Misfire detected random or unknown cylinder
 

Hi,

I have a 1997 318ti and I bought the Bavarian Fault Code Reader/Reset tool
I keep on getting these three faults; “3E” Misfire detected, random or unknown cylinder,
“33” Misfire detected, Cyl#2 (I also got code 34 Misfire detected, Cyl#3) last time, and this one comes on all by its self 5E EVAP large leak.
Question, are these critical errors if so what can I do to fix them?

Thanks
Bill

Sounds like a leak in your intake tract. Check your connections and the rubber boots. Spray a light mist of water or carb/choke cleaner around the joints, when the car stalls you found your problem.

I was getting random misfire codes, as well as for cylinders 2&4. My car had about 90k miles at the time. Replaced spark-plug wires. Fixed.

same with me, I was getting random misfire codes, as well. I changed the spark plugs (NGK) and problem gone. I just had the car inspected 10/13/06 and it passed, no codes at all. I changed the plugs like 7 months ago.

Two things to check:

1. As noted before, check ignition system componets. If you haven't replaced the plugs in awhile, they should be replaced anyways. Also check the condition of your plug wires, if they show signs of cracking and have never been replaced this could be a source of the misfires.

2. The large leak in EVAP is most likely caused by a loose or missing gas cap, but the fault could also be set by cracked or broken hose on the intake tract as noted in a previous post.

cheers

Thanks Guys for the tips. I will try new wires and plugs.
And double check the intake tract. I'll keep you posted.

Bill.

Is there any resolve to this issue?

Sorry I took so long to reply I wanted to make sure the problem was fixed.

First let me run through what I’ve done.

I was getting the “Check Engine” light and I would read the codes, it stated that I had misfire on some of my cylinders and it would also report that I had random misfires. So I checked my ignition components, decided to replace the sparkplug wires and the Coil, about mid November. Well just last week the light came back on, so I check the codes again and this time I got the same codes plus a bunch more. Well I’ve been having trouble starting the car on very cold mornings, about 5-10 degrees F, so between both problems I replaced the battery last weekend with the correct size (Type 91 “Batteries Plus” carries the correct size). Now I’ll wait and see if the engine light comes back on.

I’ll keep you posted.

Regards

Bill

heres a question. i have a 97 318ti and love it, but it has a misfire. i have replaced the plugs, wires, and coil. i have also had my injectors cleaned, i sent them to linder fuel injectors and they tested them and everything. they said they are ok. i still have the misfire. i seams to be worst when it is cold out. it misses hard core for like 1-3 min than runs fine! i can still feel it a little when it is warm but not that much. any ideas?

dry and cracked intake boot.

Hi Cheeesman,

I haven't found the problem yet. I did the same as you but I didn't have my injectors cleaned, I thinking it might be a computer issue, I still have the same cold weater issues. I'm thinking about taking it into a BMW dealer and see if they have any ideas. I keep you posted.

Bill

what is the easiest way to fix a cracked intake boot? replacing it seems like a pain, is there something i can spray on it or somethign? gheto, i know.. .. but by no means is my car a show car.. :tongue:

duct tape, that's what I used before I replaced the hose

haha... awesome.. i was thinking of like a spray on glue really.. but hell.. my car is ready to fall apart at 120k miles.. ill do anything to keep it going.. maybe ill post pictures when im done with my "mod" :cool:

if the rubber is brittle enough, gluing the two pieces together won't help since the boot could just rip again right next to where you glued it, take it from a Vermonter, we use duct tape for everything, lol :biggrin: