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I fixed a parasitic drain on my car in 408 days

davidmuller.github.io

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Re: I fixed a parasitic drain on my car in 408 days

#211

Post by ryandrake »

karolist wrote: post #200
ryandrake wrote: post #188

Earlier quoted context omitted.

Your friend’s fuel issue seems a lot like the intermittent no-start, low fuel pressure issue I have been debugging (3-series) for over a year now. It has defeated three dealerships and two independent mechanics so far, so I’m taking over the diagnosis now. No clue yet but today’s cars have too damn many computers in them.

which engine is that? I had an N54 335 for 5 years too, even E36 era BMWs have vastly superior error logging compared to JDM from that vintage. I hope you find your issue, but if it defeated dealerships it sounds troublesome. Log some live data with INPA if it's an older one, I have no experience with BMWs post EXX series to drop any advice...

Yea, N54. INPA helps confirm things, but just the idea that you have to pour over logs to diagnose a system that should be simple and straightforward... sigh. My last car was from the '80s and you could wrench pretty much anything you needed to without having to negotiate with a dozen computers running the show.

Re: I fixed a parasitic drain on my car in 408 days

#212

Post by linuxftw »

jxramos wrote: post #196
stuff4ben wrote: post #129

Earlier quoted context omitted.

That usually doesn't work anymore as mechanics can tell that you've done that when hooking up the ODBII port.

I recently noted in my OBD2 scanner that some vehicles support the measure of miles since check engine lights were cleared or something to that extent. It made me ponder at some point in the future there is going to be regulation mandating that to pass an emissions test you must pull up to the test station with a minimal threshold mileage on the car to vet no check engine lights have tripped in that interval.

That's already a thing. Many sensors will be in 'learn mode' and you can't pass emissions until they are fully active.

Re: I fixed a parasitic drain on my car in 408 days

#213

Post by karolist »

ryandrake wrote: post #211
karolist wrote: post #200

Earlier quoted context omitted.

which engine is that? I had an N54 335 for 5 years too, even E36 era BMWs have vastly superior error logging compared to JDM from that vintage. I hope you find your issue, but if it defeated dealerships it sounds troublesome. Log some live data with INPA if it's an older one, I have no experience with BMWs post EXX series to drop any advice...

Yea, N54. INPA helps confirm things, but just the idea that you have to pour over logs to diagnose a system that should be simple and straightforward... sigh. My last car was from the '80s and you could wrench pretty much anything you needed to without having to negotiate with a dozen computers running the show.

I loved my N54 dearly, HPFP is a consumable item there though (30-50k miles), I'd change that as a precaution, especially if your car is tuned.

Re: I fixed a parasitic drain on my car in 408 days

#214

Post by Nifty3929 »

jobead wrote: post #201
Nifty3929 wrote: post #193

Earlier quoted context omitted.

What are coded parts? I spent a minute googling and couldn’t come up with anything that seemed right.

I believe this means that the part's computer has the vehicle's VIN loaded into it with a computer that can only be purchased/used by a certified technician. If he was to buy a new part, it would have a blank VIN; and if he pulled one from a junker, it would have that car's VIN. (edit: should also say, I think a VIN mismatch would cause the ECU to refuse to work with that part and shut down)

Well that's dumb. I've never heard of that before. But I guess I shouldn't be surprised. Thanks!

Re: I fixed a parasitic drain on my car in 408 days

#215

Post by gonehome »

lylejantzi3rd wrote: post #28
overthrow wrote: post #3

Well this is timely. I have a parasitic draw on my NC Miata. The first mechanic just replaced the battery. The second told me it's normal for the battery to die if you don't drive it for 3 days (because "cars have computers now"). It seems like mechanics really don't like digging into the electrical part of the car... but these days that encompasses more and more of what can go wrong. Without time to dig into it myse…

> It seems like mechanics really don't like digging into the electrical part of the car... Tell me about it. I'm in a similar boat. My audi a4 has had a parasitic draw for the past 10 years. My mechanic didn't want to take the time to address it because that sort of thing takes a serious amount of time and he's always backed up. I got out my fluke and narrowed the cause to what I believe is the comfort control unit.…

If you’re going to have to deal with it might as well get a tesla which is at least all in on the electronics and the company understands software.

The dealership model has really been awful for legacy manufacturers.

Re: I fixed a parasitic drain on my car in 408 days

#216

Post by johncalvinyoung »

JPws_Prntr_Fngr wrote: post #204
legitster wrote: post #160

Earlier quoted context omitted.

That's fair, but it's funny because that's how I always felt about BMWs. My buddy loves them but I always felt like they were so... sterile. Unless you are at a track or love cutting off people in traffic it feels really hard to have any fun in one.

Sterile compared to what? Is there another manufacturer of acceptably-tuned rear-drive sedan chassis out there at a semi-reasonable price point that I should know about? (I'm talking about pre-2010 BMW here; I would totally agree with most new ones being sterile)

As a current owner of a 90s Jaguar and an 05 Volvo, I've been looking at low-mileage E90 era BMWs for my next daily driver. Not too scared of moderately expensive maintenance, but would like it to be more reliable than the Volvo has been.

Re: I fixed a parasitic drain on my car in 408 days

#217

Post by johncalvinyoung »

EricE wrote: post #127
ghaff wrote: post #46

Earlier quoted context omitted.

I don't have extensive experience with my current car bought last summer but 2 weeks in warmer weather definitely wasn't an issue. I agree colder weather is always a bigger issue and at 1-2 months I'd definitely be thinking of a trickle charger if at all possible. An older car I didn't drive in the winter would definitely end up with a dead battery if I didn't keep it on a charger.

AGM batteries are a lot more durable than regular lead-acid. They can cost a bit more but for me the longer life, more resistances to issues if you do run them all the way down and their sealed, maintenance free nature makes them the first thing I swap out. Optima used to be the only commonly available batteries but Costco, for example, has AGM equivalents for just about every battery out there - you may have to orde…

I must have had a bad run of big H8 AGMs in my Jag and Volvo. I think I've replaced about one a year on average. The Jag is very subject to parasitic drain and sometimes it just didn't come back from running itself out.

Did the Miata not come with a hole in the trunk floor for an exhaust hose for the battery? Both of my cars did...

Re: I fixed a parasitic drain on my car in 408 days

#218

Post by jopsen »

peteradio wrote: post #86
nickff wrote: post #62

Earlier quoted context omitted.

The problem with specializing in these issues is that most customers will be dissatisfied when you charge them thousands of dollars to reset a minor module on their car. How many hours of shop time are you willing to pay for with no guarantee of a solution, and very few (if any) parts replaced?

Dude's been tending his issue for a decade, I bet he'd have at least those like him as a customer. In a metro he might have a pretty lucrative business. On the other hand in the metro there is probably someone who already does this work, but they are very hard to find!

How do potential customers find your specialized shop?

Most people will give up, stop researching and buy a new car when the dealer tells them it can't be fixed.

Re: I fixed a parasitic drain on my car in 408 days

#219

Post by jopsen »

nickff wrote: post #62
lylejantzi3rd wrote: post #28

Earlier quoted context omitted.

> It seems like mechanics really don't like digging into the electrical part of the car... Tell me about it. I'm in a similar boat. My audi a4 has had a parasitic draw for the past 10 years. My mechanic didn't want to take the time to address it because that sort of thing takes a serious amount of time and he's always backed up. I got out my fluke and narrowed the cause to what I believe is the comfort control unit.…

The problem with specializing in these issues is that most customers will be dissatisfied when you charge them thousands of dollars to reset a minor module on their car. How many hours of shop time are you willing to pay for with no guarantee of a solution, and very few (if any) parts replaced?

> How many hours of shop time are you willing to pay for with no guarantee of a solution, and very few (if any) parts replaced?

Imagine opening a computer software support business where you bring in your old proprietary binary programs that you got from who knows where, and the business is to fix bugs you've found.

Maybe some really big enterprises would pay for that sort of thing. But I doubt it would be feasible for consumer stuff.

It would be a crazy/fun kind of business to run. I'm sure it probably exists.

Re: I fixed a parasitic drain on my car in 408 days

#220

Post by wisosim »

sixstringtheory wrote: post #152

Hah. I’ve replaced the battery in our Subaru Outback on average once per year, which is way too high for this environmental minded person. I just went out last night to grab something from the car and it was making a loud electrical whirring noise. I had driven it several hours prior, no idea how long it had been going. I recorded a video and it is clearly audible. I started it and turned it off again, and the noise…

That whirring noise is likely from the EVAP system of your Subaru. See below threads for more info about it. Having to replace your battery once per year is not normal though so there is definitely something else going on.

https://www.clubcrosstrek.com/threads/buzzing-sound-from-pas...

https://www.subaruxvforum.com/threads/whats-that-sound.14672...

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