Scan Codes P1189, 1188
 

I keep getting the following codes when my check engine light comes on: P1189 and P1188. I have changed the following parts: oil, oil filter, air filter (from stock to K&N), fuel filter, O2 Sensors pre cat, and spark plugs. The 323I has 98,000km. The car runs fine, no hesitation or rough idle. Every time I clear the codes, the check engine light comes on again but never at the same interval.

Anyone have any suggestions?

Thanks

Can you get ahold of another code scanner? Some times I use my onboard scan and then use my Peake scanner. Just to make sure.

codes
 

I did and it gave the same codes. It was a snap-on tools scanner. any suggestions?

So what do the codes mean. Don't make us look it up. :)

1188 - fuel control bank 1 sensor 1
1189 - fuel control bank 2 sensor 1

Where are these sensors?

I did some searching. The code is from the precat O2 sensors but not necessarily because the sensor is bad. Most likely it is a problem in fuel delivery.

You've already replaced the fuel filter. Other repairs I've seen were MAF sensor and Cyclone Separator or general vacuum problem.

http://tech.bentleypublishers.com/thread.jspa?forumID=69&threadID=2917&messageID=943 0#9430

Blindly replacing the cyclone separator would not be a bad idea, they tend to fail at 70-100k. I would test the MAF and check for vac leaks. You can probably find more info on the web. I only spent about 10 minutes searching.

Re: Scan Codes P1189, 1188
 

I had the same codes on my 96 328i. Corrected them by swapping the O2 connections on top of the engine. Seems as if i connected them wrong when i changed out the old O2 sensors.

thanks for all you input and help. It ended up being the crankcase breather valve and hose.

Joe

Goes to show what we know. LOL

Wait..

The crank case breather valve IS the cyclone separator.

I wanted to add a footnote to this thread as I spent almost 6 months fighting P1188 and P1189 codes.

Not until I stumbled upon Acegolf's note about swapping the O2 leads did I find a fix. Co-incidentally, we both have 1996 328i's.

I just want to share this knowledge with the group as I spent hundreds of dollars replacing parts that probably needed replacing after 195k miles, but in the end, the simplest answer was the one thing that made the difference.