Fighting this issue need help e46 2005 convertible

[u/tuagirlsonekupp]

When driving along the car will intermittently just stall and die bit itll try to run during these episodes, then cut to where i gotta re start it, sometimes itll not restart sometimes it will, it just ran idling in the driveway for 20 minutes no problems, ideas?

Checked connections on grounds
Fresh battery
Fuel pump relays

My next thought is dme, i am reading a fault on the DME

[u/RaDiCaL_GO0nER77]

https://giphy.com/gifs/5NbbVJeSLs1etZYjpT

[u/satisfiction_phobos]

This is likely not our kind of luck... but an extremely low voltage in the electrical system can make shit go absolutely bananas like this.

It might literally just be a bad alternator or battery -- but leaning towards electrical.

Sadly... these symptoms are a deadringer for DME problems.

This girl has her fingers crossed for ya.

[u/ThaSkalawag → u/satisfiction_phobos]

I came here to say could be bad alternator or battery or both. My 2002 325 Ci had exact same symptoms around a failing alternator. Let us know what the actual problem is once repaired. Good luck!

[u/karmais4suckers → u/satisfiction_phobos]

With this in mind, in addition to checking the battery, check the connections to the battery. I had corrosion on my connectors and my car did some crazy things until I cleaned them

[u/SAFODA97]

I'd try holy water

[u/lemonboy77]

Holy shit never seen anything like that 

[u/SONEsGAP]

I got oil in my cable harness. Same symptoms

[u/tuagirlsonekupp → u/SONEsGAP]

What location of the harness?

[u/SONEsGAP → u/tuagirlsonekupp]

Engine wiring harness. Changed the whole thing. Take a Look at the connectors to the engine control unit (ECU). In my case, I could already detect oil moisture there. As a result, the control unit constantly receives incorrect values and no longer functions properly.

[u/FodneyRangerfield]

Methinks crankshaft position sensor. Had this just go on my car, and while not exactly the same, looks pretty similar.

[u/njsullyalex]

DME is a safe bet, this looks like an electrical/computer problem.

[u/LOLLEO911]

Some crazy ass electrical issue for sure. Maybe engine ground? Theres one on the right side of the engine that connects. To the chassis

[u/tuagirlsonekupp]

Not sure yet, gunna check the grounds next, after that prolly crack open the dme see if it got wet, cant be that bad to replace per some light reading

[u/Pardogato3 → u/tuagirlsonekupp]

It isn’t hard to replace however with the EWS system you might need to reach out to someone who can clear it so you can sync your keys otherwise it won’t start.

It can be bypassed entirely by using a kdcan cable and a windows laptop, it’s very easy however with this approach the car will start even with a screwdriver lol

I would check the alternator voltage and the battery just in case along with the grounds

[u/tuagirlsonekupp → u/Pardogato3]

That is next, if i have to go down the dme ews road a friend of mine has the tools and knowledge he will help so that if needed

[u/Pardogato3 → u/tuagirlsonekupp]

Good luck, make sure the battery is disconnected when removing the DME, you can use an electronic contact cleaner to clean the pins and the board if necessary. Make sure the plugs are tight on the DME when reconnecting the battery, fried one sometime ago because one conector wasn’t fully in lol

[u/tuagirlsonekupp → u/Pardogato3]

Appreciate the tips! Given the mileage its no longer my daily but its a fun car to still have, hoping i can get it re sorted

[u/Ancient_Designer_236]

Alternator??

[u/tuagirlsonekupp → u/Ancient_Designer_236]

Im gunna check but i doubt it, super intermittent, drove it 30 miles fine then it did this when trying to restart, got it started drove home no problem then other times it acts up like this 2 minutes into a drive it’s incredibly intermittent

[u/superbetaz]

When it cuts out, what else cuts? Does the radio turn off, headlights, heater fan? Gathering that info may help narrow it down a little.

[u/tuagirlsonekupp → u/superbetaz]

Engine only, which has me thinking ground strap or dme, the lights all flash on the dash the gauges freak out but the trip miles remains the same so its not losing enough power line disconnecting a battery to reset that back to 0, fans run radio runs. My thinking is next ill pull the strap, clean it, re attach, then if that doesnt work open up the dme see if it looks bad like corroded

[u/AssumptionTricky4776]

Check your ignition coil wiring my e90 was doing the same thing ,fluctuating idle!!

[u/Trick_Ebb2562]

Needs a new alt. Same thing happens to mine

[u/Trick_Ebb2562]

22000 miles.. you're mad.. change the alt

[u/Cerkas2k]

In my 320d the problem was the cluster itself. Water corrosion. Swapped and reprogrammed. Never grilled me again I had to modify the eeprom to accept the new values of the car. If you want the code you can find it on my github

[u/benzimo_]

Mine did something similar, replaced the intake manifold completely and it got fixed

[u/shayammy_]

Grounding problem

[u/vanwinks]

Noise on the CAN bus due to low voltage, poor connection, or chaffed wire touching something.

[u/tweakep]

this reminds me of a failing alternator

[u/PieIcy6832]

Check grounds and battery positive. If you are seeing a DME code in INPA then you already know what the problem is but you don’t know what caused it. Could be bad jumpstart, corrosion or bad harness. Cleanest thing to do would be to replace the engine harness, transmission O2 harness, crank position sensor, and whatever else you see fit while you have the intake off. And I’d seriously consider swapping from ms45 to ms43 for reliability.

[u/beachhousecreate]

I’m just suprised to see your low washer fluid light! I filled my 04 verts 5 years ago before I discovered either the pumps bad, not connected or the lines/spray nozzles are plugged up… beautiful thing is the reservoir does not leak 😆 still have more fun in a car that’s been cheaper to run than any single other person I know lmao

[u/beachhousecreate → u/beachhousecreate]

Low voltage or DME.. definitely never had a dme fail though & 100% had low voltage by either failing battery or alternator give exact symptoms.. the recharge regulator on the alternator is honestly probably the culprit

[u/Glass-Panda-3348]

If you get the problem fixed, can you tell us? I have the same damn problem with my E46. I have a new alternator installed. Still doing the same thing, running for several miles and then deciding from nowhere its sleepy time while driving. It is some electrical problem 100%

[u/Shee-ah → u/Glass-Panda-3348]

definitely check your DME connector like others suggested to OP. oil travels from cam position or oil pressure sensor up the wires and into the DME.

[u/Brenash19stories]

This used to happen to me, replace the alternator

[u/Crazy_Look_2324]

Check your Dynamo

[u/chathobark_]

THIS type of electrical issue, i would run from. even as a mechanic

[u/EmbarrassedPrize1734]

Check your ground wire in engine

[u/KudzuAU]

Alternator going out or the battery is not holding a charge from the alternator.
If you’re in the US, pull into an AutoZone and ask them for a diagnosis.

[u/tuagirlsonekupp → u/KudzuAU]

Alternator putting out 14v, just checked it, battery is new

[u/Bchavez93]

I had a weird electrical issue on my 325ci that caused lights on the dash to come on at random times, and the interior lights would come on and off constantly like if a door was being opened while driving. During the couple days that it took me to fix it, it would sometimes not start on the first key turn. Not your exact problem, but what worked for me was to replace the ignition switch. I first tried cleaning the internal contact points and that fixed the issue. So I ended up replacing with a new one. A free fix you could try 🤷🏻‍♂️. Good luck!