318i rough idle - BMW Forum

rampage601 · 10-18-2011, 11:40 AM

i have a 1994 318i just replaced the trans (5spd) fuel pump and the air filter is bad so i took it out it has a very rough idle and there is no check engine light..i havent checked the cat converter yet but could it be anything right in front of my face i may be missing..it did sit up for 3 years so could it just be a temporary thing?

Jack Dabsy · 10-18-2011, 01:14 PM

You need an air-filter in there mate...
You probably have a dirty MAF too !

rampage601 · 10-18-2011, 01:54 PM

Oh yes I know it looks horrible haven't checked the maf but I'm not doubting that's part of it
But NOW it wont crank..it tries but wont go through with it..

Jack Dabsy · 10-19-2011, 02:31 PM

Pull the spark-plugs and explain any differences...

rampage601 · 10-20-2011, 06:53 AM

Changed spark plugs now its back to the erratic idle between 900-1700 rpms.it runs great until you down shift to come to a stop then it stalls but cranks right back up. If I don't try to put it in gear thereafter it will sit there with a crazy idle but as soon as I put it in gear I better go, or else.

Jack Dabsy · 10-20-2011, 02:45 PM

ICV (Idle Control-Valve) is dirty my friend... This controls the air-flow at tick-over !!
Why not clean the Throttle-Body while you're having fun !!

rampage601 · 10-20-2011, 03:33 PM

ran sea foam through the engine
no change
noticed that it has a dead miss
did a compression check
190 on 1st and 4th
175 on 2nd and 3rd
also
brand new plugs i bought last night
are BLACK!

Jack Dabsy · 10-21-2011, 02:15 PM

Black plugs (If correct type) = Rich mixture... Run it without air-filter and notice differences...

rampage601 · 10-21-2011, 06:59 PM

i think there is a vacuum leak and i cant find a diagram for the lines to see if anything is missing..still gonna check the o2 sensor and everything along with it that would cause it to be running so rich..input needed if possible!

Jack Dabsy · 10-22-2011, 10:33 AM

Just check all the pipework my friend, remove any offending pipes and duct-tape them as a temp fix...

rampage601 · 10-22-2011, 11:47 AM

ok we found the vacuum leak
the idle is alot better its staying around 11-1300
still loopy and smoking grey smoke i believe
i would be sure if the wind would stop blowing
while driving it will idle fine at times and then sometimes it will die
BUT always cranks back up
i think its the best running car ive had..as long as its not sitting still ahaha
we still love it not giving up on it yet

Jack Dabsy · 10-23-2011, 06:11 AM

Where was the leak, dude?

rampage601 · 10-23-2011, 12:01 PM

the vacuum hose with the check valve..still not really sure if we hooked it back up right cause my dad looked at a picture i googled of that part of the diagram and were missing the t piece and he's not sure if he has the check valve turned the right way

Jack Dabsy · 10-24-2011, 02:53 PM

Check-valve? Sensor or one-way?

rampage601 · 10-26-2011, 12:26 PM

honestly no idea..i can post a picture of it if that would help
also it threw me a code finally
i think it was 1222
which im getting 3 different meanings for..
tps switch a or b low input
and o2 sensor control???
never heard of o2 sensor control but this is my first bimmer..