What did you mess up, by working on your own car?

[melanthius]

Installing BBK on my old 350Z. Didn't know I might need wheel spacers to clear calipers, no one had this BBK combo with my wheels so I wasn't sure. The wheels generally had good clearance by the looks of them, so basically I was clueless.

Installed everything, wheels fit, I wasn't even looking at the clearance at that point.

Front wheels literally had -0.01mm clearance to calipers, they fit perfectly but were seized and couldn't turn.

Ended up chipping the paint badly on beautiful calipers and couldn't drive for a couple days while waiting for spacer to come in. By the way I was occupying a lift at my workplace while this was happening.

[ICantDrive4Sht]

Broke one of the bolts that holds the carbon structure in place on top of the engine.
It's still in place so guess that bolt wasn't needed anyway.

[Hotflare]

Buddy and I swapped my entire interior from black to S.O. ... but before i went to unplug the battery, he unplugged the driver airbag... so now i have the damn warning light

[damageprone]

https://f80.bimmerpost.com/forums/sh....php?t=1537829

This thread is a classic. Although it wasn't my mistake, I did learn from it and had a clean install.

[M4theWIN1]

While changing the mirror caps from standard over to carbon, somehow the cap slipped from my grasp during install. Caught it on the fly down before it hit the pavement. Problem was I caught it against the car with the tabs facing the paint. Just awesome. Had a nice 3-4" long scratch in the paint. Talk about making one feel instantly sick. Took about two hours to work the panel with a polisher. Thank god it came out. Lesson learned - let that cap hit the pavement!

[dezzracer]

Thought I had found a hot wire to power my radar detector in my 04 Mustang Cobra. Clamped a wire tap to it. No power. Turned out it was the pressure line to my boost gauge. Errrrrr….

[RoundelM3]

Nothing, actually - but I've got a good bit of mechanical/electrical background. For those that don't, there is this quote from Inspector Harry Callahan:

"A man's got to know his limitations!"

[Adcampo]

Nothing on my M car, but a few years ago, I installed an OEM sport exhaust on my 991. It was a fun DIY until I got a bunch of vacuum lines all mixed up. After a couple of days of frustration, I took it to the dealer. That DIY project cost me $500 in labor.

I also changed the serpentine belt. Part of the process is removing a long carriage bolt. When in went to reinstall it it wouldn't line up. I was freaking out. A quick rennlist post and learned I had to jack the engine up a few millimeters.Lessons learned trying to renew my man card.

[MetzgerMeister]

Oh I've had a few.

On my RX8 I did a DIY engine clean using water, WD40 and a plastic bottle with a tube connected to the port nipple. Did the job well but in the process it blew a very expensive O2 sensor.

My first time replacing the spark plugs on the RX8 I completely mixed up the ignition wires. It didn't cause any problems but it could have. Only had a short drive before I fitted a different set of plugs to see if there was a difference.

On my Mazdaspeed6 (Mazda 6 MPS here in Ireland) I removed the EGR to clean it out as I had an error on my dash. Everything put back together and went for a test drive to find no boost pressure at all. Went through the engine bay ensuring everything was tightened and found that the charge pipe was loose. Again down to my impatience to get the job done on a wet, cold Irish day.

On my F30 I was chasing a rattle/buzzing noise coming through the air vents. Did loads of cleaning etc (to remove supposed leaves) which required removal of the blower unit. Low and behold 2 of the hanger type things where the screws go cracked off. I ordered a second hand one from ebay only to open it up and find the other screw hanger broken off in the box.

Eventually I ordered a brand new blower unit only to find that it wasn't the cause of the issue but vibration from the engine caused the lower A/C pipe to vibrate and this noise is what was coming through the vents. I got the weight from BMW but sold the car before I got a chance to fit it. Lots of time and money wasted on shipping back and forth. Thankfully I got full refunds for the units each time.

My most recent mess up was a week ago when I tried replacing the M badges on my seats. I had the new black ones and couldn't wait to replace them. I pulled out the old ones only to find that this job had been done before which left very little cabling to work with. I gave it a go anyway and ended up messing it up and having to snip the cable and try again further down until it got to a point where I ddin't have enough cable to work with.

Next step is to slip off the leather and remove the cable altogether so I can do the job on a bench properly with solder and extend the cables if needs be. Kies Motorsports made it look so damn easy!

[Silverlining_m2]

Originally Posted by RoundelM3

Nothing, actually - but I've got a good bit of mechanical/electrical background. For those that don't, there is this quote from Inspector Harry Callahan:

"A man's got to know his limitations!"

Lol well look at you fancy Sir! We're learning too.

I'd say that quote is foolish, as a man who wants to learn, and takes the effort, only has the limitations he places on himself.

Similarly, I disagree with the quote "the definition of insanity is repeating the same action and expecting a different result"...
Because if that's the case, then what is "practice"?

[SMB F83]

I went through a phase where I had miatas. I'd done enough timing belts on them I got complacent and just did them without checking reference materials.

If you've ever done cam belt work on a miata, you've probably seen that both sprockets have E and I markings on them, and oddly enough when you're timing then, the intake cam uses the E marking, and the exhaust the I.

Of course this time I put them on reversed and timed the belt to E on Exhaust and I and intake (logical, right?)

After god knows how long wondering why it wouldn't fire after it was all buttoned back up, I finally pulled out my phone to check the markings, realized what I'd done, and spent another 2 hours re-doing the cam belt job to swap the sprockets.

Didn't mess anything up, but still one of those smack your head moments.

[jmg]

Dropped the brake fluid reservoir cap into a narrow bottomless pit in the engine bay while taking the car off the jacks. I spent the next 20 minutes Macguyering a hanger and duct tape and fishing it out. If fell back into the pit more times than I can count and I never said anymore curse words in such a short amount of time before in my life.

[jmg]

Originally Posted by dezzracer

Thought I had found a hot wire to power my radar detector in my 04 Mustang Cobra. Clamped a wire tap to it. No power. Turned out it was the pressure line to my boost gauge. Errrrrr….

Sorry but my wife is now wondering why I'm laughing while taking a shit.

[HarryTee]

Originally Posted by jmg

Dropped the brake fluid reservoir cap into a narrow bottomless pit in the engine bay while taking the car off the jacks. I spent the next 20 minutes Macguyering a hanger and duct tape and fishing it out. If fell back into the pit more times than I can count and I never said anymore curse words in such a short amount of time before in my life.

When I buy a car, I always take the A-pillar trim off to hide in the pillar the wire from a webcam I'm installing. In my first BMW that I installed the webcam, the plastic clips that held the trim to the A-pillar kept falling off into the dark hole at the bottom of the A-pillar. I kept replacing them with new ones and the all fell down the hole. I honestly don't know where the hole leads to. Hopefully to outside of the car when the clips reach the bottom

[AdnanH35]

Decided to change the rear brakes on my 2016 x3 and accidentally tore the piston rubber seal when retracting the piston. Brake fluid went everywhere. Looked for a caliper rebuild kit and couldn't find one. Eventually had to buy a whole new caliper for $300 :/

[AlterZgo]

Originally Posted by F82spaceship

Lol well look at you fancy Sir! We're learning too.

I'd say that quote is foolish, as a man who wants to learn, and takes the effort, only has the limitations he places on himself.

Similarly, I disagree with the quote "the definition of insanity is repeating the same action and expecting a different result"...
Because if that's the case, then what is "practice"?

I agree with your first point but disagree with the 2nd. Practicing the wrong thing is often the worst thing one can do to improve. If Ben Simmons is shooting free throws with the wrong form he needs to stop practicing his broke ass form and actually change his shot first before practicing shooting more free throws. So in his case, yes, continuing to practice his shitty form IS insanity.

[Silverlining_m2]

Originally Posted by AlterZgo

I agree with your first point but disagree with the 2nd. Practicing the wrong thing is often the worst thing one can do to improve. If Ben Simmons is shooting free throws with the wrong form he needs to stop practicing his broke ass form and actually change his shot first before practicing shooting more free throws. So in his case, yes, continuing to practice his shitty form IS insanity.

Touché!

I guess I make a point of practicing the right things and have never considered that one might not

[ntg44]

My most expensive mistake was on my 09 WRX. Was DIYing the "plug and play" SPT boost gauge. Snapped the bolt right off the turbo when taking off the intercooler to reach the firewall grommet, so had to drill it out. I thought the worst was over.

I was struggling to get the vacuum line through the firewall so I decided to guide it with a flat head. Well I got it through eventually. Things are looking up.

As I'm working my way around the footwell to fish the lines up to the dash, I see smoke. The car hasn't been running for hours, so something didn't seem right.

Well, turns out when I got the vacuum line through the firewall, I jammed it right through the AC condenser, causing a leak

I threw in the towel and took it to my mechanic. $1000 repair bill in parts and labor, all to save $200 on a boost gauge install.

Now I stick to cosmetics

[JamesGames]

Every time I work on my car I must break some plastic clips. If the car is old then I must break clips / hoses / connections / random brittle plastic. Seems like BMW likes to use biodegradable plastic / rubber... ha

I just removed the PCV hose / valve on my E60 (15 year old car) and the whole damn thing snapped in 2 places. Lack of patience doesn't help, glad I had a spare one ready to go (I predict these things now).

[agentrnge]

Originally Posted by JamesGames

Every time I work on my car I must break some plastic clips. If the car is old then I must break clips / hoses / connections / random brittle plastic. Seems like BMW likes to use biodegradable plastic / rubber... ha

The gods of plastic clips always demand their sacrificial offerings.

[HyeM3]

Somehow a license plate screw got cross threaded into the trunk so I guess my plate will forever live with the car

[hardrock]

As a kid, I had built a lot of small block Chevy engines. I decided to rebuild the engine on my 2004 2002. While doing so, in my driveway, I let a rod cap get away from me. They weren’t marked as to the correct orientation, so I guessed - wrong.
When I put it back together, I lost the rod bearing almost immediately. OUCH!

The dealer is my friend now.