I have a 5.3 with cam im currently on e85 and im having an issue were in cold start if you rev it it will back at intake lean my idle afr is 16-17 very lean ive already added fuel to ve and doesnt seem to help ive added 10% to open loop at it richined it out more but than it goes crazy and starts dieing out any ideas? Most responses ive gotten from other forums is it wasnt ment to be ran on e85 without flex fuel sensor has 42lb green giant walbro 255

 

 

Yeah, it sounds like it needs to be tuned properly... but without a posted tune file I'm completely guessing.

 

here is my current file

 

I will be nice since this is obviously your first attempt at tuning something. When you fail the MAF, the tune runs off the secondary VE table. If you ever see something that looks anything like what you have done to your main VE table, something is drastically wrong. And yes, it is a fool's errand if you are trying to run pump e85 without a content sensor. The percentage on pump blends varies too much. If you are running an actual constant 85% blend, it is doable. Also, why e85? The gains on an NA motor are mostly negligible unless you are running crazy high compression.

 

Copy that explains why their wouldnt be any changes when adjusting im going e85 cause its cheaper and also i had it tuned by sombody and always had issues with idle or it dying when reversing i had contacted him to re adjust it but never replied also had nitrous on it with 91

 

- What are the cam specs?
- You said E85, but is it truly always E85? Some locations vary, some don't. Tuning for straight E85 without a sensor as long as it doesn't vary is not a problem and has been done since E85 came out.

 

Its a truck norris 212/22x lift 552/552 i test the e85 it was 90% since i drive it local i find it more convenient for me because i always go to the gas stations but test it as well the privous tune wasnt too good i messeged the tuner cause i wanted him to put my timing back to all motor timing since i dont run nitrous anymore i have a 1988 camaro i put it on but that has holley system but this one always idled like crap would shut off also had knock retard when tuned by previous tuner

 

Now I see. You are doing the time honored tradition of finding a bad "tuner", and deciding to learn to do it for yourself. I went through that over 20 years ago, and I bet a lot of people that tune for themselves went through that same process. Just remember, the main VE won't do anything with the MAF failed on the stock operating system. You need to copy any changes you make over to the secondary VE for them to work. Just don't do that with the table you have right now, as it is fubared.

 

Copy ima put main ve at what it was before yea pretty much trying to do it on my own i mean its a 360k mile 5.3 dont matter if it blows. i gotta learn some how not bashing on my tuner but from cars ive seen him tune my tune could be better. But my camaro i prefer that to be done by somebody which it is its another tuner and runs very good tbh

 

The good news is that unless you run so pig rich you wash the rings, or run with way too much timing for a while, it is hard to really blow up a mild NA build from tuning errors. You would be amazed if you saw how bad some of the tunes are that run "pretty good". You are in a pretty good starting place to learn without hurting anything.

 

Yes you need the alcohol sensor unless you plan to run ONLY E85 and calibrate the controller accordingly... 16-17 AFR doesn't make sense for E85? I'm surprised it would even turn over at that AFR.

Stoich for pump gas is 14.7:1 whereas it's 9.8:1 for E85

The sensor reads the mixture of pump gas to E85 and interpolates what Stoich is. Right now you're so far off the mark the o2 sensors cannot learn how to adjust the mixture and keep your engine running. Also you're likely to be dangerously lean if you apply any load to the engine.

As far as flex injectors; E85 requires a richer air to fuel mixture, hence the higher flow injectors (FYI OEM Pumps are the same pressure, flex regulator is a 3 bar and pump gas is 4 bar though). If your build doesn't exceed say 85% on existing injector pulse width then your injectors are likely good enough.

 

I hate the dual VE table tune files. Just didn’t get along with them at all.