engine hesitation

Hope you guys can help me figure this one out. fresh rebuilt engine with 1200 miles on it when i am in the expressway when i reach 60 mph right between 60 and 80 i can fell a slight engine studder when i accelerate.

 

Took to the dealer for the 1000 miles oil change. mention that issue to them. the tech took the car for a ride he also ran a diagnostic. he sad there was nothing wrong with it. yet the problem is still there.

 

Only thing i can thing of is i use 87 gas rather than the 91. i just found that out by chance today going through the owner manual.

 

 

any help will be appreciated

Yeah, start with again.

87 octane, I hope its a 2.5i.

which car?

 

what year?

 

what model?

its a 2005 legacy gt 2.5 turbo. engine was rebuilt due to the blown turbo that sent metal parts in the engine.

 

i been putting 87 since the sticker on the side of the gas cap door, clearly states 87 or higher. if what i did is big issue what can i do to rectify it.

 

 

thanks for all the help

87 is the MINIMAL ! If you read the manual, you'll see 91 is highly recommanded.

 

Plus, most of time, you put 91, you may have 90. So guess what happen to 87 ?

yeah dude its worth it to use the premium gas its only a couple bucks ($2-$4) more per fill and will run much better.

wow, do not put 87 in your car. It hates you. Do at least 91.

 

Not sure if that is what would cause your stutter...

k got it cool do i need to run a fuel injector cleaner

put a can of seafoam with the full tank of premium.

 

that should do it for you.

 

may be a good time to replace plugs or at least look at them.

roflcopter....87 in a GT??

I'm pretty sure it's safe to say 91 or better is basically required.

Seafoam in an engine that's only 1,200 miles old? Waste of money, unless it's still using the same injectors, which is possible.

 

And running lower octane fuel can cause detonation, pinging, and knocking.

the injectors are not specified as replaced.

Again, it's very possible the injectors are factory, as most replacement engines are sold as longblocks that require the installer to swap all the manifolds/electronics/accesories.

 

I guess clogged injectors are a real possibility afterall.

 

The only thing is that if it were the injectors, wouldn't he have had similar problems before the engine swap? I mean, it's not uncommon for strange things to happen, but don't you think it would be kinda unlikely that the injectors would be fine in one engine, than after swapping the manifold/injectors to a rebuilt longblock they decide it's time to die?

 

Either way, it's a possible solution that's under $10... Might as well try it. Just don't put it anywhere else other than the gas tank, that stuff can be a blessing or a curse depending on how you use it.

Ny gas lid says premium only.

thank you guys for all the help i really appreciate that i did dump a pint of seafoam and will replacing the sparkplugs this weekend.