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Tuned ECU, lean, help!!!


Diamonds

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K, got my ECU from jason (Emance)

 

Im running a Redtop SR in an s14. Stock SR with T28, 550 topfeed RC injectors, stock MAFS, z32 fuel filter, walboro 255.

 

 

At full boost it seems to hit the 12.5 area but then wanders to 15.5 and sometimes even 16.5 (fluttering).

 

I'm using an innovate wideband (very accurate) that was previously used on my old setup which was super duper rich.

 

 

 

 

Thoughts and opinions? Why is it so lean?

 

is the problem fuel delivery?

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Emance...

 

I'm going to start out with a new filter. Then if that doesnt work... Tuen down the boost... Then new fuel pump. Then injectors. What other fuel components could it be?

 

Sorry i dont know anything about Emance. I do know Nistune and Nismotronic and calumsult.

 

Start with this if its tuned to a desired psi (say 15psi) if you go over 15 it will lean out since the tune doesnt compensate. I would start here. it needs to be logged so you can pin point the issue it could be a Pegged Maf, to high of injector duty, pump maxxing out etc.

 

And an answear to Alex's question would help also.

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Just an FYI, when those sensors fail, they drift lean. The innovate actually does a horrible job controlling the heaters on the sensors which is what leads to early failure. Thats why most of the "cheap" widebands have issues (The heater control). I would get a new sensor and make sure you have good data first.
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^^^ Good idea... BECAUSE, the care was running SUUUPER rich for a long time (8 months). Im serious, when i bought it a month ago and was driving it it was pegged at 7.4 at times. the previous owner did bigger power upgrades without ever getting a new tune.

 

 

 

Alex, i dont know what that means.

 

the car does have a FPR under the hood with gauge....

 

on the left

 

http://i822.photobucket.com/albums/zz143/TransporterRaphy/240sx/IMG00111-20101020-1808.jpg

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could be leaking from those metal rings in the intake. I know when I first put together some top feed rail kits for mototron injectors we had that issue, welding them in the intake fixed it. for the bosch top feed injectors i put them down in the stock orings
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try re calibrating your o2 sensor. its simple with an innovate.

1. unplug the sensor and turn the key forward for a minute.

2. turn key off and remove o2 sensor from the exhaust, then plug it back in.

3. while the o2 sensor is out in open air and plugged in, turn your key forward, this will calibrate your o2 sensor. once the gauge stops flashing (takes about a minute) turn the key off.

4. screw o2 sensor back into exhaust

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before buying a new wb02, check signal voltage, and if thats good try swapping it out with another known good sensor before dropping 65$ on a new one. if youre ever in dayton i can pop my LM1 in it and check

 

$65 is much cheaper than a new engine. Why even consider risking it? It sounds like his sensor is over a year old and they do NOT last that long and remain accurate on a LM1.

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$65 is much cheaper than a new engine. Why even consider risking it? It sounds like his sensor is over a year old and they do NOT last that long and remain accurate on a LM1.

 

ive had my lm1 for 3 years in about 12 different cars and my lc1 for 5 years in 3 different cars (runnning leaded race gas occasionally) both on their same sensors working flawlessly, only varying ~0.1 from a dyno dynamics wb02. but yes, it might be bad, but also simple diag work would prove so, instead of just throwing parts at the problem

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Update. So today. I removed the boost controller (because the boost was wandering between 15-18).

 

BAM, car pegs a 13.5 AFR all the way through the powerband... At 8 pounds... (though, at 8 pounds I'd expect mid11 AFR.

 

Tomorrow I will install a fuel pressure gauge and do some more pulls at 8 psi... To see if the fuel pressure raises with boost.

 

What is your synopsis after this update?

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Wait, at 8psi it is running 13.5 afr? That isn't rich. I'd rather see low 12 to high 11. I really don't see it pegging MAF since its the stock turbo and MAF. From factory, doesnt it run 8-12.5 psi? I can't remember. I think the one in my garage is putting out 8psi factory set (so I believe factory set). That engine easily did 11-12 afr on stock t28, MAF, stock injectors, and stock fpr at 12psi. Might want to double check wideband, fuel pressure under boost, and possible small vacuum leak. Though seems odd that it ran richer, at points, before on higher boost and no boost controller.

 

And about the boost referencing fpr, it is a regulator that increases pressure when under boost. They can vary in different ratios from 1:1 to like 15:1, meaning that for every psi of boost, it could increase fuel pressure 15psi. Normally those high ratios are used on cars with stock fuel maps/injectors (poor boy fuel "tuning"). Now about your Walbro pump, is it the high pressure one or low pressure pump?

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Wait, at 8psi it is running 13.5 afr? That isn't rich. I'd rather see low 12 to high 11. I really don't see it pegging MAF since its the stock turbo and MAF. From factory, doesnt it run 8-12.5 psi? I can't remember. I think the one in my garage is putting out 8psi factory set (so I believe factory set). That engine easily did 11-12 afr on stock t28, MAF, stock injectors, and stock fpr at 12psi. Might want to double check wideband, fuel pressure under boost, and possible small vacuum leak. Though seems odd that it ran richer, at points, before on higher boost and no boost controller.

 

And about the boost referencing fpr, it is a regulator that increases pressure when under boost. They can vary in different ratios from 1:1 to like 15:1, meaning that for every psi of boost, it could increase fuel pressure 15psi. Normally those high ratios are used on cars with stock fuel maps/injectors (poor boy fuel "tuning"). Now about your Walbro pump, is it the high pressure one or low pressure pump?

 

13.5 is rather lean in boost. it's not a stock turbo, and i assume youre probably running a soch maf, which contrary to popular belief, has a different transfer function than the actual sr maf. which t28 turbo are you running(s14 t28, s15 t28, s15 t28r, gt28rs)? also what is base fuel pressure set at? I believe stock is 43-45 without vaccum. jump your fuel pump relay and check it. that fpr you have looks rather chincy. I'd investigate it further. i still think the lower injector bosses you have could be leaking (ive seen it happen on every sr we've tuned/worked on without them being welded in). crank fuel pressure up to 48-50psi base and see what afr's are? the emance tune is a decent one. the few cars ive worked with, with the emance mail order tunes have been pretty close, the timing maps are rather conservative though. I would check everything over (boost leaks, FP, etc) and see where you are from there.

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