Help Please!! 03 SE pulled out code P-0300B random misfires.
 

There are many things that could cause your problem. First off, your car will not rev higher than about 4k RPM in park or neutral. That is hard on the engine, so a rev limiter is programmed into the computer to prevent the engine from running any faster than that without a load.

Can your provide the codes that go with your fuel problem? Are you losing any coolant? Start by replacing your plugs and wires, and possibly post pictures of the old plugs once you pull them out. Check for rust or corrosion on the coil terminals, and test the coil per the procedure in techinfo

http://www.bonnevilleclub.com/forum/...e=article&k=33

That will be a good start. Then post back with your findings.

Unfortunately there are no codes pending or hard for the fuel issue. I got that info. off the data stream I ran and recorded 2 separate tests. Data stream info is as follows: STFT bank 1 sensor 1 =10.9% ; STFT bank 1 sensor 2 = 99.2%; RPM=847; temp= 185°; spark adv.=22°; Fuel system status bank 1= closed; Fuel system status bank 2=disabled.
This one has 3 double coils controlling 2 cyl. each, and with one whole fuel bank showing disabled and a random misfire instead of a specific 1 or 2 cyl. misfire I am a little buffaloed. Also a week ago found some coolant on the transmission and seemed like it ran down the rear drivers side corner of the intake or plenum area, but cleaned it off in that area with some engine cleaner and figured I would just keep a eye on it and it's still dry. At that time it was about -5° below zero with a bad wind so I figured maybe just a freak thing. No running problems after that for a whole week, and I work 38 miles away. It has been about 500 miles or so since that happend. I heard these 3800's have intake issues, what are they and how can I tell? :?:

Information on the intake problem can be found here, in techinfo.
http://www.bonnevilleclub.com/forum/...e=article&k=38

A search of the forum will provide you with many threads regarding it. Is the coolant in your expansion tank dropping?

Checking the coils is a good troubleshooting process. While it may not be the main cause of what your are experiencing, it can be contributory. If one coil has a problem, you would have the one or two cylinder misfire. If more than one, which is rare, but not unheard of, you'll have more misfires. The coil terminals have been known to rust.

Bank one being closed indicates that the system is in closed loop. We'll have to wait for someone a bit more familiar with that part of the scan tools on if there is a sensor for that for bank 2, or if it just uses one. Do you have reading for STFT at higher RPMs? What does the MAF and O2 sensors show? What about fuel pressure? Have you tested that? Checking the condition of the plugs can provide a lot of information also.

We can head off in several different directions, here but let's try to follow a bit more of a methodical process.

Forget bank 2. That's the O2 behind the CAT. It has nothing to do with fueling or running.

Look at your injector pulsewidth or duty cycle to verify all 6 injectors are firing.

Went out agian and scanned it and did a thorough check on the intake and plenum and found an external leak on the back side of the plenum on the firewall drivers end of the plenum. Scanner shows misfires on 3 and 6, which are on the same coil, coil tested good but changed it anyway, leak may have caused these to cylinder to get wet. I can't get the plug wires off those two cylinders or any others for that matter, to change the plugs and look at them. Any tricks to getting these off? Do you think this is safe to drive to repair shop like this? These 2 cylinders are missing on every rev.. Thanks, cb :roll:

Twist the boots back and forth. They'll break loose. I'll be curious to see what all 6 plugs look like. Put them in order when you pull them, or mark them with cylinder numbers as they come out. When you get them out, check the resistance of each plug wire. Post your numbers here.

So is the external leak related to the fuel banks being shut down? :?

No, Mac. It's not. And the fuel isn't shut down either. Read the replies above.