I have a 2005 Scion xB 1.5L engine, standard trans... I was driving on the interstate and suddenly it started running rough. I pulled off the interstate and got about a mile before it finally just wouldn't run any longer. Tried to start it and it wouldn't start, so I bought an OBDII unit and the codes were as follows... P0101 - P0102 - P0113 - P0171 - P0133... I replaced the MAF and the IAC and then it started but would not run... (I also replaced the spark plugs with pre-gapped OEM iridium plugs just because it's been just over 5k since I changed them last) So anyways I cleared the codes and tried again and this time I got P0122 and P0511... I bought a new throttle position sensor and the same thing happens... it starts but won't run. I cleared the codes and tried again and it read 0 DTC... so now I'm at a loss.... maybe clogged injectors? But I would think it'd throw a code for that.... Any help or suggestions would be very much appreciated good sir... it has 195,000 miles by the way. And it ran great before this happened...
Hope you and your wife had a great Thanksgiving!!
O2 sensor was bad and there was a leak in an injector seal.
You didn't say what kind of scanner you bought but even a cheap one should be able to do this.
Hook it up, key on, go to Live data and find your TPS voltage and select that.
If your scanner can display it as a graph do that, if not just look at the voltage values.
The TPS voltage should read around 0 and as you slowly press the accelerator pedal the voltage should rise up to (near) 5 volts.
The reason you want to do it this way is because it's an easy way to see if all 3 of the wires (5 volt reference, Signal return ((ground)), and Sensor signal wire, going between the computer and the TPS are good without getting your hands dirty.
And if that is happening then you should probably go with an OEM TPS sensor because the computer doesn't like the signal voltage it's seeing from the TPS sensor.
I found it interesting that you suspect a fuel injector problem because if the computer doesn't like those TPS signal voltages, the computer won't increase the fuel injector pulse lengths (to add fuel) no matter how much you push down on the accelerator pedal.
Let us know what you find out.
Check the wiring to the throttle. Pray you got a wiring problem and not a failed computer. Because a bad ECM will trip that. Just make sure you got a good throttle position sensor. Not some cheap Chinese junk
