Error Code P0172 (now P0174) Not Fixed
I have a 2006 Tundra double cab with 331,000 miles. Yep, that's quite a bit of seat time. The truck is 100% original, with only the lower ball joints replaced. Anyway, on to the P0172 problem.
A few days ago, when starting the truck in the AM, it stumbled just a bit. That was odd as it never did that before. (I am extremely aware of the performance of this truck, as I am trying to baby it to 500,000 miles).
I also had noticed over the last month, the engine temp was about 15% higher than normal. Nothing huge, just an indication of something. I figured with the high mileage, the radiator might be suspect. However, it is clean and no signs of any corrosion. I just wrote it off as a sign of age.
The following day. in the afternoon, I started the truck, and it threw up the Check Engine Light. Rats. 300K miles and this happens.
I took it to my local smog station and they read the code as P0172 (he said engine running lean, though some code translations say engine running rich). Whatever, time to figure it out.
Using these forums, I naturally found many potential solutions. Throttle body, MAS, Vacuum leak etc.
I cleaned the throttle body, reset the code (disconnect the battery), and drove it. Within 10 miles, it threw the code again. Rats! BTW, cleaning the throttle body did make a noticeable improvement in throttle response but the idle was low at approx 500.
Dumbfounded at this point, I kept reading about MAS being dirty. Worth a shot. Two screws, removed the MAS, hit it with MAS cleaner, reinstalled. 5 minutes max.
Took it out for a test drive. I noticed immediately the engine temp was back down to its normal range, (not the 15% increase in temp I mentioned earlier) Further, the idle went from 500 to 750, where it should be. Drove it 20 miles with no codes. Great throttle response,
it idles smoother . I firmly believe the issue is solved. If not I will report back.
Thank you to all of you that contributed knowingly or not, for your help.
I have a 2006 Tundra double cab with 331,000 miles. Yep, that's quite a bit of seat time. The truck is 100% original, with only the lower ball joints replaced. Anyway, on to the P0172 problem.
A few days ago, when starting the truck in the AM, it stumbled just a bit. That was odd as it never did that before. (I am extremely aware of the performance of this truck, as I am trying to baby it to 500,000 miles).
I also had noticed over the last month, the engine temp was about 15% higher than normal. Nothing huge, just an indication of something. I figured with the high mileage, the radiator might be suspect. However, it is clean and no signs of any corrosion. I just wrote it off as a sign of age.
The following day. in the afternoon, I started the truck, and it threw up the Check Engine Light. Rats. 300K miles and this happens.
I took it to my local smog station and they read the code as P0172 (he said engine running lean, though some code translations say engine running rich). Whatever, time to figure it out.
Using these forums, I naturally found many potential solutions. Throttle body, MAS, Vacuum leak etc.
I cleaned the throttle body, reset the code (disconnect the battery), and drove it. Within 10 miles, it threw the code again. Rats! BTW, cleaning the throttle body did make a noticeable improvement in throttle response but the idle was low at approx 500.
Dumbfounded at this point, I kept reading about MAS being dirty. Worth a shot. Two screws, removed the MAS, hit it with MAS cleaner, reinstalled. 5 minutes max.
Took it out for a test drive. I noticed immediately the engine temp was back down to its normal range, (not the 15% increase in temp I mentioned earlier) Further, the idle went from 500 to 750, where it should be. Drove it 20 miles with no codes. Great throttle response,
it idles smoother . I firmly believe the issue is solved. If not I will report back.
Thank you to all of you that contributed knowingly or not, for your help.