what do i have?

im a first time bmw owner and wondering what i got myself into this time. i have been doing some research and getting conflicting information. maybe you guys can help.

i bought a 1986 bmw 535i on wiki it says my car has a 3.4 engine in it. however when i run my vin number it says i have a 3.5. can someone tell me what i really have?

also the car needs a little work. interior and exterior are in good shape. but previous owner said the air intake tube had a hole in it so he rigged up a rubber hose and some silicone to get it to run. it has a very bad exhaust leak and i notice the o2 sensor under the car is unplugged. the car will start and idle very low. spits and sputters, oil light comes on and after a few minutes it will die if you dont give it gas. taking off from a stop sign it wants to cut out and sputter unless you give it full throttle and even then it seems very under powered.

also, in the world of bmw where does my car fit in? i paid 2000 for it as it sits. hoping it will be worth the investment once i get the problems figured out. car has 152k miles on it.

thanks in advance for all your help

Start doing some searching about intake/vacuum leaks. You can also search on www.mye28.com. Get yourself a Bentleys manual to help you diagnose and repair your idle and other problems. If you want it to run well, it sounds like you're going to have to do some work to it. You probably need to replace the O2 sensor and maybe even the catalytic converter. The price you paid is Ok if you like it and plan on keeping it, but you will need to spend a few bucks to get it in order. You may want to go to RealOEM.com to look at the available diagrams to figure out what intake and exhaust parts you need to replace. Try to stick with stock, it's all available.

Well this morning I started it, drove three miles spitting and sputtering to the shop, it died as I pulled in. Now it will crank but not start. If I let it sit a few minutes the car will almost fire and the go right back to cranking. I pulled off a fuel line that goes to a fuel filter bolted to intake. Gas does shoot out of the filter during cranking

I did notice charred wires and corroded tubing coming from the top of the engine where the two large radiator hoses go. But looks like its been that way a while

Originally Posted by cmartin7x

Well this morning I started it, drove three miles spitting and sputtering to the shop, it died as I pulled in. Now it will crank but not start. If I let it sit a few minutes the car will almost fire and the go right back to cranking. I pulled off a fuel line that goes to a fuel filter bolted to intake. Gas does shoot out of the filter during cranking

I'd replace the plugs and take a good look at the wires, distributor cap and rotor, clean out the IAC valve, clean the throttle body, clean the Air Flow Sensor, check ALL the hoses and boots for vacuum leaks, check the condition of the air filter, pour a can or two of fuel injector cleaner into the gas tank just to get started. Your car has two fuel pumps; one in the tank, one under the car. The fuel may seem under pressure, but if one pump goes out, it is usually inadequate. You may want to check the pressure. When you change the plugs you may want to take a compression test. A valve adjustment at this time is also probably neccessary.

could someone tell me firing order and labeling for cap and cylinders. for some reason i took the air filter off and it seems to be running a little better. very rough idle. it idles at 500 rpm. once i get it up to 1500 or so it smooths out nicely

and....dumb question. what is the thing under the gas peddle that is spring loaded?

Originally Posted by cmartin7x

i bought a 1986 bmw 535i on wiki it says my car has a 3.4 engine in it. however when i run my vin number it says i have a 3.5. can someone tell me what i really have?

Hi

The displacement varies between 3430cc and 3460cc so some ended up being registered as a 3.4L and others 3.5L depending on where in the world they were sold. I'm open to correction on this, but thats my understanding.

Sounds like your air filter is also clogged up and due a replacement, along with the other bits and pieces suggested. Once done and running right again though, you'll have a fine motor and should get plenty of years out of it. The bottom end on these is good for 300k miles and has powered BMWs since the late 60s

Firing order is 1 5 3 6 2 4 - with 1 being closest to the rad and 6 at the bulkhead. link for pic of cap number sequence http://forums.bimmerforums.com/forum...d.php?t=991650

The thing under your gas pedal is to stop you punchin it to the floor I would imagine, either that or its to do with the kick-down for the auto?

problem solved, im so happy. thanks to everyone on here for your help. turns out it was a fuel pump relay gone bad. i checked it5 times and thought it was fine. then i saw i was checking the wrong relay. i was going by the clear plastic cover markings and it was showing that relay closet to bumper outside the box was the fuel pump. but it was actually the second one from the bumper. runs like a champ now

That great news!! Glad you got it sorted. Happy motoring now