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chrislambing
04-15-2009, 10:30 PM
I have an 01 RT with 108k on it, I have a few small mods including flowtech stainless headers, magnaflow exhaust, CAI, it started running extremely rough and sometimes would not stay running. I scanned it and it told me there was a random multiple misfire, and cylinders 3,5,7 were misfiring, also a low voltage on sensor 1 bank 1's o2 sensor. I replaced the o2 sensor, changed plugs, wires, distributor cap and rotor, coil, did a fuel pressure check and put a fuel treatment in the gas, after all that it still runs like crap, I feel it misfiring at mid-high rpms, and a big loss of power. Another thing is that every once in a while it will run better than it ever has, it will run smooth and it will have excellent acceleration, but 2 mins later it will run like crap again. any help would be much appreciated!!!

SB440R/T
04-16-2009, 12:53 AM
Try and clean the IAC sensor. Pull off the TB and clean where it goes in also. Could be simple build up.

Five9Dak
04-16-2009, 02:17 PM
Keep scanning it periodically, don't clear the codes, and see if anything else pops up.

chrislambing
04-17-2009, 12:58 AM
thanks, I have already pulled the tb off and cleaned it with some chemtool, also checked the iat sensor and it seems to be clean, i have it in the shop at the moment, so we'll see how much it will cost me

SB440R/T
04-17-2009, 10:40 AM
Hmm. You never pulled off the distributor right?

chrislambing
04-17-2009, 10:26 PM
Yeah, I pulled the cap and rotor and replaced with OEM parts I thought at first i accidently crossed some wires on it but i double and triple checked and they are all on there correct. I have also replaced the coil and the wire going from the coil to the cap.

chrislambing
04-21-2009, 12:21 AM
what happened the downstrean o2 sensor on the first bank the tip broke off in the cat bc the insides of the cat were loose, so the mechanic says i need a whole new Y pipe assembly he quoted me 750 plus labor, anybody know of anyone cheaper?? or other suggestions on what to do instead??? Thanks.

ddrango
04-21-2009, 12:38 AM
what happened the downstream o2 sensor on the first bank the tip broke off in the cat bc the insides of the cat were loose, so the mechanic says i need a whole new Y pipe assembly he quoted me 750 plus labor, anybody know of anyone cheaper?? or other suggestions on what to do instead??? Thanks.

Damn that's a rip off if I'm reading correctly. Wish you lived closed I'd fix that for you. You need a new o2 sensor, magnaflow high-flow cat and an exhaust shop to make you the new y-pipe. Now is the trim for a whole new exhaust, look up exhaust pieces/kits on www.summitracing.com if you want. They would just be bolted on.

EDIT: Never mind, all you need is a new y-pipe with the 02 sensor fitting on them (one on each side) The factory exhaust has one pre-cat on each down pipe, then one cat after the y-pipe. All that's needed is one cat for emissions, and the way the 01'+ trucks run is just with monitoring the exhaust gases, not if the cat is there or not.

chrislambing
04-24-2009, 12:33 AM
I got my new o2 sensor in and it is running awesome, im going to the exhaust shop next week to have the cats removed and a new y pipe made, will I have any obd2 problems???

SB440R/T
04-24-2009, 12:19 PM
You can get the Y pipe off of Summit to make it easy. Nice peice I have it on my truck.

http://store.summitracing.com/partdetail.asp?autofilter=1&part=MPE-10778&N=700+-218805+115&autoview=sku

What you would need to have made is the down pipes. But might be cheaper to go with the Spintech Y pipe that is made for whatever you have. I think they are 250 or something with nice mandrel bends. An Exhaust shop can't give you that.

chrislambing
04-30-2009, 10:22 PM
I took the truck to a local exhaust shop, he cut out the cats and welded straight pipes in, and wow, what a difference in power, he said the cats were some of the worse he's ever seen they were completely clogged and had started to weld themselves shut, no more misfires, runs amazing, gained some hp, sounds better, couldnt ask for anything else.