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You also mentioned earlier that the fitting on top of the pump for the return is just threaded straight in, is it possible its leaking fuel under pressure? Could be a fuel leak at the pump causing the smell and bad MPG.

I would have thought the OEM ECU would have measured the excessive o2 readings and either "learned" and adjusted the injector pulse or given a cel?
It would try and do this by reducing the voltage being applied to the pump thinking that will solve the rich scenario. However, being a pump that flows more at EVERY voltage value, that new pump will still be delivering more fuel than the stock one.
 

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Discussion Starter #42
You also mentioned earlier that the fitting on top of the pump for the return is just threaded straight in, is it possible its leaking fuel under pressure? Could be a fuel leak at the pump causing the smell and bad MPG.

I would have thought the OEM ECU would have measured the excessive o2 readings and either "learned" and adjusted the injector pulse or given a cel?
I'm gonna have the wifey press the gas while i look at the fitting. Thx for ur input
 

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Somethings not right if your mileage is halved...I’m thinking you have a pretty big leak/evaporation loss. I’m on 1050cc (stocks are like 280cc) injectors and staged dual 320 lph fuel pumps and I average 14-15 mpg combined. Stock mileage is like 18. If your car was truly consuming that much fuel I think you’d have liquid fuel in the cylinders/be “making” oil. Maybe not, but that’s why I think it’s a leak.

I don’t think the ecu will modulate the fuel pump voltage based on fuel trims. It’ll either run the pump at 9v or 12v and it’s based on throttle position. I would jump the resistor out and run 12v all the time. It won’t affect anything besides the life of the pump.

Do you have an OBD2 reader? You can check your STFT and LTFT. That’ll show real quick if you’re rich/lean. You need a reader anyway to get your FIC tuned in the vacuum/transition areas.

The XS kit didn’t come with a midpipe, unless they’ve added one. You’ll have to custom make one for between the downpipe and catback. CX comes with midpipe but I don’t know if it’ll fit XS hardware.
 

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I don’t think the ecu will modulate the fuel pump voltage based on fuel trims. It’ll either run the pump at 9v or 12v and it’s based on throttle position. I would jump the resistor out and run 12v all the time.
Oh is that how these things work? It’s only 9v or 12v? I thought it was infinitely variable. Maybe there is an exaggeration of actual MPG? Probably running rich.
 

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Discussion Starter #45
Somethings not right if your mileage is halved...I’m thinking you have a pretty big leak/evaporation loss. I’m on 1050cc (stocks are like 280cc) injectors and staged dual 320 lph fuel pumps and I average 14-15 mpg combined. Stock mileage is like 18. If your car was truly consuming that much fuel I think you’d have liquid fuel in the cylinders/be “making” oil. Maybe not, but that’s why I think it’s a leak.

I don’t think the ecu will modulate the fuel pump voltage based on fuel trims. It’ll either run the pump at 9v or 12v and it’s based on throttle position. I would jump the resistor out and run 12v all the time. It won’t affect anything besides the life of the pump.

Do you have an OBD2 reader? You can check your STFT and LTFT. That’ll show real quick if you’re rich/lean. You need a reader anyway to get your FIC tuned in the vacuum/transition areas.

The XS kit didn’t come with a midpipe, unless they’ve added one. You’ll have to custom make one for between the downpipe and catback. CX comes with midpipe but I don’t know if it’ll fit XS hardware.
I have an OBD2 and the Torque app. It says my STFT and LTFT are within 5% of 0 (which i understand is good/normal)
It also says that i'm getting ~21 mpg.

I suppose this indicates a leak.

--

Also, I decided to change my valve cover gaskets, sparkplugs, and paint my valve cover gaskets that "wrinkle black". Very excited and will have pics of the job within the week :)
 

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Discussion Starter #47
136794


Ya she leaky. This wiring harness is the most brittle thing I've worked with.. jeeze..
 

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Discussion Starter #50
Performance plugs, oil leak, and beautification. I want to do this whole thing cheap, but I also dont want to turn my car into a leaky POS
 

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Discussion Starter #52
So XS power just sent methis exhaust manifold. Theu say I can get the 3mm nicer one for an extra 100 bucks.

My question is... is it worth it to get the slightly thicker manifold? Or should I just roll with this one? Thx.
136804
 

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The question is, what thickness is the one you have? 3mm is steam pipe territory, great if you are planning on going high pressure and temperature but Im not sure if its essential for a low boost NA-T setup. A lot will depend on what wall thickness the pipes are on that manifold and the quality of the welds and steels used, but given that plenty of people have used the standard XS manifolds and i havent read about any issues (not that i have been looking) i would imagine it should be fine.

Its so purty and shiney...🤤
 

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I had to use some RTV in the groove to get mine to seal as it miss matched a little.... can you get bright blue RTV...? :LOL:

Nice to see it all coming along step by step, progress is progress. Your partner must be quite forgiving, so far most photos are on or near the carpet. Not sure mine would be impressed with car parts in the house or near the carpet ;)
 
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