Service Engine Light

I have 98 Plymoth Voyager 3.0. Have had trouble with the a/c just forgetting about that for now due to the fact it wont pass emissions test. After performing the emissions test and failing and still having to pay 40 bucks to find out the only code coming up was Multiple Cylilnder Mis-fire. Had the cam shaft seals replaced about 2 months ago,was pouring out oil. The plugs and the wires are only ten months old. The car runs fine, except....
when I first back it up out of the garage in the morning it stutters as if the brakes are sticking if you follow me., well that is what if feels like. I replaced the bulb in the dash for the service engine light and it eventually came back on and started reading codes. First code I think I got was 11 or 12, hard to read codes and drive on the freeway... Then I thought I got a 3, 5 , 7 , then 12 and maybe a 5, 5, and the light remains on. The light came on for a few days and now it wont come on to do the test again. My question is does any one know what this problem could be and why the light comes on and goes off. The mis-fire code P0300 doesnt give me a cylinder to check or anything... dont know where to start. Also the exhaust has a strong smell to it, not the rotten egg smell you would get with a cat...could o-2 sensor be going out...I have been running Reg. Unleaded in it, could that have anything to do with it? hate to have to replace something if not necessary. Really the van runs great but did notice a slight difference while it was reading one of the codes, I just cant get the light to come back on to do the test, sounds crazy and I know Autozone etc... will read for free. Any input would help and would be appreciated.

well, i'm not going for the check engine light codes since this is OBD II...

is that the only code that came from the scanner? autozone read it for free? check engine light staying on constantly?

well, a cyl misfire means you'll have to recheck all those wires/spark plugs... eventhough, they're 10 months old... ohm test for continuity/resistance on the wires...

actually removing the plugs to see if they're not oil-fouled from that seal leak you had earlier is also noted...

dunno if that's a cap-rotor design or a distributorless ignition system... they'll be the next thing on the list.

check plugs/wires 1st...

Thanks for the reply, Got pulled over last night by a police officer telling me my inspection sticker was out... explained the situation and was let off with a warning...this morning i drove the van and the service engine light came back on and it started reading codes as I was driving as it did before, and it read the code "43" according to my manual (chilton) it's a miss fire in the #5 or #6 cylinder. Good place to start so I think those plug wires and plug will all get changed out. Thanks so much for your time.

p0300 mutiple mis-fire. and as you did get code 43 it can be mis fire from cyl 1-6.possible injector problem,the wires that you put on were they good set or cheap ones? and do as ricebike suggested and recheck the plugs/wires

Checked the plug wires and had some readings lower than what the manual suggested, 4.4 on my ohm meter,should be 10.4 that was on the #2 wire and #6 read NADA ZILCH the wires were put on by a local shop, I just purchased borg/warner hope this does the trick, this car is hot to the touch even on a short trip, I'm no mechanic that is for sure but dont mind getn dirty and getting the job done, is this related to the misfire possibly, I have replaced thermostat, water pump, and coolant temp sensor, hoses,my guess is it is. When I changed the coolant sensor my fans started working again...that saved me quite a bit of money, Keep you posted...and thanks again for all your help and good advice Thanks Earlyrizr and Ricebike....

oh man! u found the problem!!! were the wires purchased by you? most aftermarket sets/ the decent ones, have limited lifetime warranties...

so you shouldn't spend more on another wire set/ sometimes it's a manufacturer's defect or installer error, but w/ the warranty, u r covered for a free exchange set... don't pull the plugs... see if the wire problem would solve it 1st... hopefully the mech used a dab of anti-seize on the threads of the plugs to keep them from stripping in the future :P

and used a bit of silicone lube on the plug ends to make removal/installation of the wires easier!

thank u for the update!

Well thanks to you guys I might be on the right track...I purchased the car a few months ago, June I believe. Past owner took to local shop and had a tune up done found the reciept in the glove box that is how I know it had been done 10 months ago. I think the local shop "should" have put in a decent set of plug and wires, they werent top of the line but the price exowner paid sure was. Going to put on 1,3,5 plug wires in the AM. Glad I am mechanically inclined and I am thankful for this website also and many other should be too, the help and amount of money saved by the adverage Jack or Jill (in my case) and the goodwill towards others in need is a good thing. Only in America. I'll keep you posted on my progress and THANKS