2003 BMW 330i (E46) Project

[intoxicated]

The problem is never going to fix with a fluid change, you have a mechanical failure in that unit. You can refurb it for cheap money as long as its running through all gears - a rebuilt TC is not much dough either.

Ask around for shops that can refresh a 5spd ZF if you supply the unit (meaning you DIY the removal and install)

I usually use Ford Mercon V or Toyota T-IV in old ZF 5 spd boxes. It works pretty decent.

Yeah I was told the same, if there's a TC code, it won't go away unless TC is replaced. I found a bunch of refurbed units on ebay, so TC DIY it is instead of fluid flush, I'll look at replacing the unit.

[intoxicated]

how did you conclude that the clutch is dying? Have you checked its airgap? That can cause a fail to engage situation sometimes - but the compressor is supposed to cycle on and off while working.

Is your system overcharged a bit by any chance? - Is your fan clutch working proper? how about the front fan?

It was most likely overcharged, I did let a lot of the refrigerant out and the cooling seems to be correct but the issue still remains (while driving it cools fine and does work for a few minutes at idle after driving but then clutch stops staying engaged). All relays/fuses are fine - if it was an electrical (relay/fuse) related issue it won't turn on at all. Before letting out some of the refrigerant compressor clutch would engage every 15 seconds and continues going in this loop and after releasing refrigerant it now engages and disengages every 45-60 seconds and stays engaged for 5 seconds and disengages.

I had replaced the clutch fan with an electrical fan (front fan was removed) and the fan comes on as soon as the clutch engages but it disengages in a few seconds with compressor clutch.

[Xulfiqar]

If you find the TC snout scratched up - you need to pull the pump and refurb it, then redo the pressure regulator in the valve body so it doesnt lose lube volume again.

a good transmission shop would know this - cheapo weirdos who only run on replacement transmission as "transmission service" wont.

[Xulfiqar]

do you have anything to see the high side of the system? - did you add any fancy "refrigerant" by accident? - like something called leak stop or chill etc etc.

[intoxicated]

I don't have anything to see the high pressure side at the moment - I did add half a can of the so called leak stop but I was having issues with the system already and release a lot of the refrigerant or I feel the system didn't take much of it anyway.

I'm looking at getting a kit with vacuum pump, do pull a vacuum on the system and refill correctly.

[Xulfiqar]

I did add half a can of the so called leak stop but I was having issues with the system already

fateha on your ac, the leakstop plugs up the expansion valve and will destroy the valve plates in the compressor too.

you know how to repair and flush a car A/C?

[intoxicated]

I did add half a can of the so called leak stop but I was having issues with the system already

you know how to repair and flush a car A/C?

Lol I don't but I'll figure it out - any tips/suggestions?

[Xulfiqar]

you need to buy an air compressor, a flush gun, flushing solvent, a new TXV, a new drier and all new O rings - then dismantle the entire AC system piece by piece - and use hoses to clear out the system of old old and solvent.

Then start assembling from scratch.

tip: - use corktape to seal up pipes that can sweat inside the cabin or in false firewall and also use it to insulate expansion valve.

[intoxicated]

Quick update:

Even after replacing the radiator the overheating saga continues. Two incidents that really made me reconsider keeping the car - so this is up for sale because I have my hands full with the X5 and needed one car to be fully functional and issues with the E46 were becoming a headache.

1. I was traveling and parked the car at the airport for a week and on my return the darn bleeder screw leaked and I had a quite an adventurous ride back home - bought the replacement on my way back but the bleeder screw top broke and I didn't have tools to pull out the rest, so had to stop several times to make it back home.
2. It overheated in moderate traffic and had to be towed home.

Diagnoses: turns out the temperature sensor may not be functioning right - radiator fan does not kick on with the temperature (it does turn on with A/C though) - so I'm hoping all my A/C related, transmission and heating issues may just be related to the temperature sensor - and now that I think back, I've had these symptoms for a while because I've mostly traveled on highways so did not need the fan very much anyway and whenever I was in traffic of stopped at a night, coolant temperature would get as high as 235 F.

So I'll replace the sensor today and report back on where things are.

[intoxicated]

I replaced the coolant temperature sensor but it didn't resolve the radiator fan issue - after further diagnoses, turns out it's the "final output stage" sensor that's not functioning right and it comes with the fan as one assembly (it was a junkyard fan that served me well for 4 years) - replacement fan is on the way.

Will see how it goes.

Old vs new coolant temp sensor

Quick clean up this morning

Washed this too

[intoxicated]

Finally the overheating issue has been resolved, turns out the fan assembly was on its last leg and wouldn't kick on at the right temperature.

Old vs new fan

Also took the opportunity to clean up the interior of the car.

[intoxicated]

So this DIY comes to an end. E46 has been sold - this thing served me well for over 4 years.

[Xulfiqar]

Why did you sell it after fixing it up?

Btw

I usually do a complete cooling system overhaul on these old bmws at the 12 year mark. No need to nickle n dime it.

[intoxicated]

I never had the time to fix it, so sold it as is - sold it for more than what I paid 4 years ago

I agree - I had done all hoses to stay within budget at the time.

[VCheng]

Ah, the joys of owning a German car out of warranty.

[Xulfiqar]

Yep

Theyre awesome, you can get em for low money and are a reward own (if you like tinkering like myself)

[VCheng]

If one provides the labor for free, they can be good bargains for those that enjoy that kind of thing. After all, there is a reason for their fierce depreciation.

[Xulfiqar]

You bet

The rest should drive cheapo cars and leave these to crazies like us.

[intoxicated]

You bet

The rest should drive cheapo cars and leave these to crazies like us.

Haha they certainly are a treat to drive.

[VCheng]

It overheated in moderate traffic and had to be towed home.

Is the treat in how they overheat, or is it while they are being towed home?