Jnelson1182

so i have a 04 525i with just over 150k on the engine, i just changed out the plugs and disa within the last few weeks and within last few months ive changed ebox fan as well as thermostat and coolant tank and for the ost part it has taken care of all the issues i was having but i still have a slight rpm flucation when crusing at steady speed, and it feels almost like theres a dead spot in the throttle on acceleration as well as feeling really sluggish unless i press on pedal pretty far down. the other day i got 02 heating codes then cleared them and nothing until today which was an air mass code, cleared it and nothing else yet, im wondering if maybe this could be being cause by batt not being able to give car enought power on acceraltion, if thats poss or if maybe i need to clean my injectors? i was wondering what are some common signs of dirty injectors? Also since in planning on keep this car for awhile what are some things i can do and that should be done when it comes to PM since i got some extra money right now i would like to put it into making sure the car is good? i was thinking maybe doing all the hoses and things that are plastic that have been under heat stress for awhile now lol

donpb

Get a vacuum leak test done.

kd7iwp

This isn't the most relevant thing to you, but I have a 2001 325i with the same motor and I recently had the entire intake system out and replaced all rubber components (throttle body gasket, manifold gasket, o-rings on injectors, idle valve gasket, intake boots, CCV, dipstick o-rings, etc) and in the process I had my injectors ultrasonically cleaned figuring that with 212,000 kms it would be worthwhile. All of them were still perfect. The flow rates didn't change at all, one of them had a "Good" instead of "Excellent" spray pattern and it changed to "Excellent" afterwards. I'm glad I did it because I assumed they might be a bit gummed up after 20 years but it turns out it was completely unnecessary for me. I typically fill up at Chevron using 87 octane fuel.

scottalexander

I just changed my valve cover gasket and plastic valve cover (since I have the plastic valve cover version).

The car runs ultra smooth after the new valve cover.

This is due to the new PCV system embedded operating correctly inside the new plastic valve cover.

Jnelson1182

CAN I USE A Compression testing kit to test vaccum? if not can someone point me to guide on how to check compression while i have tool? also there this vaccum testing thing that looks like a gun.greesing gun kinda with gauge on it, can i use that or do i need some kind of smoke testing done?

seanjordan20

To test compression you just screw the hose into the spark plug tube and bump the key.

You need a smoke test to check for vacuum leaks. There's many ways to do it. You can get a cigar or by a make shift smoker. You can google how to do a smoke test and find a video on YouTube.

FormerE30Owner

You have Chevron in Abbotsford BC and you use 87 octane fuel?! I have done over 1 600 000 kms on 8 BMWs over 49 years and have had only one leaky injector. That was on my 1988 325is (M20) that had 666 000 kms. Bad injectors are rarely a problem in my experience.

Jnelson1182

what was signs/codes that leaky injectors showed? an ok i honestly dont think i have a compression problem as much as some kinda of vacc leak/ sensor problem, my readings from maf are crazy up and down almost constantly and super high when my issue happens. not sure if anyone knows this but on the new disa i installed i can close flap an cover tht lil hole n rather than sticking closed the flap will slowly open, is this ok or a sign it isnt holding vac? it does it really really slow if that makes difference. when it comes to compression what would be most noticeable symptom? on the intake elbow theres a smaller hose not the one to icv the longer skinnery one, that one along with the one heading towards brake fluid resivor are super super brittle as well as the hose coming off my check valve could these possibly cause my issue? i just wanna rule out everything before giving in to get batt since from what i can tell theres no issue with the output from the one installed tho from time to time i do get that pass airbag/restraint error. also could something with the pully belt system cause my acceration issue or woulld those issue be clear