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engine swap..used engine..smog test..tank of premium gas..gas additive…

Customer Question
i did an engine swap...
i did an engine swap. the current used engine passed a leak down test and a smog test w/ good results. i put a tank of premium gas in it and a gas additive, which helped some, yet not long term. it is not over heating.

it is getting slightly less gas mileage than before the swap - went from 19 mpg to 17 or less on a mountain road - and has significantly less power when accelerating, especially up a steep incline, but also on a straight flat road.

before the engine swap, while going up the mountain i live on, it would accelerate easily to 50 mph. now, it takes twice as long to get to overdrive, and while its taking its time, it likes to be between 35 and 40 mph.

it feels like i have to apply more pressure to the gas pedal, in general, to get it to accelerate. when i apply that extra pressure, it feels somewhat unnatural, like it has to work hard to respond.

i can floor the gas going up a steep incline, and it doesn't make a difference. on a flat road, it does accelerate quicker, yet it feels delayed/strained. either way, it feels like a lot of pressure to the pedal - more than before the swap.

before the swap, it also liked to ease into accelerating, yet it went fast enough, soon enough, that i didn't feel the lack of power. now, it seems to lack significant power. in other words, it felt like it needed to be babied before, not driven hard, yet it would still increase speed soon enough that i could keep up with the flow of traffic and the speed limit. not so now, i am noticably slower, and have to let people pass me.

should i be concerned about the transmission or is there something else to investigate?

is this related to the engine swap or not?
Submitted: 8 years ago.Category: Subaru
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Answered in 20 hours by:
6/27/2010
Subaru Mechanic: wrxteck, Subaru Technician replied 8 years ago
wrxteck
wrxteck, Subaru Technician
Category: Subaru
Satisfied Customers: 39
Experience: subaru factory certified technician
Verified
Hello...sounds like alot going on....let me ask you this....was the motor you put in taken apart and rebuilt and then put in your car??? If so then i suspect the timing belt maybe off a tooth or two??? Need more info on exactly what was done during this swap such as where the new motor came from and what year car it came out of?
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Customer reply replied 8 years ago
i had the timing checked and it was fine. i am not sure but i think the engine was not rebuilt and it is the same year and i dont know where it came from although i can ask my mechanic. it has less than 50k on it and another mechanic told me he heard and wasn;t certain he believed that in japan they swap in new engines after 50k and americans buy the old engines and sell them?
Customer reply replied 8 years ago
i did not get an answer and my deposit was charged to my card, even though i did not click on "accept answer". that didn't happen last time i used this website. i also never received a reply to my reply above. i require a reply until i am satisfied that i have received useful info, please.
Subaru Mechanic: wrxteck, Subaru Technician replied 8 years ago
I don't control how or when ur card gets charged and as far as a response I can't give you a good enough answer for the info you've given me. Most of the problems with an engine swap are created by whoever is doing the job. Are there any fault codes in the ECM?? How was the timing checked? I could give you a laundry list of possible things wrong and you still may have a problem. I'm sorry if I haven't helped you.
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Customer reply replied 8 years ago
please give me the laundry list. the timing was checked and i was told that every tooth was in place. i am not sure was fault codes in the ecm means, i will ask my mechanic about that. i doubt the engine was rebuilt as that would be too much of a risk and seems like a bad decision. the mechanic who did the swap is not someone i am wanting to be in contact with at this time so i am hesitant to call him. i have taken it to someone else to figure out how to get it running well. i am hesitant to call the first one because it took him 7 weeks to do the job. he gave it back to me 3 times and asked for more $ each time, and it still isn't running like it should be (lack of power). my current mechanic hasn't come up with the solution to the power problem and so i am asking you what you might suggest he look into at this point. any help at this juncture is much appreciated. i am wondering if i should be concerned about the transmission or exhaust as possible sources of the problem. before the swap it ran fine, passed smog, yet smelled fairly strongly of exhaust. it smells differently now, also passed smog - kinda like gas. it has no leaks.
Customer reply replied 8 years ago
request a reply to the above, please....gratitude...............
Customer reply replied 8 years ago
Relist: Incomplete answer.
i would like to please work with carguy1, who helped me the first time i used your website a few weeks ago. also, the first time i used this website, my card wasn't charged until i clicked accept answer, which i haven't yet, and my card was charged. i want to work with carguy1, yet i don't want to pay twice.
Customer reply replied 8 years ago
Relist: Incomplete answer.
still no response, engine lights have not come on, timing is fine....
Customer reply replied 8 years ago
Relist: Incomplete answer.
this is the 3rd time i am re-submitting my question. the first time i used this website i had to click "accept answer" for my dialogue to be complete. i was very satisfied and received comprehensive and meticulous information and guidance. this time, i never clicked "accept answer", never received a satisfactory answer, and my deposit was charged! rather inconsistent service! and unprofessional. too bad, as i thought i had found a good online resource. i would still like the answer i have inadvertently paid for, however. can we please try this again?
Customer reply replied 8 years ago
engine light is not on. was not a rebuilt engine. exhaust was tested - not the problem. excellent smog test. why reduced power at lower speeds?
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