misfire because of a p0100 code?
Thread Starter
Staging Lane
Joined: Feb 2008
Posts: 69
Likes: 0
misfire because of a p0100 code? ok so I just installed my headers last week..got the rest of the exhaust componets on, everything back together (except I left my rear 02 sensors off...im going to get simulators) and now it really feels like my car is misfiring..especially at low rpm with high throttle. The car never did this before and ran great before I did this header swap. So once I had the headers on and drove it around and found out it felt like it was misfiring, I just assumed that either one of the spark plug wires got burnt through or I has accedently switched 2 of them up. So i went and bought boot protectors and new spark plug wires and installed them. All new wires with heat boots on the end of them. I am pretty sure that I have them all in the right spot because I did it one at a time and its kinda hard not to being as they are all diffrent lenths. So im about 90% sure its not the wires or the wiring order. I took my car to autozone to have them run the code check, and i assumed it was going to bring up a misfire on whatever cylinder was having the problem and of course my rear O2's. Well turns out, neither of those that I expected came up, and instead I was getting a P0100 - Mass Air Flow (MAF) Circuit Malfunction code. WTF? Would fixing this likely solve my misfiring problem? and maybe it isnt even misfiring being as it didnt throw a code for it...but it also didnt throw the O2 codes which kinda makes me think i just havent driven it around enough for it to code. What do you guys think?
On The Tree
Joined: Mar 2007
Posts: 198
Likes: 0
From: Tacoma, WA
ok so I just installed my headers last week..got the rest of the exhaust componets on, everything back together (except I left my rear 02 sensors off...im going to get simulators) and now it really feels like my car is misfiring..especially at low rpm with high throttle. The car never did this before and ran great before I did this header swap. So once I had the headers on and drove it around and found out it felt like it was misfiring, I just assumed that either one of the spark plug wires got burnt through or I has accedently switched 2 of them up. So i went and bought boot protectors and new spark plug wires and installed them. All new wires with heat boots on the end of them. I am pretty sure that I have them all in the right spot because I did it one at a time and its kinda hard not to being as they are all diffrent lenths. So im about 90% sure its not the wires or the wiring order. I took my car to autozone to have them run the code check, and i assumed it was going to bring up a misfire on whatever cylinder was having the problem and of course my rear O2's. Well turns out, neither of those that I expected came up, and instead I was getting a P0100 - Mass Air Flow (MAF) Circuit Malfunction code. WTF? Would fixing this likely solve my misfiring problem? and maybe it isnt even misfiring being as it didnt throw a code for it...but it also didnt throw the O2 codes which kinda makes me think i just havent driven it around enough for it to code. What do you guys think?
I also have this code in my car ever since I installed the headers. At first my car ran fine, then it started missing like what you're saying. Although, since I awas already throwing the code and it ran fine I'm beginning to think that it's really just my opti or the coil. I tried a another maf sensor to and I still threw the 0100 code. Maybe we were idiots and burnt the wire. Maybe it's routed near the headers. I don't know. Can someone with knowledge shed some light in this direction??
On The Tree
Joined: Mar 2007
Posts: 198
Likes: 0
From: Tacoma, WA
ok so I just installed my headers last week..got the rest of the exhaust componets on, everything back together (except I left my rear 02 sensors off...im going to get simulators) and now it really feels like my car is misfiring..especially at low rpm with high throttle. The car never did this before and ran great before I did this header swap. So once I had the headers on and drove it around and found out it felt like it was misfiring, I just assumed that either one of the spark plug wires got burnt through or I has accedently switched 2 of them up. So i went and bought boot protectors and new spark plug wires and installed them. All new wires with heat boots on the end of them. I am pretty sure that I have them all in the right spot because I did it one at a time and its kinda hard not to being as they are all diffrent lenths. So im about 90% sure its not the wires or the wiring order. I took my car to autozone to have them run the code check, and i assumed it was going to bring up a misfire on whatever cylinder was having the problem and of course my rear O2's. Well turns out, neither of those that I expected came up, and instead I was getting a P0100 - Mass Air Flow (MAF) Circuit Malfunction code. WTF? Would fixing this likely solve my misfiring problem? and maybe it isnt even misfiring being as it didnt throw a code for it...but it also didnt throw the O2 codes which kinda makes me think i just havent driven it around enough for it to code. What do you guys think?
I also have this code in my car ever since I installed the headers. At first my car ran fine, then it started missing like what you're saying. Although, since I awas already throwing the code and it ran fine I'm beginning to think that it's really just my opti or the coil. I tried a another maf sensor to and I still threw the 0100 code. Maybe we were idiots and burnt the wire. Maybe it's routed near the headers. I don't know. Can someone with knowledge shed some light in this direction??
Also the pcm resets itself every now and then. So, sometimes the code for rear 02's will show up and sometimes it won't. Just depends.
Staging Lane
Joined: Jun 2007
Posts: 72
Likes: 0
From: Syracuse, NY
Take care of any vacuum/exhaust leaks clear the code and go through a drive cycle before you spend anymore money on stuff you don't need.
If the code comes back backprobe the maf connection and check to see your getting the right voltage etc...
If you tried using another MAF and it still didn't work check the wires for continuity.
I doubt a bad egr gasket would cause an unrelated code.
If you don't already have a nice multimeter go buy one.
Honestly if your throwing codes you should take care of them asap and not assume that because nothing seems to be going wrong it isn't. Using a tree method to deduce problem is the best way to go.
If the code comes back backprobe the maf connection and check to see your getting the right voltage etc...
If you tried using another MAF and it still didn't work check the wires for continuity.
I doubt a bad egr gasket would cause an unrelated code.
If you don't already have a nice multimeter go buy one.
Honestly if your throwing codes you should take care of them asap and not assume that because nothing seems to be going wrong it isn't. Using a tree method to deduce problem is the best way to go.
