[RESOLVED] 510cc injectors made me have lean A/F

[viperlp01]

I just bought evo 3 510s and i installed them. I had no problem starting the car and it idles fine. On my 450s i have perfect idle on my narrowband; bouncing from rich to lean. When i installed these i am always lean and when i go WOT i don't go that deep into the rich. With my 450s i went about 90% into my narrowband and with the 510s i only go like 80%. By the way i havent got the SAFCII yet. I am in the process and i just tried to run these injectors stock and see what it does.

 

[architechnik]

Changing the injectors requires more than just a hot swap. To correctly account for the change in fuel you will need to use a wide band O2 sensor, as the narrowband bouncing around does little to give accurate readings. Likewise, assuming you purchased the correct injectors from a respectable shop, you may not even be running the correct fuel pressure which will cause a poor spray pattern.

So, the first thing you'll need to purchase or borrow from someone is a wideband O2. There is no tuning that can be done on a narrowband other than "yes the car can idle." When you get the afc, you can do some dialing in based on the overall modifications you have.

All-in-all, the narrowband just isn't a reliable start and if you start messing with things to get the narrowband to match previous readings you may mess up more than intended.

 

[silver bullit]

Do you have any fuel mods or management tuning to control the injectors or a/f?

 

[viperlp01]

I just personally thought that i should run richer mainly because of the same signal to injectors but bigger openings and i am only increaseing the size 60ccs. I am going to put the stock back on until i get the safc. The narrowband gives me an idea of the a/f. I told you guys that. I guess that a stock fpr will not keep up with the added loss of fuel. Maybe im not keeping a good pressure. I will do more research when i get all the things.

 

[RiceKiller_TSi]

Make sure you actually purchased 510's cause you should be running at least a little richer than the stock 450's. Like mentioned before those injectors may only be 510cc at a higher than stock fuel pressure for instance like 53psi.

 

[viperlp01]

I dk. They are yellow tops and say 510cc's. Perfect fit on my car. All i can say. I thought i was going to be richer as well.

 

[Mikael SS]

all a narrowband O2 will tell you is richer/leaner than 14.7

you may think you can tell something from it, but you're fooling yourself

 

[viperlp01]

You guys weren't listening to me obviously. I said i was running perfect with the 450s. bouncing back and forth. That is reading 14.7. The 510's are reading lower than 14.7 so it is running for sure leaner. But the good news is i found the culprit. I accidently double sealled the bottom rinds that go into the ports. duh(it is embarrasing) I think that is what it is. Now i have a leaky upper seal. And it take a day to get them in from anywhere. Is there any alterantive??

 

[drewvr4]

You guys weren't listening to me obviously. I said i was running perfect with the 450s. bouncing back and forth. That is reading 14.7. The 510's are reading lower than 14.7 so it is running for sure leaner. But the good news is i found the culprit. I accidently double sealled the bottom rinds that go into the ports. duh(it is embarrasing) I think that is what it is. Now i have a leaky upper seal. And it take a day to get them in from anywhere. Is there any alterantive??

ive never seen a lowband give out a/f numbers, where are you seeing that from?

The fact is you need to get a wideband and something to tune with, complaining because it doesn't run richer then your stock injectors is a worthless point. You need to do some other things first.