GUys need help, completely LOST at this point...

[nafeasonto]

Okay my friend has a 96 Toyota 4Runner, 3.4L

This is the issue:

On acceleration from IDLE, the car sputters for POWER and eventually "catches" and gets powers, but the more the thorttle body is open or more air, the more it struggles, BUT a cruising the car is fine. Say he is at 50MPH but he wants to go for 60, then the car struggles to get to it, but once it gets there and he smoothes out the thorttle, the car is fine.

The car also Idles like a master.

Now on this 4runner this has been done:

1. Ignition coils, (all three of them)
2. Wires, all three of them.
3. New spark plugs
4. New INtake manifold gasket (due to heavy leaks)
5. New fuel filter (hadn't been replaced in 16 years.)
6. 4 of the 6 injectors have been replaced due to them failing, I replaced the O Ring seals on the two others as they were leaking fuel, they are fixed.
7. PCV Valve replace (again 16 years old)

I sprayed with carb cleaner, did a smoke test, I CAN'T find any damn vacuum leaks ANYWHERE.

WITHOUT fail, every single time from IDLE the car sputters for power, then the power catches. NO CEL, NONE. I cna't stand it.

Does anyone have ANY suggestions on what in the hell it could be.

 

[Brian757]

Okay my friend has a 96 Toyota 4Runner, 3.4L

This is the issue:

On acceleration from IDLE, the car sputters for POWER and eventually "catches" and gets powers, but the more the thorttle body is open or more air, the more it struggles, BUT a cruising the car is fine. Say he is at 50MPH but he wants to go for 60, then the car struggles to get to it, but once it gets there and he smoothes out the thorttle, the car is fine.

The car also Idles like a master.

Now on this 4runner this has been done:

1. Ignition coils, (all three of them)
2. Wires, all three of them.
3. New spark plugs
4. New INtake manifold gasket (due to heavy leaks)
5. New fuel filter (hadn't been replaced in 16 years.)
6. 4 of the 6 injectors have been replaced due to them failing, I replaced the O Ring seals on the two others as they were leaking fuel, they are fixed.
7. PCV Valve replace (again 16 years old)

I sprayed with carb cleaner, did a smoke test, I CAN'T find any damn vacuum leaks ANYWHERE.

WITHOUT fail, every single time from IDLE the car sputters for power, then the power catches. NO CEL, NONE. I cna't stand it.

Does anyone have ANY suggestions on what in the hell it could be.

We might be undergoing the same thing. I've been having a rough running for a week now, and have finally put it in the shop. I have replaced everything that you listed, with the exception of my intake manifold gasket. I will let you know what the shop says. It might shed some light for you.

 

[nafeasonto]

Yeah I cleaned the plenums, and cleaned the huge amount of carbon buildup, cleaned up the base of the lower intake, before putting the new gasket on. the car runs better, but the problem is still there.

 

[Doc2012]

Very Possibly the Throttle Position Sensor.

 

[MStudt]

Very Possibly the Throttle Position Sensor.

x2

These are known to be issues.

 

[nafeasonto]

The problem has been going on for months, shouldn't it throw off a code by now?

 

[nafeasonto]

Any other suggestions or is the tps the main though?

 

[Mtechnick]

Sounds very similar to my issues. Does he have any engine lights ? I'm going to buy a tps it can't hurt I guess .. I'll let you know tomorrow

 

[revenantdead]

clean the maf?

 

[nafeasonto]

MAF has been clean, and tested with a VOLT meter it tested good.

 

[nafeasonto]

Sounds very similar to my issues. Does he have any engine lights ? I'm going to buy a tps it can't hurt I guess .. I'll let you know tomorrow

Yes let me know, I am curious on the WTF is going on with this car.

 

[Singtoe]

Chk your grounds for conductivity.

 

[nafeasonto]

Chk your grounds for conductivity.

Which grounds specifically, there are A LOT on that car.

 

[bpowa]

Check cam position sensor.

Are you sure your wires are routed correctly?

Does it throw a engine code?

 

[nafeasonto]

Check cam position sensor.

Are you sure your wires are routed correctly?

Does it throw a engine code?

Wires are routed correctly, and there is NO CEL. That is what is driving me crazy.

WIre are routed:

1-4
3-6
5-2

 

[Singtoe]

Which grounds specifically, there are A LOT on that car.

There two on the intake manifold, there are 2 on fire wall and there are some at the battery.

 

[Mtechnick]

Yes let me know, I am curious on the WTF is going on with this car.

FYI the tps did not fix my issue. It was fixed changing the upstream o2 sensor 150 miles so far and no codes or issues.

 

[nafeasonto]

FYI the tps did not fix my issue. It was fixed changing the upstream o2 sensor 150 miles so far and no codes or issues.

were you gettiong a code before, because I am getting no codes.

 

[nafeasonto]

he is going to bring it to his mechanic, I don't have the tools to test the CAT or the 02 sensors.

 

[Brique]

Could it be related to the fuel pump, possibly? Maybe check the ground for the pump. I heard of a completely different truck having a similar problem and it turned out the ground for the fuel pump had corroded. Our truck may be a completely different design, though. I dunno.