Engine Running Rough !!! - BMW Forum

lucky178tb · 10-05-2009, 01:45 AM

I started up the motor for the second time 2day on my 318i and drove it for about 7k's with no dramas. When I stopped at a traffic light I noticed the vehicle shaking roughly...not misfiring...but shaking. when I take it out of gear and put it in N or P it stops shaking as bad.....while i was stationery the temp climbed a little but as soon as I took off it went back to normal..I got home and noticed a bit of a hard start but with the rest of the behaviour still the same. No lights have turned on and it revs ok otherwise...just a bit of a miss when reved...... I changed the fuel pump a couple of weeks ago but that was coz the pump died on me !!! Anyone have any ideas ???

marti5 · 10-05-2009, 03:16 AM

Sounds drive train related, I would start with a fluid and filter change on the transmission, they are suppose to be done at 80,000k and every 30,000k thereafter. BMW say its lifetime which is total rubbish....

lucky178tb · 10-05-2009, 03:20 AM

Further to what happened earlier I took it out for a spin after I let it cool down and checked for anything obvious. It started ok....engaged gear ok...I took it out, drove for 500mts and then pulled over...was rough while in gear and the temp started to climb....I took off again and the temp started to drop and then went up and down again as i drove....came back home and parked. Temp has not gone all the way but my worry is the rough running....could something be broken ??? Perhaps the trans or water pump ?? any ideas anyone...Im beginning to stress out !!

lucky178tb · 10-05-2009, 03:22 AM

Hmmm....I had the transmission oil replaced and the filter changed 2000k's ago....In any case would that have an effect on the temperature fluctuation ??? Thanx for the reply

marti5 · 10-05-2009, 03:25 AM

Check out the water pump as well as the tranny service as the tranny fluid is cooled by the cooling system....so basically if the coolant system is not operating correctly the fluid in the tranny gets burnt and thickens up and is unable to circulate around the valve control body and torque converter.

marti5 · 10-05-2009, 04:19 AM

Ok youve had the tranny service, just check the fluid level to make sure its at the correct level, if thats ok then head for the waterpump, if you have a viscous coupling this could well be at fault, if you do have a V/C test it like this, roll up a newspaper, with the engine running and the fan turning stick the paper in the fan...if the fan stops, its a goner if it chews up the paper then its fine.....so then I would say go for the waterpump.....

lucky178tb · 10-05-2009, 04:55 AM

Thanks Marti....just finished doing that before I logged on again....fan clutch is ok....but there is definately some problem with the cooling sys. The bottom hose is cold so no circulation....could be thermostat....but that is 2mths old when I changed the radiator(should have changed the pump as well).....I have noticed a small water leakage behind the motor from a hose....I suspect that there could be an airlock considering that the water level was at the bottom of the expansion tank...I will wait for it to cool and then bleed the system.....I released the bleeding screw and topped up the coolant which I have to admit has stopped the rough idle !!!! Weird !!! Im not sure if Im confusing myself here or what ??? But I will wait for it to cool and then bleed the system to over-rule the airlock...if it is then its a cheap fix...if not its the thermo or the water pump....I will keep u informed...in the mean time if u think of anything else...plz lemme know.
Cheers
Lucky

marti5 · 10-05-2009, 05:26 AM

Well if the bottom hose is cold......airlock, thremo or the pump has died, I cant remember if you have a metal or plastic impeller, if yours has a plastic one then I would be saying thats your problem...anyway see how it goes with the bleed..

I did read somewhere that the e36 was fitted with the plastic version from 1992 to early 1997..

lucky178tb · 10-05-2009, 06:18 AM

Yes u r right they were fitted with plastic impeller's but when I replaced the thermo nd radiator I pulled the pump out just 2 have a feel of the bearing....nd it was one with a metal impeller...so it was probably replaced at some stage b4 I bought the car....nd it felt ok...but then again these damn things can fail at any time. However I have a gd hunch that it is indeed an airlock coz the behaviour was similar....only that I forgot that the rough idle can be caused by an airlock...once gain thanx for all the comments...will post a final verdict 2morrow as it is dark here nd is pointless to work on the car now !!!
cheers from down under !!!!

jrharman · 10-05-2009, 07:49 AM

I have had problems with my hoses after my top hose blew off..
I had to blead my system for 30 mins b4 it was running fine. I also had temp problems when i stopped my car or is was running idol...

lucky178tb · 10-06-2009, 08:14 AM

G'day,
Not the very best news 2day. started off by bleeding the system....heaps of air...thought i had cleared it all nd took it out for a spin...all went well until I brought it back nd then went for another spin...temp started to climb...then went down then climbed then just stayed up. I pulled over and had it towed to the garage. Now my question is where is the air coming from...im pretty sure the problem is air...I cant bleed it out..I spent 45mins 2day...just wouldnt stop...is that a bad sign or is that a sign that there is a leak and the system is sucking in air !!! Am a little disturbed....nd want to repair nd sell !!!! Any ideas !!!

marti5 · 10-06-2009, 10:02 AM

Try this:

How to Burp Your Car's Cooling System | eHow.com