Hi every one. 2003 v6 3.0 VIN M61254 I am have a big problem with my car i am geting Restricted Performance and Engine Light and missfire's P0300, P0301, P0303, P0305, AND P1313 looks like the whole right side of the car. can all 3 coils go bad on one side at one time. the only other think i can think about if it is not the coils is the ECM is goin bad, or a wiring or pin's any one have any problem like this any help would be great thank u all.

 

What mileage has it done?

What do you know about the care it has had from former owners?

Plenty of info about misfires via google

Read threads by BugDoc about misfires and changing coils, plugs etc

Reasonably cheap to do but you will get more or worse problems if done wrong

It's far more likely to be coils/plugs than PCM(ECM). But do some reading, check for air leaks (especially the various elbows - read old threads here) and oil in plug wells. Don't even think it could be the PCM at this stage - go for the simple and cheap stuff.

Misfires can quickly damage the cats (hugely expensive) so try not to drive the car.

Check wiring diagrams (get JTIS if you haven't already) in case there's something common to cyls 1,3,5. Or anything mechanical (for air flow) unique to that side.

If you know how, look at O2 waveforms although with so many errors I'd do that only briefly before fixing the cheap stuff.

Has any work been done recently that may be to blame?

 

Also, make sure your CKP is good, although as the misfires are all on one bank it's not so likely to be the CKP.

 

jagv8 the car has 93000k no work done to it.

will i have some very bad news i just but new coils and plugs and seal's a whole tune up and problem is still there. $700 in and no fix. i just found out that it was the cats the whole time. had a shop do a heat test on the cat's and the inlet temp was like 700F and out was 200F to must back pressure. so i am looking at about $2000-$2500 form the dealer for new cat's and O2's. this suck's

the thing that kills me no O2's codes or any thing close to it just misfire code on one bank i have never heard of that.

 

With so many misfires, what O2 codes would you expect? Was it running closed loop on both banks? What were the readiness monitors saying?

What were the O2 waveforms like? What are they like now you've changed coils/plugs?

 

In some parts (all?) of the USA, there is an 8 year warranty imposed on the manufacturer for various emissions parts. I understand that includes cats. You would do well to find out (probably NOT from the dealer!) whether that applies to your car.

 

Is there not a way to do a cat delete?

 

What about fuel?I've seen fuel rails get restricted.that'll make all three cylinders miss.

 

Dude. What the hell? The dealer is the BEST place to find out if an 8/80 component is covered, or applied to his VIN. I can check in 2 seconds from this here chair, if he'd like to know! Why the anti-dealer sentiment? I don't think you know what you are talking about here.

 

Yeah, at 93k, nothing is covered. The 8/80 is 8 years or 80,000 miles on CERTAIN emission components, and the catalysts are covered IF they were NOT damaged by an ignition or fueling misfire, or fuel saturation.

 

poboyblues - you should know by now that I'm not at all anti-dealer but am anti-useless-dealer. I'd get you to do work or diagnosis but not some of the dealers whose work and quotes are mentioned on here. If he can find a good dealer, great.

He says 93000k which ought to be km and thus well under 80000 miles so may well be in warranty - but it could be a typo.

Naturally cats are not covered in the situations you list.

Maybe you could tell him what you think about those cat temps?

And maybe tell him which ideas from my original reply to him were worth doing and in what order? Or better ones, if I missed them.

 

Hopefully they took a look at the fuel rail while they had the manifold off. They are only accessible with the intake off. Hopefully they did the pcv valve while they were in there too.

The temp difference before and after the catalyst does make it sound like it is clogged. I am getting the "Catalyst functioning below min threshold" code on mine and there is almost zero difference before and after.

I'm still looking for more reasonably priced CATs. I have an '02 so ours are different. But I think I saw some with 5yr/50k mile warranty for the '03 for not too much. If the setup is similar, changing them out is only a 3-4 bolt job.

 

The cat temps are a giveaway for sure. They need to be replaced. Now, as to what caused the meltdown.......coils would be my first guess.

I think you pretty much nailed it with your post, no need to repeat.

 

just an update my car is working now. installed new cat's on both side's misfire's are gone. the car is working good for now. but the trans is a different thing i have a little trans leak and the lurch an squawk form the trans.

Has any one used Pentosin ATF 1 for their trans? i seen a lot of bmw owners use it.

I think the problems we have with our trans is the fluid and should be changed every
40,000 -50,000 miles.