loss of power

[t4rFL]

i have an '01 4runner 4x4 auto and it is not my daily driver, but about 2 months ago i went on a 3000+ mile trip and as i was heading home (less than 800 mi. away) i started to have this problem where i would randomly lose engine power. basically nothing would happen when i hit the gas pedal. but it was on/off again, so i was able to keep driving. i was driving near mountainous/hilly terrain so i had kept the ECT button on most the way, which helped me since my rig was loaded with gear. after a while it was getting worse and was considering my options to get home. i also give the truck a few long rests. what i did notice was that it mostly happened after i release the gas pedal and then pressed on it again, that is when the symptoms would mostly occur. so at one point i decided to use cruise control (accel/decel) and turned off the ECT. i basically drove like that for the last couple hundred miles and in that time i never lost engine power.

now i do not daily my 4runner, but occasionally drive on the weekends and a few days to work and the problem never reoccurred.

i am thinking its possibly fuel related but am no expert, so what does everyone think it can be? the fuel filter was changed not too long ago, but no idea about the fuel pump.....if that is even the cause.

 

[t4rFL]

bump

 

[Boyds4Runner]

Did the car shudder with the loss of power or just seemed to not respond to the gas pedal?

I ask because I had an '04 SR5 and when I lost power it turned out to be a bad coil on the #4 Cylinder. However it would shake and shudder badly when I pressed the gas.

It occurred randomly and rarely throughout ownership of the car (starting around 36K then once every two years or so) but I could never get it to repeat itself. Shutting off and restarting the car would fix the problem and early on it never threw a code.

Finally, around 140K it failed enough to be there consistently and a local shop was able to diagnose the event. Replaced the coil for the #4 Cylinder and the issue never came back for the rest of the 42K miles before trading it in for my current 2015.

 

[SilverRidgeRunner1]

i have an '01 4runner 4x4 auto and it is not my daily driver, but about 2 months ago i went on a 3000+ mile trip and as i was heading home (less than 800 mi. away) i started to have this problem where i would randomly lose engine power. basically nothing would happen when i hit the gas pedal. but it was on/off again, so i was able to keep driving. i was driving near mountainous/hilly terrain so i had kept the ECT button on most the way, which helped me since my rig was loaded with gear. after a while it was getting worse and was considering my options to get home. i also give the truck a few long rests. what i did notice was that it mostly happened after i release the gas pedal and then pressed on it again, that is when the symptoms would mostly occur. so at one point i decided to use cruise control (accel/decel) and turned off the ECT. i basically drove like that for the last couple hundred miles and in that time i never lost engine power.

now i do not daily my 4runner, but occasionally drive on the weekends and a few days to work and the problem never reoccurred.

i am thinking its possibly fuel related but am no expert, so what does everyone think it can be? the fuel filter was changed not too long ago, but no idea about the fuel pump.....if that is even the cause.

When I encounter issues like this sometimes I throttle the engine to see if I can cause a trouble code a few things I would do to rule out fuel would be check your Fuel pressure and determine if its with in spec... Another option would be to take that same trip again with a Fuel pressure gauge attach and watch for pressure drops or at least replicate the issue enough to narrow it down .

 

[t4rFL]

Did the car shudder with the loss of power or just seemed to not respond to the gas pedal?

I ask because I had an '04 SR5 and when I lost power it turned out to be a bad coil on the #4 Cylinder. However it would shake and shudder badly when I pressed the gas.

It occurred randomly and rarely throughout ownership of the car (starting around 36K then once every two years or so) but I could never get it to repeat itself. Shutting off and restarting the car would fix the problem and early on it never threw a code.

Finally, around 140K it failed enough to be there consistently and a local shop was able to diagnose the event. Replaced the coil for the #4 Cylinder and the issue never came back for the rest of the 42K miles before trading it in for my current 2015.

never shuddered, just didn't respond

 

[tomatuvm]

Have you done all of the basic maintenance things like plugs, wires, MAF and throttle body cleaning, air filter etc? I had power loss and hesitation when I first got mine. Changed the plugs and it all went away.