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Discussion Starter · #1 ·
So first some back story, this was my teenage brothers first manual/performance/project car. Bought it 2 years ago in very good shape just under 100k miles. Drove it 4-5k miles with 0 issues and then installed a fancy piston window in the block. So we decided to go the route of a like for like engine swap, his first major mechanical project besides general maintenance. I helped a bit but most of my experience is old fords and civics, he also had several other decently knowledgeable and experienced friends helps too. He is no idiot so I have faith it was done for the most part correctly. So a few months of labor, imported under 40k miles engine, a header back exhaust, lightweight pulleys, lowering springs, an oil catch can and a couple alternators later he has a running car again. Long story short its mine now after barely 2k miles post swap and I'm not allowed to get rid of it.
One thing neither of us have been able to figure out is that ever since the swap it runs really rich (avg 14-17 mpg with a strong fuel smell) and is pretty low on power compared to previously. I can barely hit 80mph on a long flat straight, though getting to 60 isn't bad just no guts in 5th and 6th. It runs pretty reliably besides that. Due to all my other vehicles going down, I have had to put a few hundred miles on it but with no issue except it guzzling premium in this economy. I have gone thru the engine myself, its not throwing any codes and everything looks right but no mechanic in my area will touch it because they don't want to be liable for the non pro engine swap. so I am either given the absurd prices or just flat out turned away. I am thinking its timing related or ECU or both but not sure at all. I have never messed with tuning an ECU but am willing to learn and try but would need some resources if that's the road I need to go down. Anybody have any ideas as to what the solution would be?
 

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Discussion Starter · #4 ·
if it's really running that rich, you should have some codes. what are you using to scan it? Did you swap the original injectors or they are bigger?
Used the jdm engines injectors, an older model harbor freight obd reader, never failed me before. And it is really running that rich, I am luck to get 200 miles to a full tank
 

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Sounds like it might be a qr20 instead of a qr25, this is what jumps out to me.
he said the injectors that came with the swap were used, assuming those were stock, I don't think that's the right path. The ECU will typically throw codes related to faulty conditions: MAF, TB, O2. Those would be the main culprits for excessive fuel. Another option could be timing, verify the cams are lined up, the timing chain hasn't skipped any teeth.
 

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As much as I'd hate to throw money at it, I'd say get uprev and throw a few tunes at it. The og ECU is aggressive due to the SpecV. It seriously throws fuel in there. A detune sounds in order to get better milage. I have no idea why you can't hit 80. Qr20, or qr25, top end shouldn't matter.
 

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Just talking here... mine loves gas, eats it right up. The getting to 80 is what's got me.
I keep wanting to think it can't breathe.
Is there anything causing restriction with air flow.
 
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