I got my truck to throw some codes. As many of you know I have been having an issue where when I stomp my truck to the floor it sputters and hesitates. Some days its worse then others. It only happens under a load, and it generally doesn't last to long, however today it did it a whole bunch and lasted for a good bit any time I got on it hard. My engine light begin to flash, and there was a smell of exhaust. I went to Autozone quickly as possible. The guy read the code, and this time no lean codes, just a "P0430" which the code reader said was O2 Sensor Bank 2. It also had a pending code, which was "multiple cylinder misfire detected". So my question is can an O2 sensor cause this? Could my CAT on that side be bad?

If that is all it is, is a bad cat or O2 sensor then I will be very happy... Like I said I can sit in my driveway in park all day long, and rev the **** outta my truck. It will never misfire or hesitate at all. Soon is I put it in gear and am going down the road and punch it sometimes it pop and sputter.

Another cool thing is some how their code reader was able to read my ABS light, and I found out that this whole time I have had a bad ABS Speed Sensor in the rear end. That is a plus as well.

If anyone can please help me out with this It'd be much appreciated. I just need to find out what it is I need to replace. So far I have had my plugs replaced. My mechanic that I talk to told me it was an intake gasket leak, but I believe he was wrong.

 

I know someone here has an idea? Surely?

 

two things first for your rear abs if you have dual exhaust look at you wires on the passenger side above the axle because my light came on a few weeks ago and i had the code read and when i went to see if it was easy to change i seen where the wire cover had been smashed and when i pulled the wire out i seen it was cut from slaming my exhaust somehow???
second i had the same thing happen to mine with the popping and missing under load but never in park when reving but mine was a broken plug.

 

I gotta figure the O2 sensor would be responsible for the lean code. If the PCM is getting a false signal that the mixture is lean it is going to try to adapt. That would result in a ich mixture that I think would cause your symptoms. You need a scan tool that can monitor fuel trims.

 

I don't think its a plug. Its multiple cylinder misfire, and it was a pending code, and the O2 sensor code was thrown first. If anything it could be the cat. It defiantly is one side of the engine, and not the other. Everything has pertained to one side. The lean code showed up once, and hasn't came back yet. Today I got it on a country back road and constantly floored it, and let off. It happened pretty quickly, the truck begin to pop and sputter, and at one point I had it doing it so bad that I barely was touching the gas and it was doing it. My engine light was flashing, and it just started acting okay again, I mean it was still doing it, but not as severe, but by then I quit trying to make it do it, and went to autozone and had them read the codes.

I just don't wanna spend 60 bucks on an o2 sensor and it be a bad cat, or spend 150-200 on a CAT and it be a simple fix like the O2 Sensor.

On a side note, where exactly is the other O2 Sensor. There was one after the CAT, didn't see another one. There should be four right? Both cats have a O2 Sensor after them, but there should be two more.

I do have dual pipes.. Gonna check out that ABS sensor tomorrow..

 

yes, your sensors should be on both sides of the cats but the cats are so close to the manifolds maybe they are hard to see.

 

Yeah I can see my cats fine. I can see both O2 Sensors. in front of both cats. There should be another O2 Sensor else where though if I am not mistaken, are those up towards the manifolds?

 

I have just went through the exact same problems, exact same codes. I changed my plugs about 6 months ago and that solved the missing code, but the P0430 code remained. I was driving with the engine light on for the last 6 months, and finally decided it must be the cat. Just got magnaflow cats installed yesterday and within a couple min of starting the truck the light went off. The old cat had about a 1.5 inch hole straight through the honeycomb. I believe when the truck was missing it was dumping extra fuel in the exhaust on that side and melted out the internals.

 

I am almost 100% certain it ain't my plugs. My plugs may be the culprit but I doubt it considering the stealership supposedly replaced them. The code I did get out of the truck before the O2 Sensor, was a system to lean on bank 2 code. Which there again, bank 2. The injectors aren't bad, and the fuel rail seems to be fine according to a local mechanic everything on the top end of the motor is great, besides the plugs which he couldn't check because he was afraid he'd break them obviously.

Would bad plugs cause a lean code?

 

What was the other misfire code?

 

I didn't get it, because its pending. I'll have it read again, and get it. The code was just "multiple misfire detected" and it was pending. In the past I have gotten codes for cylinder 7 and 8 misfire, and I also have gotten a lean code on bank 2. I never got the exact numbers for those codes back then, but someone here told me to start posting the numbers. I'll go and get them read right quick.

 

To diagnose this yourself you're really going to need a code reader. I have this one from harbor freight and it really does a pretty good job for the cost. You will be able to read pending codes and graphically live stream data such the O2 sensors and fuel trims.

CAN OBD II Code Reader/ EOBD Scanner

 

Heres the codes I got... in a list..

P0174
P0430
P2106
P0307

 

P0174 System too lean bank 2
P0430 Catalyst system efficiency below threshold bank 2
P2106 Throttle actuator control system-forced limited power.
P0307 Cylinder no 7 misfire detected

Did you get a code reader or is this what you got from the Autostoned guys? I think you've got a bad cat and maybe something else is bad that led to that. Could be an 02 sensor or the sparks were bad for a while maybe an injector stuck..

If you have a code reader you should monitor the fuel trims and 02 sensors and do some loaded and unloaded throttle excursions.

 

It only does this **** when its under a load. Sometimes worse then others. I defiantly wanna figure out what it is. I hate to drive the truck around like this, I mean its completely fine if I don't give it to much throttle, and sometimes even then it works ok. I didn't go to autozone. I had a mechanic read these codes. In fact I got to hold the code reader and write them down. He wanted to charge me to do anything else. I don't have the cash just yet for a code reader. I am saving up to just buy a Edge Tuner... I work construction and we've been pretty dead at the moment so I have to conserve money, and if I buy a reader then I won't have the cash to fix the problem anyway, plus Christmas is coming up, and I have little ones to buy for hehe.

It doesn't feel like the truck ever misfired per-say, not bad anyway, and I believe the first time I had the codes read I had a cylinder no. 8 misfiring with number 7, but also I was getting a lean code then to. I haven't owned this truck very long, and since I got it, its done the same thing. Even after the plugs were replaced. It doesn't misfire at idle, or it don't idle rough, it runs great under load until you give it to much gas, then it starts that sputtering, and popping ****, which sometimes will be excessive and carry on until I let off the gas, and floor it again. Sometimes it will happen for a few seconds, and go ahead and go.

I can afford to replace the O2 Sensor, and the CAT, but I wanna make sure those two are my under lining cause, before I do that.