Two codes after cam/header install
Two codes after cam/header install I am getting two codes, the first being PO134 which I know is O2 sensor B1-S1. The other being PO300 which is misfires. I bought two new O2 sensors and replaced B1-S1 and B2-S1 and still am throwing the same codes. I checked all the O2 sensors wires as far as I can trace them and they all look fine. I want to get this figured out before I go get the dyno tune but am stumped on what to do next. Any help!
P300 is typical for larger cams, especially if you let the car sit and idle for long periods. This can be fixed with EDIT.
Feel around all your header connections when you first start the car and the engine is still cold. Make sure you don't have any exhaust leaks. I had leaks around the AIR fittings that wreaked havoc with my O2's.
Good Luck.
Feel around all your header connections when you first start the car and the engine is still cold. Make sure you don't have any exhaust leaks. I had leaks around the AIR fittings that wreaked havoc with my O2's.
Good Luck.
Well after thinking about it some more today the light in my head finally came on. I am gonna switch o2 sensors and the o2 extensions in different combos to see if that works. I did what you suggested last night, feeling for exhaust leaks. None that I can tell.
The cam is a comp 224 581 114 lsa.
I got another suggestion that it is the plugs or wires causing the misfires and causing the o2 code to go off.
Hopefully one of these ideas helps.
The cam is a comp 224 581 114 lsa.
I got another suggestion that it is the plugs or wires causing the misfires and causing the o2 code to go off.
Hopefully one of these ideas helps.
Last edited by swandogg25; Jan 14, 2004 at 10:29 PM.
On The Tree
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I just installed a 228/228 XE-R in my m6 vette and got the P0300 codes. I drilled a 1/4" hole in the TB blade which smoothed the idle and eliminated the code. This was my only option since I do not have LS1_edit.
Found my problem. I took off the drivers side spark plug wires and borrowed a stock set of wires from a friend and put those on and problem was gone. Went and picked up 8 new NGK plugs and Taylor 8mm wires. I tested all 8 wires with an ohm meter and sure enough one was bad. Just for peace of mind I changed the plugs and good thing I did. Found two plugs that looked brand new on the drivers side. So another wire must have been bad also that I didn't catch. For the record the old plugs were MSD 8.5's that were bad.
Thanks for the input guys.
Thanks for the input guys.
Figure I would post a follow up after my first test drive.
Car was backfiring like crazy and falling on its face. We tested plug wires, coil packs, wires from coil packs to pcm and still found nothing wrong. A friend found after searching that the coil packs could be in reverse order causing this. So #7 coil pack was on #1 and vice versa. We kept them lined up the way they went back on but I guess the one got moved. And of course being a 98 the numbers were wore off on the coil packs so there was no way of telling what was what. Switched the coil packs around and all is good now.
Now the car sounds alot more healthy. Idles great, no backfires and sounds awesome.
Now to get it tuned.
Car was backfiring like crazy and falling on its face. We tested plug wires, coil packs, wires from coil packs to pcm and still found nothing wrong. A friend found after searching that the coil packs could be in reverse order causing this. So #7 coil pack was on #1 and vice versa. We kept them lined up the way they went back on but I guess the one got moved. And of course being a 98 the numbers were wore off on the coil packs so there was no way of telling what was what. Switched the coil packs around and all is good now.
Now the car sounds alot more healthy. Idles great, no backfires and sounds awesome.
Now to get it tuned.
