Sluggy uphill sometimes

Hi all,
This is my first Toyota... ever. I just got this Taco (2009 4.0 4x4 TRD Off Road)

I am having an issue with loss of power suddenly going uphill (about 50% of the time). I have checked the Toyota website by VIN# and LIC# for any of the recalls and they seem to have been addressed. I tried to purchase a new TPS but I guess they don't have one? Not sure where to go from here.

I also heard that from the previous owner he was having issues after changing the spark plugs. Is there a specific brand I need to go with and what is the gap set at?

Thanks

 

I think it may be your 6” lift and 20” M/T tires in your avatar specs. Your trying to drag an anchor up hill.

 

these trucks dont really have that much power to start with, add a lift and heavy tires and yeah it might struggle going up hills.

push the pedal down a little farther next time.

 

Is the MIL on?

Can you link the loss of power to any particular circumstance/trigger? eg. does that "steepness" of the hill have any effect; the weather; your speed; or, your weight?

I agree that your lift in tires are going to make the truck feel a bit sluggish, but that doesn't account for a sudden loss of power.

Beg, borrow, or 'acquire' a good scan tool, and check for trouble codes; there can be lots of stored codes that will be good clues, but which won't trigger the MIL.

 

I'm definitely not keen on the wheels... not my style... I have taken that into consideration.
I also heard that from the previous owner he was having issues after changing the spark plugs. Is there a specific brand I need to go with and what is the gap set at?

 

So I have went up the same hill 7-10 different times... fairly steep grade... somedays it cruises up at 65 w/ no issues... other days I have to stomp down on the pedal to get it to move.

 

Test coils
When were plugs changed last! And if ya did, did you gap them right

 

Changed aboout 2 months ago - The old owner changed them before I took ownership. I am thinking I am just going to re-gap and try that... Whatever the gap is.

 

New spark plugs denso K20HR-U11 gapped to .041 $26.04 Amazon (old spark plugs passenger side denso k20hr-u11, drivers side ngk LFR6C).

That is what was put in my notes for changing my plugs. Knowing me .041 is in the middle of the spec range for gapping. I have owned since new and the Tacomas came with different brand plugs on each side of the motor (not sure why)

 

Okay, that's weird... Mabye that is the issue and they used the same plugs for both banks? i'll know more this weeekend.

I wanted to get some input from everyone before i went sideways with buying random parts.

Thanks

 

Not sure what "MIL" is...

I have a code reader and will tend to that this weekend. Just trolling around for where to look first. Usually when it starts is shortly after i begin a grade; It will just start slowing down like I am pulling a heavy load, it will drop a gear and continue slowing, until I step on the pedal... It drops another gear and accelerates, but still like I am pulling a heavy load.

When it is running fine, even with the lift and 20's, i can zip right up the hill with no issues, 60-70-80 mph

 

Malfunction Indicator Light = Check Engine Light

 

It's just that Toyota puts in two different brands of plugs when they build the truck; there are a couple of message threads you can find that discuss the possible reasons why they choose to do this. But you don't need to continue the practice, generally the recommendation is to put in the Denso K20HR-U11 all around. I just did this in mine and they're working great.

 

total miles on engine

issues are Not always recall dependent

brand o sprkplugs installed correctly wouldnt lead to loss o power

whie they are out..........................keep in order per cylinder

do a compression test

 

Some people have driveability issues when running anything other than OE Denso or NGK Copper plugs so stick with them.
As to why the 4.0l trucks come with 3 NGK and 3 Denso nobody know for sure, there's many theories but I haven't seen any hard evidence as to why.

 

different sides of the production line

right hand dont know what the left is doin

side by side ...........little difference

 

To be clear, the new ones I put in are all the same Denso plugs. No problems with all the same.

 

If the problem started after the PO installed plugs then I'd be checking his work. Pull the plugs out and see if they're the correct ones Dm mentioned above. Look the coils over closely for cracks or carbon tracking. Are all the vacuum lines plugged in?

Have you scanned it for codes yet? Does the check engine light come on with key on?

Next step would be looking at short/long fuel trims when the problem happens.

 

Update:
Pulled the plugs (NGK Laser Iridium); they were gapped incorrectly .033-.039 and just barely snugged to the head.; I gapped to spec .044 and torqued to 15 ft. lbs. it runs ALOT better. but now that I'm paying more attention, it seems like it's shifting late/slow. I'll check the speed sensors and update. Even with the big ghetto wheels it now pulls the hills at a decent rate.

The previous owner was hard on his vehicles all around, so I'm assuming he never did any preventive maintenance. I also just ordered the shim kit to chase away the vibrations at takeoff.

I'll continue to update.

Thanks for all the help