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Lean Mean BMW 323 Ci

I consider myself a bit of a comedian really with that title.. Lean Mean...
It's forever running lean and its being a cu... mean about not letting me fix it

Anyway here's a thread for my rather pathetic almighty 15mph BMW

I've yet to add photos... some might have seen
 
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h701micra
Well a daily runner would've been nice but at the minute its just an expensive door stop/paper weight

No drifting, no skids at least not intentionally
Especially no welded diff

Closest is welded diff sub frame as they're prone for rotting and letting the diff fall out but that's about it
 
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h701micra
Here it is, my newly acquired BMW 323Ci

Its terrible. Yes I may have had it a day but that's my opinion on it. Its a terrible car at present



Lets pick some positives though rather than constantly beating it down

The interiior is great place to be, is comfortable the seating position is brilliant, looks alone its brilliant in there

Its a Coupe!! You cant beat a coupe version of the E46 they look fantastic.

It has a 6 cylinder engine. That famous BMW sound from their 6 cylinders is right there at the press of a pedal (or is it? more on that shortly)

Its holds the road really well. I'm a spirited driver. I'd say I push my cars harder than most people and that doesnt mean I thrash its back end off in a straight line, hard brake and snap the steering wheel for a corner, I'll leave that to the wanna-be's they have that area covered.

Apply some simple track time learnt experience to driving this car and without breaking the speed limit you can really enjoy the feel of the car. I often find myself unintentionally catching up others through carrying more speed in the corner (if I appear right behind you, I apologise). Now I've mentioned that for good reason. A well set up car must give the driver confidence in what it can do, and not have to fight it to get it to do what you want it to.

My Celica is a prime example of a great road holding car, it turned in brilliantly and held well although it was somewhat lacking. The Vauxhall Astra G we've got here too turns in very quickly. It does push on quite well also and although I know it will do what I ask its not the greatest confidence giver..

So onto the BMW.. its a different kind of ride, it will carry the same speed through the same corners but it requires less effort to do so. It drives really well

Other than the knocking at the rear, which could be anything at this moment in time as I havent inspected



 
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h701micra
So onwards with the BMW and giving half a chance to redeem itself

What's up with it that makes it terrible? Well in short the engine

BMW designed these engines to work with this and that with various gadgets to be more economical both in emissions and fuel and althering the torque curve for that extra grunt in the RPM range. Their designs and work were brilliant, and it must have cost loads to design all this because what was left of the budget went into the materials used to create it.. and there my friends is their downfall

Nearly everything plastic or rubber on these cars are prone to failure and being an engine, that's quite a lot of stuff to go wrong. The plastic becomes super brittle and the rubber hoses turn to play-doh and soon split. Heat fatigue and vibrations wrecks them.. great place for this material then in an engine bay

Now I'm going to pick at their design, the fuel pressure regulator's vacuum take off is linked to the CCV system (CrankCase Ventilation). Well it works don't get me wrong as its linked to manifold vacuum, but jeez making the CCV unit from plastic that's prone to cracking under heat stress and vibration.. in an engine bay.. time bomb waiting to happen. So you lose your crankccase separating ability and lose the vacuum to the fuel pressure regulator and of course a vacuum leak in the manifold. Brilliant.

Doesn't stop there either, they have a Secondary Air Pump system (Referred to as SAP) that the forums say pump fresh air to the exhaust to help warm the catalytic converters up faster. I call bully on that. I've inspected that system and in no form does it connect to the exhaust whatsoever. Theres only a vacuum line from the manifold to the EGR type looking valve. But i'll show that further as I've already removed it. I'm not going to say that's it they're all wrong, but from what I've seen (not tested) it doesnt apply

There's the DISA valve which is designed to change intake runner length to suit the RPM range for peak torque across the board. Except the flap that controls that dries, crack and falls into the engine, then the little pin it rotates on also falls off into the engine causing complete engine failure

The best piece by far is the inlet boot. The piece of rubber joining the MAF from the airbox to the throttle body.. that dries and cracks, causing yet more airflow leaks and fuelling issues. The idle control valve is separate from the throttle body, which is also prone to failure, that in turn complicates the inlet boots design further and that's where the crack most often, allowing yet more unmetered air in

I'll stop there, and I'll pass by each piece as I go through this. I'm sure the picture is pretty clear from now, everything on these is prone to failure, expensive to replace for the same results a few years on and everything one way or another causes some kind of lean running condition

 
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h701micra
Yesterday I returned the car back to having no inlet manifold. Suprisingly simple to do, only taking an hour to remove it I was quite pleased

From here, I'll modify, change or completely redesign if necessary my inlet system. I've seen the inlets available for £700.. no thank you. The BMW forums adopt a throw-away and replace everything attitude and never actually solve the problem, they just prolong it

Before removing the inlet manifold whilst under the bonnet I've removed whatever I deem unnecessary
The secondary air pump has gone... This entertained me, I've read all over the forums that this pumps air of sorts to the cat converters.. has anyone actually taken the thing off and inspected it on those forums? It does nothing of the sort from what I can see, it simply has a vacuum operated diverter valve, that diverts an exhaust gas to a pump unit on the left.. and then vents to atmosphere. Well mine's gone, unplugged and left. That leaves one less thing requiring a vacuum source so one less place to create a leak. The solenoid on the inlet is still in place and plugged in for now

EVAP Purge system, another piece of kit that can cause a vacuum leak, that also has gone, the valve remains in place and plugged in until I'm happy to remove completely and fit a 1k resistor in its place to keep the EML happy. The pipe from the inlet is now blocked up, and the pipe from the fuel tank is rerouted to a small hole in the airbox. This only does something when the car is sat and fuel has chance to evaporate, so it can happily evaporate into my airbox, if it condenses there's a drain hole. While the car is running the fuel wont evaporate per se and the airbox draw wont affect the fuel tank line.
I've tested this before I removed the inlet and its ran as badly as it did before, no tank pressure differential to note. So all seems well, very simple to do too

So far I've no removed the CCV, SAP and EVAP unit. Now I have 3 less places for vacuum leak

Future plans for the above
Create a small condenser tank like the oil one that'll catch fuel vapours and return them to the tank itself with a pressure relief valve

No plans for the SAP, it can stay removed and blanked off, one less thing to fail
 
I've just come from an e46 330i. I feel your pain. They are lovely cars to drive and be in but to own and work on? Nah. Try changing the headunit if you fancy no skin left on your hands. My 2000 reg BMW was more rusty when I got it than my 1993 reg k11 what does that tell you also. I also found whilst nice to drive and they do handle well and go quick, they are not very involved to drive and as such I have more fun in my k11 be it driving or working on it!


'94 k11 dot 1.0
McGill Motorsport steering wheel
Mountney steering wheel boss kit
Poorly fitted aftermarket backbox (3 inch rolled tip)
Lowered on Kilen springs
 

skymera

Brutal Honesty
E46 facelift is one of the best shape BMWs. The E92 M3 is my guilty pleasure even with its V8. Since then... I'm not sure, but I think the designers have had some sort of head injury.

I have one of those friends who goes through cars like I do underwear (Don't read too much into that) and they keep ending back in 46's, so I think that's a testament to how much fun they can be.

Subbing to this thread.
 
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h701micra
Its a massive pain in the arse of a car I have to admit, very disheartening.
I'll find out whats wrong with it eventually and it I cant solve it through adaptation of whats there. I'll start making parts for it and run it on my standalone ECU so I do as I please

Plenty of "Common" Problems to check out first though
I've no history of the VANOS system being done so that's on the list
New coolant sensor cant hurt for the few quid it is, especially while the manifold is off and its accessible
Cam and Crank sensor are again cheap to be had, even from BMW, so may be worth updating too

And the diff carrier is one to be looked at before going mad
 
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pollyp

Club Member
tday when I went to machine mart for some bits for my MIG, the Till guy used to work at the local BMW shop and he also talked about the silly DISA flap thing (their shop corner had loadsa expensive self destructed pistons from the failed parts getting sucked in). said can get these blanking plugs for the hole, keep the actuator plugged in to keep ECU happy and when removing the inlet mani, make sure you keep count of those orange washer seals and that it doesn't fall into the engine.
 
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h701micra
I've got a rebuilt DISA in this one (green ring seal) and it seems to be ok.

But to me if it's going to cause an issue like that later on.. why keep it?
 
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h701micra
Inlet manifold is still off. Haven't touched the car much

It's at this point I've had thought of breaking the car for parts, I've got friends with BMW's who could make good use of the parts and whats left I can make use of in another spaceframe build
BUT!
The finally thought always was that I wanted to at least enjoy the car before condemning it

While the manifold is off I've done the following
- Got a new coolant temp sensor, just because of its location
- Checked the knock sensors are tight
- Ordered a VANOS repair kit, no way I was paying BMW for a new unit destined failure with poor seals
- New Crank and Cam sensors to go
- New injector seals
- New vacuum log seals

There has also been another thought crossing my mind:
- Do I completely remove this potential vac leak ridden manifold and swap it for a custom one to future proof it in terms of reliability and future plans
Or
- Simply get busy making good of what I have. It wont be pretty, it'll be blocked off this n that and still potential for vac leaks

Regardless I'm stuck with the standard manifold for now anyway so I'll start to make good what I have. If I choose a different inlet in the meantime so be it


Next part isnt for the easily offended in the car world. Its for those with a level head and open mind of understanding
I notice that folk dont like to see a BMW talked down about, whilst I understand why nobody like to see a car they're enthusiastic about talked down, it does make me wonder why people defend BMW on the build quality of the E46? Especially the early ones like mine. Especially given the common sense that was lacked during it production. BUNA Rubber in an engine was always going to be a bad and almost like it was designed to fail. I'd assume in a bid to make more money, just a shame that making more money trumps making a quality lasting car
The way I've worded it is, BMW designed a brilliant car and the research and planning must have cost of alot of money to get to where they did, its just a shame that what was left of the budget was used for materials, ultimately letting it down.
Before anyone throws the mileage/age question at me like the facebook lot did.. I have another Nissan Micra 1.4 (CGA3) from the same year as this BMW (2000). Other than general wear you'd expect to have to change. All its needed is a MAF sensor. These weren't any car companies Quality years, that disappeared not longer after the 80s. Nissan can make a car a 3rd of the price of the BMW why does it last 3 times longer before any issues (CG engines are good 250,000 before issue assuming well serviced)
Here's my point if you're looking for one and one to bare in mind reading the above. I'm not here to hate on the cars (look at the money I'm planning on putting into said BMW). I'm simply peeved at BMW for letting themselves down and in the end us as owners.
 
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h701micra
So I replaced the Vanos seals today. Waste of time n effort that was. It's still as terrible as before. So at least I know I haven't broken anything

Here's what the car actually does. Temperature doesn't matter it does it anyway

It idles... somehow. Considering the amount of position sensors it still manages to misfire.
Tiuch the throttle lightly and I mean rest your shoes on it. It jumps to 1200rpm. Sits happy and sounds lovely

Press that pedal to 1/3 - 1/2 it'll rev to 2800 and no more that's your lot
Press harder it bogs down hard and drops to 600rpm and something plastic-y starts popping in the engine bay

It's very throttle position dependant on its cocking about

But there's no way to check nor test any form of TPS. There's just a big black box on the side with enough electronics inside to give Bill Gates a hard on but not very helpful for me

Plugged the maf back in. It nearly died on its ass and ran no better. However if you're gentle with the rpm it will rev to the red line... but if you push hard/quick on the throttle it will bog down as before

Ask the BMW lot.. They say one of two things.
Play angry parts with it. It's like angry birds but instead of birds its parts and instead if pigs it's the car
Or
Reflash the DME

Which isn't helpful as it's just guesses


So I'm pretty clueless where to go next. Well I'm not but I feel it

Check fuel pressure
Check fuel pump
Check fuel tank
Check crank position sensor
Check cam position sensor
Change throttle body
After that I'll give up
 
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Sorry to hear of all the issues you've been having - either you're really unlucky or I'm really lucky. I bought a 2001 E46 330ci sport for my gf back in January and we've not had a single issue since...

Seems like a really well built car, not a spot of rust, engine runs perfectly even though it's got 110k on the clock and all the electrics work as they should (including the hydraulic hood).

All I've done so far was change the oil (as I don't believe in BMWs 15k service intervals), all filters and plugs. I also refurbed the MV1 alloys (if you are ever thinking of attempting it - don't, it was one of the most time consuming and tedious things I have ever done).

Only thing that seems to have failed was that the exhaust valve in the tailpipe had seized shut (nothing a hammer and chisel couldn't fix).

Only things I've got down to sort out in the near future are new belts, water pump and thermostat. These look relatively simple to do and shouldn't cost too much either.

Hope you get yours sorted. They're brilliant cars, although it feels a bit heavy round bends to me (probably because it's the vert model and I'm used to driving an RX8!)

Will be keeping an eye on this to see how you get on :)
 
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h701micra
You'll have the M54 engine in a 330. Unfortunately I have the problematic M52TU which is unfortunately plagued. 99-2000 were the worst years. Thereafter they're said to be better, which from your review seems to be the case.
However! I may be on the right track now. More to come later on pending what I find
 
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h701micra
What's changed? Well not much car wise, but understanding wise a fair bit

I cleaned the maf again for good measure. No change

I then did a throttle calibration test
Ign on, don't start engine with throttle down 100% for 10 seconds.
Release throttle for 10 seconds
Start engine

I did an adaptation value reset
Ign on, don't start, for 10 seconds
Off for 10 seconds
Start engine

Hmm idles much smoother compared to before, but still the same issue. And still shakes the car

Then I went back to an old original thought, what about an exhaust blockage, stick hand on exhaust cats.. one below luke warm... one red hot.. so somethings definitely blocked so I shook and hit the hot cat. I garnered a couple of external opinions and there seemed to be an agreement

Whilst testing that, laid on my back touching up its cat converters it decided to quickly rev up to 2000rpm back down and settle to idle... the car then seemed fine.. it revved at any throttle press. Hard or slow. It still stumbled but rather than due it went.. I didn't get my hopes up still

I left it be for some time
Checked all 6 plugs when it was cold.. black... considering its done 0.6 miles since I serviced it... that's pretty obvious somethings amiss..

Cleaned plugs, did all calibration resets again. Started again with its stumbly self, but once cold start enrichment sodded off.. it perked up. It finally wanted to move
So for the second time ever.. it left the driveway. It went up the road just fine, having the blocked cat in mind I expected poor performance as such and that showed, but keep the throttle below half and it was happy

Finally I have a car that does what its designed to do.. drive.
I can go faster than 10 mph.. I managed 60mph without much effort considering.

So im pretty chuffed... it was a day away from being broken for spares too.. so now I'm going to concrete my theory on blocked exhaust, I'm fairly convinced by this point already. Undo exhaust, should be happy from start up (not expecting it to be I suspect extra gremlins here) but once warm I've no doubt

I'll cut the cats out temporarily, if confirmed, to have it at least usable. If it proves worthy of keeping. I'll start looking into a full system and work on it performance wise from there.

I'm not out the woods yet, but I think we're making good progress
 

pollyp

Club Member
What's changed? Well not much car wise, but understanding wise a fair bit

I cleaned the maf again for good measure. No change

I then did a throttle calibration test
Ign on, don't start engine with throttle down 100% for 10 seconds.
Release throttle for 10 seconds
Start engine

I did an adaptation value reset
Ign on, don't start, for 10 seconds
Off for 10 seconds
Start engine

Hmm idles much smoother compared to before, but still the same issue. And still shakes the car

Then I went back to an old original thought, what about an exhaust blockage, stick hand on exhaust cats.. one below luke warm... one red hot.. so somethings definitely blocked so I shook and hit the hot cat. I garnered a couple of external opinions and there seemed to be an agreement

Whilst testing that, laid on my back touching up its cat converters it decided to quickly rev up to 2000rpm back down and settle to idle... the car then seemed fine.. it revved at any throttle press. Hard or slow. It still stumbled but rather than due it went.. I didn't get my hopes up still

I left it be for some time
Checked all 6 plugs when it was cold.. black... considering its done 0.6 miles since I serviced it... that's pretty obvious somethings amiss..

Cleaned plugs, did all calibration resets again. Started again with its stumbly self, but once cold start enrichment sodded off.. it perked up. It finally wanted to move
So for the second time ever.. it left the driveway. It went up the road just fine, having the blocked cat in mind I expected poor performance as such and that showed, but keep the throttle below half and it was happy

Finally I have a car that does what its designed to do.. drive.
I can go faster than 10 mph.. I managed 60mph without much effort considering.

So im pretty chuffed... it was a day away from being broken for spares too.. so now I'm going to concrete my theory on blocked exhaust, I'm fairly convinced by this point already. Undo exhaust, should be happy from start up (not expecting it to be I suspect extra gremlins here) but once warm I've no doubt

I'll cut the cats out temporarily, if confirmed, to have it at least usable. If it proves worthy of keeping. I'll start looking into a full system and work on it performance wise from there.

I'm not out the woods yet, but I think we're making good progress
that's gr8 news. tempted to decat? :p
 
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h701micra
From the manifold back these exhausts are 1 piece.... 1..
The first section looks to 54mm wide... odd size
Got myself prepared with a few pieces of mandrel bent 2" tubing

Cut off the cat and it's a little odd inside
It's 38mm tubing with 2 lines of copper strand either side finished in a 54mm tube... why on earth? I assume for insulation to warm up the cat converters
But how restrictive must that be. That's micra sized exhaust on an engine twice the size. Although they're only responsible for 3 cylinder 1.25l. I guess it's not mega bad but even for BMW that's small.

It goes to 2.5" inch after there the 2 cats and a funky shaped y-pipe which goes square as it forms into 1

So for now I'm as far as cutting the cats out
In the not too distant future I may redo the front pipes and get rid of that twin pipe fiddle further up
 

MaxK11C

#Mallards
Moderator
Social Brand Manager
Great to hear you're making progress! You'll be doing skidz in no time ;)
 
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h701micra
So its been a short while
Near as dam it a month

So what's changed?
It went for its MOT eventually
It struggles like all hell to move when it's cold. Leave it warm up it does hesitate a little but it's much happier

However, take it to 6000rpm it'll make a weird pop and will not rev over 2500rpm.. I only wanted to clear it out. I was being followed so I could drop it off and get home and apparently it stunk sickeningly of fuel... hmm not good

Anyway. Pull over, unplug maf, data reset, start up. Nothing wrong. Stay away from 6k and it drove ok. Once it got really warm its like something clicked in its head and it bloody flew all of a sudden. 70% of the journey I'm pulling more throttle than necessary to move the same throttle saw me in the typical BMW 2 foot from your bumper position. Awesome fun. Sounds bloody epic

MOT. Pair of rear springs later it passed
Advisories were:
Low front pads
ARB drop link
Brake line corroded
Something about my oddly worn front tyre. Both fronts are odd and one more tread thsn the other.. This has been run on a very limited budget

Well, well, well now I was seriously surprised. That's all? Really? Had a good look under the car with the tester. It's not bad at all

Did spot where that gearbox oil leak was coming from. God bless ramps
Also found my knocking noise, prop donut anti vibration shock damping thing was torn. New one required

Sounds like a fantastic car.. then I remembered I had to drive back yet. Reminds me it's not so great
Little to no faith in the engine. But every faith in the brakes they're good
 
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h701micra
Plan of attack over the coming weeks

Check again for vacuum leaks as it feels like it's still got one somehow
Change both coolant temperature sensors
Replace thermostat in doing so I may have to replace the plastic housing as they're prone to crack, no surprise there then

One of my pre-cat O2 sensors isn't getting a signal so as a temporary measure I'll swap the front to back as they've had an easy life
MAF is way out of spec so that needs to be replaced at some point. For now it'll stay unplugged

If there's still issues I'll have a new inlet manifold made that doesn't have so many vacuum take-offs so it can't possibly leak

If all the above doesn't solve its problem
I'll he ditching the BMW management system. Putting in my standalone unit and just turbo the flipping thing
 
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h701micra
I've had another go at cracking this BMWs poor running whilst taking a considerable amount of time doing it.. what used to take 2 hours took me 4 days I'll take it as a sign I'm getting better; this time last week I couldn't stand, so I'll take a positive


Anyway... no more vacuum leaks for sure, I've plugged n sealed every orifice in the inlet manifold.
Meaning this lean condition can't be due to excess air, rather lack of fuel

Which is odd, because the car smells super rich for the first minute or so of running.

Ive also had codes for misfire on all cylinders bar cylinder 1 which I suspect is linked.

Next step is to test fuel pressure, not sure when I'll do it, but its on the list.
I haven't driven it since discovering it was lean, rather not risk it
 
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h701micra
Well the running issue is fixed-ish its now at 95% health

It was a combination of weak/poor connection from the plugs for the majority of electronics. A pick and some man handling later it showed minor improvement.
Acquired myself a known working O2 sensor and changed the one that was functioning but giving the wrong signal. Codes suggested the O2 sensor was telling the ECU that bank 2 was running severely rich, when of course it wasn't hence it leaning out.
Only code thrown was the maf sensor having no signal, being as I'd unplugged it I wasn't worried and hasn't thrown a single code since

Other than a slight hesitation from a quick WOT burst after changing gear the engine runs just fine now.
As the hesitation is speed of throttle related that points me to my DISA unit
Which is said all over , including bmw themselves, to activate at 4000rpm to alter the torque curve by lengthening air flow when in fact when tested it responds to quick/large throttle position changes at any rpm
Being as the car otherwise runs fine, I suspect this "gadget" is the cause
 
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