I already know what the codes refer to, pre-cat O2 sensor bank 1 (P0130), and bank 1 lean (P0171). I'm just curious to know if there's anything else it could be. I doubt it's something the cylinder itself, meaning injector, slipped liner, sticky valves, or the other bad things because it would have caused a dreaded misfire code.
The problem came on quite suddenly. I put 1800 miles on the '03 no problems, no dash lights, ran great. Then I accidentally filled it with 87 octane regular unleaded. Within 40 miles, P0130 came up. There was an old code stored there too, but that one hasn't come back. I drove it for 250 miles, occassionally being able to drive 20-30 miles before getting the code. It almost seemed as if--if I was going to get the code at all, it was going to be when the engine was cold or not quite warmed up yet (it's been anywhere from -20F to 25F here lately).
After driving 250 miles getting rid of the 87 octane, I filled up with 91 octane (no ethanol either) from a good gas station hoping the code would stay gone. Well, within 20 miles of that, I parked somewhere for about 2 hours and the engine got cold enough to be "cold." When I started it up, it instantly idled rough, the SES light came on again, and after 10 miles of driving, I got both the P0130 and P0171 codes. I cleared the codes, they came right back, I drove home another 20 miles and parked it a few days ago.
The engine seems to run smoothly above idle, but not at idle. I already checked the MAF--it was perfectly clean. I cleaned it with CRC MAF cleaner anyway. There don't seem to be any exhaust leaks, and certainly not enough to "tick." This weekend I plan to swap the 02 sensors from driver side to passenger side to see if the problem moves. The only coincidence I can think of is that the heater plate gasket and one of it's hoses decided to leak badly about 2 weeks ago, dripped all over on top the driver valve cover, down the engine, and drip right onto the 02 sensor in question. I'm going to check that electrical connector tomorrow--maybe it got corroded from coolant?
Anyway, I'm just looking for other things I can check while I'm doing this. I've only had this darn truck for 3 weeks and I can only drive it for about 2 days before something else fails. Nothing major yet, but still incredibly annoying! I have a ScanGauge2, but I haven't learned how to use it yet. Perhaps it can help. I have a regular OBD2 code reader as well, but it does not give me live info.
The problem came on quite suddenly. I put 1800 miles on the '03 no problems, no dash lights, ran great. Then I accidentally filled it with 87 octane regular unleaded. Within 40 miles, P0130 came up. There was an old code stored there too, but that one hasn't come back. I drove it for 250 miles, occassionally being able to drive 20-30 miles before getting the code. It almost seemed as if--if I was going to get the code at all, it was going to be when the engine was cold or not quite warmed up yet (it's been anywhere from -20F to 25F here lately).
After driving 250 miles getting rid of the 87 octane, I filled up with 91 octane (no ethanol either) from a good gas station hoping the code would stay gone. Well, within 20 miles of that, I parked somewhere for about 2 hours and the engine got cold enough to be "cold." When I started it up, it instantly idled rough, the SES light came on again, and after 10 miles of driving, I got both the P0130 and P0171 codes. I cleared the codes, they came right back, I drove home another 20 miles and parked it a few days ago.
The engine seems to run smoothly above idle, but not at idle. I already checked the MAF--it was perfectly clean. I cleaned it with CRC MAF cleaner anyway. There don't seem to be any exhaust leaks, and certainly not enough to "tick." This weekend I plan to swap the 02 sensors from driver side to passenger side to see if the problem moves. The only coincidence I can think of is that the heater plate gasket and one of it's hoses decided to leak badly about 2 weeks ago, dripped all over on top the driver valve cover, down the engine, and drip right onto the 02 sensor in question. I'm going to check that electrical connector tomorrow--maybe it got corroded from coolant?
Anyway, I'm just looking for other things I can check while I'm doing this. I've only had this darn truck for 3 weeks and I can only drive it for about 2 days before something else fails. Nothing major yet, but still incredibly annoying! I have a ScanGauge2, but I haven't learned how to use it yet. Perhaps it can help. I have a regular OBD2 code reader as well, but it does not give me live info.
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