had ignition faults stored for all six cylinders.

Thank you.
Yas i found out it can be tested on coil middle pin connector.
Just check it in any case

[besembo]

And i tryed njk spar plugs, friend had them from perfectly working m54b30 - no difference.

[besembo]

Tested purge valve again. They say the correct way to test it was applying vacuum to it. It is 100% functional.
I started fantasizing...
I mentioned before, I have changed many maf's. One of them (oem) was getting low reading at high rpm's - strange it died in 8.000 km's. It began reading more 3.5gs (too much for 2.2) at idle and 32 gs at wot (tool low for anything), Or it could be damaged when they were ,,repairing'' the engine. Had another one, not oem but works perfect, installed it back - but it has nothing to do with my cold start, have been switching them many times back and forth.
Disconnected both pre-cat sensors and both vanos solenoids (I HAVE DONE THIS BEFORE 2 TIMES, BUT BACK THEN ENGINE WAS NOT REBUILD) , post-cats have been deactivated after engine rebuild and deleting catalysts.
Sprayed contact spray on oil sensors and inlet camshaft sensor again - just for fun. looked inside cam sensor connector with mirror, all 3 pins are in place.
Turned it on and no rough idle. Temperature was 35 degrees so i quickly turned it off to let it cool down some more.
fingers crossed

[besembo]

Nothing , still the same.