Fuel pump/ injector ???s
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Fuel pump/ injector ???s
So I'm preparing to boost my 1999 gsr. I recently installed a 255 walbro fuel pump and some rc 650 cc injectors. I'm leaving the car in the garage, and I just wanted to see if it would start. My problem is that since then I tried started the car but it wont catch idle. My fuel pump is working and my injectors are injecting fuel,but It just wont stay started. Could this be flooding it? possibly too much fuel? Id like to get some feed back from someone who has experience with this. thanks all much love.
#2
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Re: Fuel pump/ injector ???s
Even without the high pressure pump... You are dumping an additional %170 of the needed fuel in, if you are on a stock ECU.
#4
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Re: Fuel pump/ injector ???s
^^^ what they said. If you need to run it for any reason before you get the tune done, you can replace the stock injectors and it should run fine.
If you have a tuning system that will let you make adjustments (eg. Crome, S300 or Neptune RTP), you can add a trim for the new injectors on top of your stock map and it should run more or less OK.
If you have a tuning system that will let you make adjustments (eg. Crome, S300 or Neptune RTP), you can add a trim for the new injectors on top of your stock map and it should run more or less OK.
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Re: Fuel pump/ injector ???s
Sorry guys I forgot to say I'm running a chipped p28. So should I just unplug the injectors and crank it to burn the extra fuel?
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Re: Fuel pump/ injector ???s
^^^ what they said. If you need to run it for any reason before you get the tune done, you can replace the stock injectors and it should run fine.
If you have a tuning system that will let you make adjustments (eg. Crome, S300 or Neptune RTP), you can add a trim for the new injectors on top of your stock map and it should run more or less OK.
If you have a tuning system that will let you make adjustments (eg. Crome, S300 or Neptune RTP), you can add a trim for the new injectors on top of your stock map and it should run more or less OK.
#7
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Re: Fuel pump/ injector ???s
Short answer: Yeah, no problem.
Long answer: The fuel pump provides enough flow to keep the pressure regulator happy. The regulator is what determines the fuel pressure, so everything downstream of the regulator is the same pressure regardless of the max flow rate of the fuel pump. The reason for the larger fuel pump is when you ask the pump for a lot of fuel, the stock pump can't keep up. Below that level, the stock pump and the 255 are functionally no different.
The problem with changing the injectors is that the ECU tells the injectors how long to stay open, not how much fuel to add. If the injectors are larger and the ECU doesn't 'know' that, it will add too much fuel. Closed-loop can handle the problem within limits, but you're beyond those limits.
You run into the same problem if you change the fuel pressure regulator. So you can run the aftermarket pump without a tune, but only on the stock FPR and stock injectors.
Since you can't modify your chip yourself, replace the injectors with stock until you're ready to tune, if you need to run the car for any reason.
Long answer: The fuel pump provides enough flow to keep the pressure regulator happy. The regulator is what determines the fuel pressure, so everything downstream of the regulator is the same pressure regardless of the max flow rate of the fuel pump. The reason for the larger fuel pump is when you ask the pump for a lot of fuel, the stock pump can't keep up. Below that level, the stock pump and the 255 are functionally no different.
The problem with changing the injectors is that the ECU tells the injectors how long to stay open, not how much fuel to add. If the injectors are larger and the ECU doesn't 'know' that, it will add too much fuel. Closed-loop can handle the problem within limits, but you're beyond those limits.
You run into the same problem if you change the fuel pressure regulator. So you can run the aftermarket pump without a tune, but only on the stock FPR and stock injectors.
Since you can't modify your chip yourself, replace the injectors with stock until you're ready to tune, if you need to run the car for any reason.
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#8
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Re: Fuel pump/ injector ???s
Long answer: The fuel pump provides enough flow to keep the pressure regulator happy. The regulator is what determines the fuel pressure, so everything downstream of the regulator is the same pressure regardless of the max flow rate of the fuel pump. The reason for the larger fuel pump is when you ask the pump for a lot of fuel, the stock pump can't keep up. Below that level, the stock pump and the 255 are functionally no different.
To the OP, I would just run the stock injectors until you get tuned. If you can burn your own basemaps, you could burn one for the larger injectors.
#9
Man U FTW
Re: Fuel pump/ injector ???s
Did you do any research before turboing your car? This issue comes down to tuning. Either you have a rich basemap or no tuning system at all. I'm leaning toward the latter
Washing out cylinders with fuel is a concern for new engines only. After cross-honing a newly bored cylinder, the new rings must seat themselves through a gradual wearing down of those cross hatches. Adding a bunch of fuel lubricates the cylinder walls and prevents proper ring sealing.
Washing out cylinders with fuel is a concern for new engines only. After cross-honing a newly bored cylinder, the new rings must seat themselves through a gradual wearing down of those cross hatches. Adding a bunch of fuel lubricates the cylinder walls and prevents proper ring sealing.
#10
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Re: Fuel pump/ injector ???s
Get fuel pressure regulator with a gauge. then you'll be dumping way too much fuel without a proper tune. get it tuned.
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