Help My Ho! Missfires and other drama.

[03Sleepr]

I've changed plugs (NGK TR55) Wires (Taylor ThunderVolt 8.2mm) coils (D576) and a new battery and I am still throwing p0300 and p0131. plugs were fouled when I pulled them, it looked to be all carbon fouling but I sprayed a couple with PBlaster so I couldn't really tell if they were oil fouled.

I'm having random missfires and backfiring out of my exhaust, SES lights also blinks sometimes. All of this started when I quit driving in early December, it ran fine prior to that except I was getting ~16mpg on a good day. I've tried my stock wires and coils to no avail, also tried the new coils and wires before I changed plugs.

I'm kinda at a loss as to what I need to do since I don't want to drop the money on injectors if I don't need them

My mileage went to hell after installing my headers, can someone provide me with a link for the wire extension for the o2 sensor? plan on calling Ben at WOT-TECH sometime to figure out what I can do for a tune too.

Can anyone "Read" my plugs and make sure I'm not missing anything?







This one was sprayed with PB.






This is one of the new TR55's after about an hour of run time total

[Mike The Canadian]

Is your o2 plugged in?

It sounds like there may be an exhaust leak throwing off the o2 readings?
I've had a hell of a terrible time keeping headers sealed (yay for daily driving between temperatures of -30 and + 30!)...

I've eaten a CAT due to a combination of exhaust and intake leaks.
The atmospheric air getting in (or exhaust gasses escaping) can throw your fuel trims way-off.

I know Paul said at one point my car was adding something along the lines of 60% or something crazy like that due to this leak.

Ripped the headers apart, re-sealed them and called it good!

[MMGT1]

I'm betting an exhaust leak before the O2. O2 reading free air will make it think its lean and add fuel to try and compensate, result... exactly what you have there

[03Sleepr]

yes o2 is plugged in, but instead of using the wire extension kit I cut and soldered the wires, so I'm sure that effed my readings.

60%? wow.. it doesn't sound like I have any leaks under-hood but knowing how much trouble I've had with these headers it wouldn't surprise me. I'll check them out today.

[MMGT1]

Solder should not be used on an O2 sensor, your right. Never cut the wires on O2 sensors that come with adapters, because, interestingly, these types of sensors "breathe" through the wires. Every O2 sensor works by comparing exhaust gas to outside air. As a result, cutting the wires and soldering them clogs that minute pathway and renders the sensor useless. Well not every one bud, the titania sensor, unlike the zirconia sensor, does not require a reference sample of atmospheric air to operate properly. This makes the sensor assembly easier to design against water contamination. While most automotive sensors are submersible, zirconia-based sensors require a very small supply of reference air from the atmosphere. In theory, the sensor wire harness and connector are sealed. Air that leaches through the wire harness to the sensor is assumed to come from an open point in the harness - usually the ECU which is housed in an enclosed space like the trunk or vehicle interior.

[xXManwhoreXx]

Have the gap on the plugs changed?