Need Advice! Misfire

2000 Winnie, 3.8, 146,000. I bought this van in 2004 with 60,000 miles on it, and it has served me well. Recently I've been fighting a Code 305 Misfire on#5. The CEL has recently started to flash some, so i figured it was time to do something. Installed a new coil. Didn't help. Installed new plug wires and new Autolite Double Platinums. Didn't help. Someone on this forum (12 Once?) suggested to remove the EGR vacumn line and plug it as a temporary thing. BOY!, what a difference that made!. Van seems to running Perfect! So where do I go from here. I read the codes tonight and got a 401. Understandable with the hose being Plugged. Code 161, Probably also related to plugged hose. But no 305. I did replace the DPFE several years ago to clear a 401 Code. The original metal one was replaced with a plastic one which did not last and was replaced under warranty with another metal one, which is still on the van. To my knowledge the isolator haven't been changed and EGR ports have never been cleaned. Thats probably what I need to do, just would like some other opinions. Thanks Folks

Clean EGR ports for sure. If they get plugged up it can definitely cause a misfire just like you are experiencing.

I like to do things in order of cost, so I try and start with "free". If the grommets are green on the lower plenum ("isolator") bolts, you're all set there. If not, just buy/order the grommets; costs about $17 for the set of 8. Then just cut off the black ones and slide the green ones on. Buying brand new bolts at the dealer is not necessary. You might change the port seals (plenum gaskets) if that hasn't been done before. Again, get the felpro ones for about $20 for the complete set.

Thanks for your reply Scubacat. I'm sure thats what I need to do.Where do you get just the green grommets at? I was thinking of buying the Dorman 615-177 kit from Amazon.com for $77.00. Also how long can I drive the van with the hose plugged before damaging something else. Thanks again

Advance auto carries them sometimes. Search for FelPro part # ES72204. (Their stock picture is wrong and they never fix it. It IS the correct part - I ordered it myself.)

I don't think EGR being plugged will damage the van persay but you'll lose gas mileage. It could eventually wear out the catalytic converters too.

Just pull off the plastic intake plenum and clean out those ports. Swap out the grommets and port seals and you should be good to go.


Green Grommets

http://www.rockauto.com/catalog/raframecatalog.php?carcode=1362844&parttype=13338

Port seals:

http://www.rockauto.com/catalog/raframecatalog.php?carcode=1362844&parttype=10394

Thanks again Scubacat. Do I need to worry about changing the Valve Cover. I've read a lot on this forum about doing that.

I think Advance Auto has the inlet bolts the cheapest I've seen. I would say that, Yes... the green-grommet bolts are much improved over the original black rubber one ...But, they are not perfect, and they will finally fail after giving much service. I'm about to have to replace the bolts on my '99 ... the green ones in-place have been there well over 100K miles, I would guess.

Well I had some success. Got the seals and green grommets and took her apart. I was happly after I got the Plenum off to see that I already had the green grommets on the isolator bolts. Left them alone. Very little oil anywhere. #5 port was spotless. The rest of them were plugged really bad! Got the dental pick out and the shop vac and cleaned those ports out. Plugged in the EGR Hose that I had unplugged. Fired her up and it's running really well. No stumble/miss/hesitation or anything! Still got a code 161 which I believe is the lower Oxygen sensor?? Also, Why was i getting a misfire on #5 when that port was spotless? Doesn't make any sense to me. Was it spotless because it was't firing? Thanks for all your help

Why was i getting a misfire on #5 when that port was spotless? Doesn't make any sense to me. Was it spotless because it was't firing? Thanks for all your help

You get a missfire on the cylinder with the clean port because it gets a larger volume of EGR flow due to the other ports being pluged. The extra EGR on the clean port upsets the fuel mixture and "puts the fire out"

My misfire was due to fuel injector

http://www.automotiveforums.com/vbulletin/showpost.php?p=7036543&postcount=25

You get a missfire on the cylinder with the clean port because it gets a larger volume of EGR flow due to the other ports being pluged. The extra EGR on the clean port upsets the fuel mixture and "puts the fire out"

That's exactly right. Usually the clean ports are the ones that report the misfire.

The green grommets may yet fail after a while but if they looked fine, as you said, I'd leave them alone.

After driving around town for the last couple of week, I finally got it out on the highway this past weekend. Really seems to be running really well, Plus, I got right at 22 mpg on a short 250 mile round trip. I'll take that anyday. Cheers!!