Today I started my e46 330 and had a coolant light on. Noticed the ET was almost empty. So topped it off. I think i have a leak somewhere. Everything has been replaced in the cooling system in the last 25k. But then left and drove to the end of my street and it began acting up with an idle issue. It'll misfire here and there then shudder momentarily. No CEL. I dont think these two are even possibly related...just coincidental? Once i'm moving it seems to run ok. Also noticed as of late that the accelerationfeels pretty sluggish. My gas mileage hasn't changed. So did tons of searching and found tons of information on the bazillion things that can cause this...one of which was the possibility of a soft fuel pump failure. It happened with about a 1/4 tank of fuel...but i havent filled the tank yet to see if it goes away with more fuel. Just parked it in the garage and took my other car. So I ordered one just for preventative maintenance since they aren't to expensive. I need to check the lower intake boot for cracks yet, already replaced the upper one. I also plan to check the vacuum system. Vanos hasnt been done yet either (i'm at 105k and its not making noise, so didnt want to touch it). Fuel filter is new in the last 20k. I'll keep you posted, but anything else I should look at that I over looked?
Sounds like your looking in the right areas for the misfire. Another place I would look into is the coils themselves failing. I don't think your cooling system issue is related. Put it might not be a bad idea to pressure check the cooling system to see if it is leaking.
Ah yes I meant to mention that the coils were replaced at 61k. so a little over 40k ago. Would that be typical? Some one also said that it may possibly even be the head gasket, but i'm thinking i would have alot more issues than random misfiring. That car has always been babied...owned by "grandma" if you will till I bought it, and ive taken it up to maybe 5k rpms twice. As far as the cooling system, I did drain it to do the water pump 2 months ago. So maybe i did something wrong in the bleeding process (was my first time doing it) that may have prematurely hurt something. I would think it would blow sooner though if that were the case. Lately we have had super hot days in ohio where ive sat in traffic, A/C on, pushing these systems to the max.
So I was just thinking...i think i goofed on the cooling system flush. I kinda topped it off and really didnt leave room for air...maybe she blew due to that?
Cooling system is not suppose to have any air in the system, did you bleed the system after the flush?
The cooling system is designed not to be over-pressurized, the so-called 'radiator' cap (reservoir/expansion tank cap), if it's working properly, will maintain a specified pressure for the cooling system. If the system is over-filled, excess should just drain off. Coolant expands when hot, if your coolant system can't accommodate this thermal expansion, you'd see fairly extreme consequences in very short order - blown gaskets or hoses, for instance. Since it's been a couple of months, I'd think it's unlikely any over-filling would be a base cause of any coolant leak. It's best to keep your coolant at it's max hot/cold levels without being over-filled, but over-filling normally shouldn't cause disaster. The reservoir/expansion tank is meant to have some air-space at the top of the reservoir, which doesn't affect the rest of the system, as the expansion tanks are typically placed as the highest point in the cooling system. What bleeding procedure did you follow, and what part do you think you may have done incorrectly?
Hmm I followed this DIY by BavAuto and compared to a couple DIY's, of which are all pretty much the same. Here's on I found on e46fanatics. http://www.e46fanatics.com/forum/showthread.php?t=689618 http://www.youtube.com/watch?v=mcYjGHU4lEY
If you went through the filling, bleed, refill, bleed, & repeat process until you had no air coming out the bleeder, that ought to have done it, presumably!
So i reviewed the flushing DIY and one thing i think i overlooked was turning the heat on high when doing the fill. Im pretty sure it was all the way cold when i filled. Just got in from looking at it. No leaks at all anywhere in the system. Turned on the heat, filled the ET, rechecked the purge and drove it around the neighborhood for a bit. lots of start stop. The engine never misfired or acted up either. I'm waiting for the car to cool a bit before i pop the cap to see how the level is and to recheck for leaks!
I'm in Cleveland! So checked the car after a couple hours and the level was still indicating full. There was some coolant on the ground but I think it was from when I had spilled some earlier.
Howdy neighbor! Not having your heating controls on to let coolant circulate into the heater core certainly could be why your level was down. Either pressure check it to confirm any leaks, or keep an eye on it and if it's down again later, then do a pressure test. Sounds like your running issue may be the bigger problem to resolve but I don't have suggestions for that offhand - check what Charlson suggests and go from there!
Thanks! I appreciate the help! The new fuel pump shipped today, so should have it mid week. I'm just going to drive the car to work and stuff this next week and monitor the cooling system since its all local driving....if she blows, i wont be to inconvenienced ha
Alright some pics for you. To clarify, this is full on the coolant ET (cold). I am correct to assume that when cold, it shouldnt be full to the top?
If the owner's manual I found online for a 2004 330ci is the same as yours, it says the fill range is between the two red balls molded into the stick, with the top edge of your filler neck as the measuring point. If the lower ball is even with the top of the filler neck, it's full up. Hot, you don't want it over that point for sure (usual caveats apply for checking a hot, pressurized cooling system - carelessly popping off the cap when hot can result in hot coolant spraying and getting burned, including the face). When cold, you'll want at least the top ball even with the top of the filler neck.
Thats what I figured...I checked this morning and no leaks or drips on the cardboard under the car. Level was still indicating full. So drove it to work without incident. I'm just going to monitor it throughout the day. Also, is it normal to hear the whirring/whining of the fuel pump? It seems fairly noticeable if your by the passenger rear wheel. I uploaded a recording. You can hear it amidst the engine/exhaust. If you're not supposed to, maybe thats another indication the FP is going... https://www.youtube.com/watch?v=S2iM2SiCRN8&feature=c4-overview&list=UU3jf-xKCw92rqM8cIAO4NDw
UPDATE - So the coolant leak was actually present, just very slow. I noticed leaking fluid this afternoon, so looked harder and it was the radiator! So I am picking a new one up tomorrow along with a new auto trans temp sender since that guy broke, and a lower coolant tube. I inspected everything else in the system carefully, (ET, upper hose, thermostat/housing, auto trans cooler) and looks good. With all that replaced, the cooling system will be 100% refreshed. AKA peace of mind! Also replaced the fuel pump and that is working and good now. Obviously wont know if that fixed the misfire issue unless it never happens again.
Not having an E46, I can't say much about whether things are sounding normal there or not. You might want to scan to see if any codes have been thrown related to your misfire. Sounds like you're working through stuff, kudos for that! Best of luck with the rest of it!
Cooling system good! Took the car to my friend's shop and he has the same car, and we found out whats causing my random idle issues...CCV is sticking. Once I get the motivation to pull the intake on this thing i'll do it. Also the front crank and rear main seals are leaking...typical M54 stuff...so i'll have to deal with that at some point.
