03 4Runner will not accelerate under load

Hi there!

I have an interesting (annoying) problem with my beloved 4Runner.

I have an '03 Limited with about 230,000 miles with no modifications. In the last few months, I have been losing the ability to accelerate when at higher speed or uphill. The engine is revving high but the power isn't getting to the wheels. The kicker is that there are engine codes.

I had it to a Toyota diagnostician, a friend, who couldn't seem to figure it out but he said that the driver side cat was running at like 600 degrees and the passenger cat was much lower. I swapped out the driver side cat and now the passenger side cat is hotter than the driver side and it still had the same problem. BTW, the cats on there were replaced in 2021 so they are relatively new.

I replaced the MAF also but that had no impact.

The car is drivable but a bit dangerous as I cannot climb steep hills or merge or pass!

I am so deeply bummed out because I love this truck and it has been so good to me and I feel safe driving it.

Any help would be appreciated!

 

Please post what codes you have.

 

Heya. Thanks for looking! That's the problem--no codes. No codes on the diagnostic tool while driving, either

 

High exhaust temperature could mean it's running lean. Maybe have the fuel system looked at.

 

Thank you! I will run it by the mechanic but he's very puzzled because there is no smell, no stalling and no trouble starting to indicate running lean but I will def mention it to him.

Thanks again!

 

I asked for codes because you said in your original post......"The kicker is that there are engine codes."....I'm guessing now that you meant to type...The kicker is that there are no engine codes.

 

Get your fuel pressure checked. I'd put my money on a weak fuel pump.

 

MY BAD! NOOOO CODES! Thank you AuSeeker!