cars running rough

[318driver]

its a 91 325i cab, and its been sitting for 3 yrs, w/ 87,000 miles.

the car runs fine when it is cold, but about 5 mins after warming up the idle gets real rough and if i try to rev it, it wont got past 1,500rpms and when i try to it sounds like its backfireing, but it wont stale. Yesterday i changed sparkplugs, a hose that hada crack in it, and the fuel filter, i also swapped afms with my bros 88. same shit.
I figured that it might have bad gas in it since its been siting for so long, so i pumped all the gas out of the car, then went to the gas station with a 5gallon gas bucket and put that into the car. Started it up after the new gas was in it, and it started off good, then idled bad and then wouldnt rev at all.

Im about to go out and check the distributor cap and rotor and make sure thats ok.

there are no engine lights turned on on the dash or check panel.
Anyone know what this could be or what i could check?

[E30godz]

yea check the ignition wires/distributer cap/rotor....also maybe run some fuel injector cleaner through it if youve got it so you can r3v a bit...

[gstuning]

Kinda sounds lika a bad water temp sensor,
if that is bad the ecu has a hizzy fit

[318driver]

That sounds like the water temp sensor might be it, because on the drive home from buying it, the fan belt broke and the car overheated. so im gonna chech it tommorow. thanks

anyone know where it might be located, cause i cant seem to find it in the haynes book.

[Charlie]

That sounds like the water temp sensor might be it, because on the drive home from buying it, the fan belt broke and the car overheated. so im gonna chech it tommorow. thanks

anyone know where it might be located, cause i cant seem to find it in the haynes book.

Whoah, whoah whoah. That "fan belt" is the V-belt for the motor, how far did you drive with it broken? That belt drives both the alternator and the water pump. With it not attached, there is no coolant circulating through the motor, if you drove on it for any length of time, you could have fubar'd many things on the motor.

-Charlie

[318driver]

right when we noticed it happened i blasted the heat and it came down quite a bit. we only drove it for about 4 mins like that, we just chanded the fan belt along with the othe 2 belts. car runs real smooth at first so i dont think that many things could have gotten messed up. im gonna look for that sensor tommorow, parts store was closed for the rest of today. thanks

[318driver]

i wasnt able to do the sensor yet, but i did notice that there was a valve that was very loose, so i tightend that and used a weather stipping sealant but it didnt solve any problems. i noticed that the hose that comes off of the intake boot has cracks in it, and a few of the other hoses look they should be changed. so does anyone know where i can find maybe a complete set of hoses for it. id like to do this first since it already should be done. thanks

[318driver]

today i finnaly got a chance to take my distibutor cap and rotor off. They are both fine, and then when i was looking under where they attach. i found a cable that had a gash in it. and the metal inside was showing and kinda of touching the engine. the cable is the timing sensor and i think im gonna change it tommorow. the last person who worked on the car had moved it and it was rubbing on the fan belt pully which put the slice in it. i hope this is the only problem. if it doesnt fix it, ill give it to my mechanic and have him take a look at it.

[318driver]

i found out what the exact name of the sensor that was sliced last night. its called a pulse sensor. im going to try and take of my brothers from his car, and see if it fits mine. does anybody know if there is another name for this sensor. because i found one that looks just like it on gprparts.com and they call it a reference sensor??? has anyone hada problem with this sensor??

[nando]

if it's the crank reference sensor you are talking about, I had a similar problem where it rubbed on one of the pulleys and shorted out, causing the engine to buck, run roughly and lose all it's power. I didn't want to spend $99 on a new one so I just reinsulated it (it had only rubbed to the ground wire) and tied it down so it couldn't rub anymore. I also checked mine with a multimeter after I "fixed" it to make sure it was in the proper range, and it was just fine.. if yours is broken all the way through though you wouldn't be able to fix it so easily.

[318driver]

yea, thats exactly what happened, we taped it today, and relocated the wire so that it was away from the sensor, and it works perfectly... tonight was the first night i got to drive my car and wow, im loving it. thanks.