2003 Suburban with 143000 miles. Has ran perfect until a few days ago. Now while trying to accelerate it boggs down and misses. It starts and idles perfectly. The following codes are being read P0101 maf or vaf P0120 pedal position circuit P0220pedal position misfire b P0300 random multiple misfire P1514
P2135 Aand B pedal

Just curious if anyone else has experienced this problem and if so how it was fixed. Maybe wishful thinking, but I feel like it is probably a simple fix. I have cured most of the other Suburban problems with little expense. The front end popping while turning, 5 minutes and wd-40. Instrument gauge problems with new Ebay step motors, thumping the plastic gas tank when it wont start, cleaning window control panel and switches to fix locks and windows. Thanks for any help you might be able to provide, Thanks

 

Check the fuel pressure.