M5 Guru (>2000 posts)
Join Date: Nov 2008
Location: New England
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Put fresh fuel in and drive it? What needs troubleshooting? You didn't mention how many miles/km are on it or if it runs and starts with a new, fully charged battery. What kind of climate was it stored in?
I'd be prepared to replace the fuel filter after a tank full is run through. Was it stored with a full tank of fuel? Might be considering a fuel pump if not.
If you're asking what I'd like to do, well, that's a lot of work that's probably not really required so I'd recommend driving it and wait for stuff to not work and then troubleshoot. I wouldn't take it on a road trip or to the track. Easy weekend drives of increasing radii until there's a few hundred miles racked up should let you know what's going to require attention.
On the other hand, it might not even turn over and will require starter replacement or overhaul. Then, it might turn over but not run because of rodent or moisture damage or a multitude of sensors not functioning correctly. If it turns over and runs, it may not run correctly due to rodent or moisture damage, a failed or failing sensor, bad fuel, a failed or failing fuel pump, failed or failing ignition coils or fouled spark plug or plugs. If it starts and runs and idles correctly, it might not operate under load because all of the above and more but it might not stop because the long storage period has corroded caliper pistons, slide pins and ruined bores and who knows what condition the brake fluid and pads are in. The tires are most certainly finished and the camshaft position sensors (CPS) are surely the obsoleted versions.
Okay, so what would I do? I'm assuming I don't know the immediate history of the vehicle and this is a fun car and not a primary.
- Purchase and become proficient with a proper BMW diagnostic scanner.
- Top up all fluids then get it to turn over.
- Replace the fuel and fuel filter and have a fuel pump on hand. Purchase new MAFS and CPSs.
- Start it, just get it idling and the engine up to temperature first. Monitor for leaks. Purchase new brake rotors, calipers, pads, lines and brake fluid.
- Replace the spark plugs, engine air intake and cabin filters. Get an oil sample analysis kit from Blackstone Laboratories. Purchase oil separators and associated hoses/grommets amd valve cover gaskets.
- Check all fluid levels again and top off as necessary. Purchase new engine coolant thermostat, water pump, expansion tank, hoses, radiator and coolant/antifreeze.
- Drive around slowly and make sure it rides and stops with no issue. Purchase and install new tires.
- Check all fluid levels and top off. Purchase engine oil and filter, transmission and differential fluid.
Prepare to change engine oil and filter, transmission and differential fluids and engine coolant, water pump and thermostat, brake pads/rotors, etc. You may prepare for engine coolant radiator and expansion tank if you like at this time.
Drive it not around other cars or people. Listen for noises, monitor brake performance, check for leaks. Light at-speed operation is desired because you want to get the entire drivetrain to operating temperature.
- Get back home and replace the engine oil and filter while obtaining a sample for analysis. Drain and refill the transmission and differential. Replace the engine coolant system (radiator and expansion tank optional) and oil separators. Replace the CPSs which you might find easier with the valve covers off. Replace the brake parts at each wheel, bleed the brake fluid and replace it. Replace the MAFS. Purchase new O2 sensors.
- Drive it. Increase the distances slowly and suss out other problems. Expect it to not run super smooth at first as the car gets used to running again and the DME adapts to the new operating conditions. Pay attention.
2/2001 M5, Jet Black, Exclusive Complete Black Walk Nappa Point Heritage Leather, Black Cubic Trim
8/2011 X5 xDrive35d Sport, Black Sapphire Metallic, Black Nevada Leather, Fine Burr Walnut Trim