Stumped Toyota Service Department with this issue- can you help?

[krs1040]

When I try to accelerate quickly or when I am going up a hill my 4 runner pulses. It is a temporary loss of power under load that causes it to jerk. I initially thought the transmission was slipping but now think it could be an engine issue. I took it to Toyota and they found a leaking axel seal and assumed the fluid was building on the brakes and causing them to catch. Fixed the brakes and still have the issue and Toyota did not know what was wrong granted it was not as bad then as it is now. Have added transmission fluid to stop slipping and it did not help. It does not happen all the time and seems to happen when the engine is under load. Any thoughts? 177K miles on my '96 V6.

 

[KellyJ]

Sounds like there could be a problem somewhere withing the fuel delivery system - clogged injectors possibly? Carbon buildup?

 

[bgmac]

spark plugs/coils will cause your vehicle to do the same thing

 

[jmrwd3]

WOW!! This is exactly what was happening to me! I replaced all my spark plugs and wires, but it turned out to be a bad ignition coil. They are expensive, so i had the coils checked, not sure how the shop checked them. But they found one to be bad so i replaced them all.

 

[krs1040]

Did you have the dealership do it? What did it cost you to have them all done?

 

[shootmymime]

also try changing the fuel filter

 

[techno]

Did you have the dealership do it? What did it cost you to have them all done?

The coils are very easy to replace. All three can be checked and replaced in less than 30 mins. No special tools needed other than a multimeter. Five of the plugs (on a V6) are easy to change, the sixth one (d/s rear) is a pita but doable with skinned knuckles or a 5 year olds hand.

Also, I'm extremely surprised that the Toyota dealer concluded that a LUBRICATING fluid would cause brakes to start catching when in fact the absolute opposite will happen. I suggest avoiding that dealership in future.

 

[scotts97T4Rltd]

mine does the same thing, unless you hit wide open throttle. It is probably 1 of 2 things, either the oxygen sensor, or the TPS sensor. With 178k on the clock, it is time for a new oxygen sensor, so thats what i will be replacing soon.

 

[eddie4christ]

Thats weird, my truck started doing that today, I have 106,000, sparkplugs are newer, and mine seems that its at stops and beginning acceleration that it seems to vibrate, as if my alignment is off... But going full speed no problem... The Check Engine light came on for a bit and then disappeared, it came on a little later flashing but turned off once i pulled into Checker to have a reading taken... Its weird, it just snowed here in Colorado so it might be because it was super cold all day... I'll keep you posted...


P.S. what are you referring to with the "TPS" sensor?!?

 

[ChildrenOfBodom]

Thats weird, my truck started doing that today, I have 106,000, sparkplugs are newer, and mine seems that its at stops and beginning acceleration that it seems to vibrate, as if my alignment is off... But going full speed no problem... The Check Engine light came on for a bit and then disappeared, it came on a little later flashing but turned off once i pulled into Checker to have a reading taken... Its weird, it just snowed here in Colorado so it might be because it was super cold all day... I'll keep you posted...


P.S. what are you referring to with the "TPS" sensor?!?

Throttle Positioning Sensor

I actually replaced mine too when I got a check engine light a few months back.

 

[eddie4christ]

Thanks for the clarification... So did you replace it yourself or have the dealer do it?!? If I could do it on my own then I'd rather do that... The funny thing is this morning the pulsating and light came on, but after a couple miles it went off and the pulsating stopped!

 

[blk runner00]

i would check the mass air flow i had trouble with mine. starting off from a stop sign it would shake and sputter under any load. i had a buddy at a toyota dealer test the MAF and it was bad. put a new one in and was running like new

 

[eddie4christ]

FIXED! YEAH!!!! So like I said, all that sputtering and lack of power all came to an end today. I went to checker and bought a new air filter and some throttle cleaner and MAF sensor cleaner... So after cleaning all that, I went down underneath to the frame and switched out my fuel filter. Whoever hasnt checked on their fuel filter lately, I STRONGLY recommend you swap it, the fuel coming out of mine was as thick as mud! Obviously the previous owner didnt keep up with the maintenance...Anyways guys thanks for the help!!!!

 

[shawnstcyr]

glad you got it fixed. mine did that right before the harmonic balancer broke

 

[eddie4christ]

I started a new post on this whole TPS stuff... But just another update, the stuttering is back and the trembling at high speed is back... I replaced the fuel filter, the MAF is clean, new air filter, and new NGK plugs... So Im hoping the TPS is just dirty, but if you guys have pics Id appreciate you posting...

Also note that the engine is receiving plenty of air, the stuttering and trembling only comes with application of the gas pedal, so anymore advice would help! THANKS

 

[triblk6spd]

Coils? Wires? O2 sensor? The fuel filter may be reclogged as well if the last one was that bad.

 

[bgmac]

spark plugs/coils will cause your vehicle to do the same thing

You need to replace those coils. I had the exact same problem you are describing a few years back and it was the coils! Do you have a friend with a 4runner? try swapping them out first to see before you go out and buy them.

 

[eddie4christ]

I just checked the TPS and its clean and clear, so the coils huh! Bummer Im the only stinkin 4Runner in the neighborhood! Do you know what the ballpark figures are for buying new ones, the installation shouldnt be a problem