Code chasing

Barberdisco1

Member
Jan 18, 2017
16
0
Idaho
So I've been chasing codes and now they are all gone, I've replaced crank sensor,cam sensor,fuel temp sensor, fuel pump, all 4 o2 sensors,water sensor, and I'm still getting a hesitation and misfire at about 35 MPH. I'm at a loss any suggestions would be nice I'm looking into replacing vss.
 

discostew

Well-known member
Sep 14, 2010
7,706
1,015
Northern Illinois
4Runner is probably on to something here. But don't just go buy a sensor. If you don't have a scanner measure the voltage at the three wires of your TPS. I'm betting that your 5 volt reference voltage for the TPS is being pulled low by your fuel tank pressure sensor. If you just want to cut right to the chase go back to the fuel pump and disconnect the fuel tank pressure sensor and see how it runs.

Do that before you do anything else. I really doubt your TPS failed, it's probably the fuel tank pressure sensor.
 

Barberdisco1

Member
Jan 18, 2017
16
0
Idaho
So I went out tonight drove 30 miles it jumped sputter d an misfires whole way no check engine light, ran 15 miles with scanner in ran 15 miles without no codes#
 

discostew

Well-known member
Sep 14, 2010
7,706
1,015
Northern Illinois
4Runner is probably on to something here. But don't just go buy a sensor. If you don't have a scanner measure the voltage at the three wires of your TPS. I'm betting that your 5 volt reference voltage for the TPS is being pulled low by your fuel tank pressure sensor. If you just want to cut right to the chase go back to the fuel pump and disconnect the fuel tank pressure sensor and see how it runs.

Do that before you do anything else. I really doubt your TPS failed, it's probably the fuel tank pressure sensor.

What is the TPS voltage on the scanner? It's possible the problem I'm talking about won't store a code.
 

Barberdisco1

Member
Jan 18, 2017
16
0
Idaho
It's an Ael system if that helps.
And fuel tank pressure sensor must be one of the plug ins on top of fuel tank. I'll report back toda
 

Barberdisco1

Member
Jan 18, 2017
16
0
Idaho
So I have unplugged brownish red plug didn't change vehicle issues ,unplugged little black hose nothing, throttle sensor maybe? I'm going mad lol
 

Barberdisco1

Member
Jan 18, 2017
16
0
Idaho
So thank you everyone for the ideas ,I found the issue it was a broken wire near fuel tank I'm guessing it was making some sort of connection then cutting out ,it to me longer to check it because of work and crappy weather, so ty again