engine codes with rough idle

[uuc328]

i drive a 97 328 w/ 128k miles.
last week my car began to idle rough, shake violently, hesitate on acceleration and it feels like it might be miss firing when the car is warm. at a cold start the car idles and drives normal but in less than a mile or until it heats up all symptoms from above are present.

these are the codes that were pulled from AutoZone
P1188
P1189
P0170
P0170

i should add that right before the trouble began i attempted to clean the HFM and pre cat o2 sensors. using 91% isopropol alcohol on the HFM and TB cleaner on the o2 sensors.

after cleaning these the car drove great for about 15 min but then the CEL light came on and problems began.

since then i have tried 2 seperate HFM's one from the dealer and one from a known working car and have replaced the 2 o2 sensors that i cleaned with new Bosch replacements but the problem persists.

additionally i have pulled the plugs to check for fouling and have tested each coil pack and all are within the .4 - .8 ohm range.

can someone please help, i am running out of ideas

[aeryk7]

Probably your HFM , but the p0170 code i believe has something to do with fuel trim malfunction. I wouldnt recommend spraying any kind of cleaner through your HFM . All in all your HFM might have gone bad see if you can swap one out with a buddy to find out.

[uuc328]

All in all your HFM might have gone bad see if you can swap one out with a buddy to find out.

i have tried 2 seperate HFM's one from the dealer and one from a known working car but the problem presists.

that was my first guess but as you can see i have already tried this. i do agree the HFM sould probably be left alone and i am not sure what possessed me to try and clean it

[uuc328]

can someone please help me with this?!

My most recent repair attempt was to reflash my ECU back to the stock SW but the problem still persists.

[hinzm3]

bump

[hinzm3]

nobody else has any ideas?

[uuc328]

I thought my problem might be vacuum related so I installed the vac gauge this morning. It read a steady 22 in.Hg at idle. Pretty sure this is normal, can someone please verify? couldnt find the range in the Bentley, maybe i missed it.

Now im leaning towards a faulty ignition coil. Anyone have one or a set they will let go of?

BTW - Ray, thnx for the bump.

[uuc328]

Ok, ive got a set of coils on the way but now im not so sure that they are the problem .
I spoke with a BMW mech today and his first guess was the pressure regulating valve . number 2 in link
Has anyone replaced theirs and if so what were the symptoms?

[hinzm3]

Thats the one I checked vac to and everything seemed to be hooked up fine. If you want to we can swap it out with my car and test it. Should only take a few mins

[uuc328]

the vent pipe, # 1 in the pic had a crack in it and was leaking a little oil. it was replaced on wed but nothing changed

[uuc328]

teh car is fixed and back on the road.
Ray i appreciate your help on Sat.

now, on to the next project

[speedngreedy]

so what ended up being the problem?

[uuc328]

unfortunately im not 100% sure what fixed it.
i checked and changed so many things that day.
to name a few possibilties
all the twist off wiring connections were opened and sprayed with electrical cleaner, the o2 sensors were reseated at their connections, the coil ground straps were cleaned and tightened and a few more vac lines were replaced just for piece of mind.

[hinzm3]

your car is the devil.

[uuc328]

el diablo blanco