Engine feeling sluggish

My friends 3.4l 4x4 trd is feeling sluggish. No codes popping up, but shifting ok but motor feeling underpowered. This is the truck that got water but have replaced the starter, alternator, MAF, GF, and 4WD computer. Any ideas what it might be. thanks in advance for suggestions

 

verdict: Timing Belt, replacing water pump since already in the way

 

good idea.....may wanna look at replacing seals in there too since you'll be in there, and depending on when the other belts were last changed, may be a good idea to change them too.

 

So...the timing belt was the fix for it running sluggish?

 

No, it won't. The ONLY effect a T belt will have is 1. engine will not start/run (belt broken), or 2. running like complete crap (belt jumped a tooth, but not likely to happen). I would check standard items; plugs, fuel filter, air filter first.

 

It was the timming belt it had skipped a toothed got that rollers & waterpump replaced works like a champ, they also checked the fuel press regulator n said it might be next the pressure is a lil low

 

wow, I've been a Toyota mechanic for 7 years and have yet to see a 5VZ FE run "sluggish" that jumped a tooth. Learn something new everyday.

 

Thanks mcorbin. My truck feels like something is holding it back at full throttle. It seems fine any other time. I bought some Denso plugs today and will also get a fuel filter. I may also run some Seafoam through it.