5.7 hemi idle and backfire

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i think you are correct AJ but im not familiar with how to reset the ecu to lean it up ive never fooled with that since i had it reflashed
 
You could honestly lean it out and at the least call Hotwire and explain that's it's running rich. However without a wideband O2 sensor it's hard to determine where it's rich.

Riddler
 
Riddler i have been looking at the two o2 sensors i took out of the car and the one that was failing has just a small amount of blackening in one area around one of the inlet holes the other one is about the same. if i understand afr correctly if the motor was running too rich the blackening would be very heavy. the moto has less than 300 miles on it and im sorta thinking the sensor may have just gone bad. what do you think?
 
Are you running throttle by potentiometer, or actual cable and letting the transducers figure out what's going on by putting the throttle position sensor into the mix as post-information to the ECM?
 
Two co-incidental failures at the same time is highly unlikely.
I would be tempted to bolt those O2s back in and blame the problem on the plugs.You did replace the plugs too, right, as you said you would? I have seen it many times where sooted plugs leak away the spark and do other tricks on a running engine. Anyway it's only a few minutes to find out.But if you only replaced those O2s then skip over this paragraph.
COPs don't have the power characteristics to deal with sooted plugs. Furthermore COPS are usually designed for/around specific specialty plugs.They often have a hard time dealing with non-specialty plugs, with their higher voltage requirement for spark initiation..
 
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while keeping on the subject of o2 sensors , from what i have heard that all mopars like oem sensors and that we should not use aftermarket sensors , no only have i heard this but a friend experienced it first hand and with a hemi , was running ok , then like crap , changed o2 sensors with aftermarket, ran ok for a short while , then back to crap , scratched head for while , changed computer , no change , finally to it to shop , found out aftermarket o2 sensor wasnt sending the right amount of voltage to computer , and he installed new oem o2 sensors and the thing runs spot on . so any feedback to this would be great. i am getting ready to buy o2 sensors does anyone know if you buy the down stream or up stream sensor if you are installing in the header and does the header side matter or do you install one in both ? thanks ed aka dartman 440
 
The error codes you had listed overheating and such on the o2 sensors. I can't recall exactly. I'm guessing the o2 sensors prolly look fine but are fouled up. With an engine with 300 miles, I'm guessing it's a lot of short trips. I'm hoping your doing some good break in procedures. I believe your issue was with one o2 sensor on the side that has the fouled plugs. The computer prolly went to open loop and dumped fuel thinking the AFR was out of wack..

If it's working then drive the **** out it. It the o2 continue to foul, then look more into the issue.

@dartman 440 I alwsys use OEM o2 sensors. Same reason....there pretty much the best. But a Bosch/Denso will work as well as that's who makes the OEM's. On the swap the downstream o2 sensors are not needed. I'm going to be using upper O2's on my TTI headers.

Riddler
 
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