Needing some advice on some 2004 325i issues..

[Nbaillie]

Hey all, first time poster as I didn’t know where else to turn to without taking it to the dealership. I don’t know very much about cars but am trying to learn. This car probably was not the best car to start with but here we are. I’ll do my best to explain the issues happening and answer the best I can, I have an OBD that can connect to my phone that I can screenshot for any possible info that it can provide somebody.. my boyfriend is about ready to blow it up, but I really love my car and I’m hoping to save her 😞 thanks in advance! 
 

End of may of this year (2023) my boyfriend bought this 2004 BMW x3 2.5i .  Unsure of how many km it had.. but it now has 405,774km for reference. One crappy day in the middle of June, boyfriend was on the highway, going about 110 km/h when the rad hose blew off. I’m sorry I don’t remember exactly what it’s called but it was spraying coolant everywhere and the car  obviously overheated. This was the beginning of a STEEP uphill battle, a lot of the cooling system has been replaced. Sorry in advance if I mess up the names of anything I’m tryin haha. These are the things that were replaced regarding this issue. The car was pretty much rendered undrivable in this time. ( about a month)   Both hoses top and bottom, the rad itself, a sensor.. (perhaps it was the coolant temp sensor), rad fan, resivior tank and the water pump.
Finally, the car ran again without overheating. Was running okay until mid July when I was about 3 hours a way in a tiny town with no McDonald’s let alone bmw parts. Hit a decent bump, lit up like a tree then died. Would click but not turn over. It sat in this town about two weeks before it was discovered that the o2 sensor was either unplugged or was burnt out. (Can confirm once bf is awake) the car was driven back and was running rough.. but ok. Oops.. sorry I forgot to mention that we bought the car with catalytic problems. I don’t remember exactly but I’ll insert the codes I got when I first plugged in this obd on Aug 31 

P0430,P0444,P2098

On September 22 i was getting up to speed on the highway 110-120 km/hr and the car went BANG then lost all power. Thankfully I was next to an off ramp and got to a adjacent lot. this is the first time a car has ever done such a thing to me let alone while I was driving it was very frightening, however glad I experienced it and now know how to handle such a situation

P0305 P0040 P0306 P0304 P0300 P0301 P0303 P0302 and P16A7. 
these are the codes that came up once I got parked. Bf came and I believe spark plug 1 had come off… will confirm later. I had to go to a city 3 hours away that day and it did okay. 
 

ever since it’s been kinda running like !Removed!. The spark plugs and coils have been replaced, the upstream 02 both were replaced. However unfortunately the downstream ones haven’t been changed as bf is having a hard time figuring out how to get to them without “pinching the lines with the firewall” I believe he said. Any advice on that? 

forgot to mention that since the cooling system problem it kinda reeks like in my opinion burning coolant but bf doesn’t agree he said trans fluid or oil but to me it smells.. sweet? I dunno but after driving, long or short distance doesn’t really matter when you open the door or walk by the front of it you get punched in the face by the scent of burning car fluid of some sort. If that info helps at all. Presently the car is running like absolute poo. It has a really hard time in stop and go traffic, it like kicks back? If that makes sense.. when idling it like VIBRATES the car the rpm gauge was literally bouncing.. then after awhile of rumbling and making that noise ( I’ll insert an idle video if needed)  it will like even out and sound okay. Sometimes the car has like what I call turbo power it like has super extra power… in cruise control sometimes like it feels like it’s giving itself more gas then I’m giving it if that makes any sense I’m so sorry. But other times it’s got d*ck all for power like two days ago I’m talking pedal on the floor sitting about 4-5000rpm and going maybe 40ish km. Felt like it was gonna die on me. Almost like that 02 incident. Thankfully I got it home. Spark plug 1 was unplugged a bit again.. he put it back in and I believe he switched them round but not sure he said something about them being too long?  Or that we need new ones and they need to be gapped? Burnt coil? But today it ran like crap I didn’t think I was gonna get it home this time tbh. same problems as usual running super rough kicking back. I was accelerating from about 60km to 110 km and the rpm shot up to 6000 rpm then dropped. I let off the gas then gave more and it accelerated alright .. I put it in cruise control and it was going ok at a solid 120km for about 5 min then out of nowhere it dropped again. I did make it home but it was a rough ride.. if you made it this far, with my scrambled, half !Removed! knowledge wall of text, thank you from the bottom of my heart for reading this mess and thank you in advance for your reply.. I’ll find out any missing info if needed as I’m writing this in the early morning and I can’t sleep as I’m worried about the future of my car 😞 thanks so much! 
 

- A girl just trying to save her bimmer 😞 
 

 

 

 

 

 

 

 

[Greydog]

Hi Naomi

First after the engine bay got its hot shower a lot of Electrical connectors got flooded so a careful check through them with a can of good electrical contact cleaner would be my starting point. 

 P0430 Cat needs attention  At your mileage they could need replacing ,P0444,Evap/Purge control check and change the Vacuum lines Evap unit  P2098 O2 Sensors If you and your BF are not aware take a look at www.realoem.com it is an online BMW parts list put your Vin into the search box it will bring up your Model then search the sections for what you need. Another good source of information is www.pelicanparts.com check their BMW Articles section lots of "How To's" with pictures.

P0305 Mis Fire Cylinder 5 P0040 O2 Sensor Circuit P0306 Mis fire cylinder 6 P0304 Mis fire Cylinder 4 P0300 P0301 P0303 P0302 and P16A7. Just about all your codes are Mis fire related 

These would be electrical faults so check the looms to Injectors and Coil packs 

There is a BMW Diagnostic Program "BMW 1.4.0" not expensive around £20 if you get it loaded on to a laptop it will give you Dealer Level access for fault finding programming and generally fixing stuff

My personal course of action would be to carry out a compression test that will let you know that the mis fire issues are Ignition/Fuel related not mechanical (Burnt exhaust valve) 

Next the cats and the O2 sensors get them changed if all the Vacuum lines are OK and the Evap is OK refit the plugs coils packs and injector wiring and it should be good to go

Good Luck 

Dave

[Nbaillie]

Thank you so much for your advice i really appreciate your insight I’ll send this to him and report back the findings. You’re amazing thanks again!