This only happened after we drained the tank and put in the E85 and started tuning. I made some injector scaling changes and left the boost the same and the fuel and timing maps alone to see where the a/f's were from the previous 91 tune to the E85 change. First pull it was in the 9.9's until redline, when it suddenly jumped to 14.4's. Next pull w/o changing anything it was in the 14.4's for the entire run. Continued to tweak the fuel map and scaling to get the a/f's acceptable at the same boost level (21psi) to start with and was able to get them to mid 11's at peak torque and it wouldn't be any less than 13.3's at redline. This was with 22ms pulsewidth on the injectors from peak torque to redline.

The known good runs on 91 octane we tweaked out that were flat 11.3's to redline had 11.3ms pulsewidth @ peak torque and 9ms at redline. This was all before the change to E85. Everything mechanically stayed the same from the 91 tune to the E85 tune. 1200cc injectors, dual fuel pump setup, external fuel filter, etc. were all installed before tuning on 91 octane.

The reason the IPW is the same now on the 91 tune is because that was the final map made for that fuel with 11.3 afr's. Now with what changed during the E85 tune mechanically, is the reason the afr's are in the 16's with the same pulsewidth being applied from the ecu.

Razorlab, it's not impossible for the tune to jump to the 16's in afr's if i'm commading the same IPW's on the 91 tune as before if the FPR is bad and I'm not getting the proper fuel pressure; ~60+psi. Yes I could tune this out with just pulsewidth/duty cycle on 1200's and dual pumps on 91 octane....but that's a bandaid fix as I know something changed mechanically otherwise the afr's wouldn't be so drastically different as 5 points leaner.

I've bypassed the Fuel Pressure solenoid as well and ran the vac. line direct from the manifold to the FPR with no change.

 

I'm just confused now. You keep throwing around all these different IPW's I don't know what is what anymore. You said 9ms before at redline, now you are saying 22ms at redline.... 22ms at 7k is almost 130% IDC.

I take it you have checked your inline filter?

I had a problem where my AFR's suddenly leaned out from 11.8 to 14.4 at WOT. Ended up being my fuel filter was clogged.

 

The 22ms of IPW's was on the E85 tune, not on the 91 tune as the 91 tune didn't have an issue.

Yes, we removed the inline filter to see if it would change anything and it was still lean. Only fuel filter in the system now is the one provided with the Full-Blown dual pump setup inline before the rail, as the factory fuel hanger with the filter built-in was removed.

 

Almost sounds like your pumps are bypassing in the tank. I would assume that duals with 1200s on gas would be enough that it would tune. Its easier to see a log or to have the IDC numbers since very few here think or log in terms of IPW generally.

 

Ok,

So have you gone back to 91 oct? And everything is ok again with 91? No fueling issues?

If so...

What are you scaling the injectors to when you switch to E85? They should be scaled approx 70% down. For example, 1000cc injectors scaled at 860 for gas should be scaled down to approx 580 for E85

 

I had the exact same problem! Same rpm and everything.
I did 3 differnt maps. 91,e85, and c16. The 91 and c16 maps
had no problems at all. When we put in the e85 the a/f's started
to climb at around 5500 rpm up to around 13.0.
I think it has something to do with the fuel system..
I have the AMS 1000 hp fuel system and stock ecu with 1000cc inj.
Still have no idea what the problem is?

 

I would assume that if they are bypassing in the tank they would do it from the beginning of tuning. Reason being the 91 tune went fine with no problems, then with E85 I'm having to keep the injector open completely to try and have acceptable afr's. Then put 91 octane back in, with the known good tune I just did, and now afr's are in the 16's with the same IPW's and boost that had 11.3's from peak torque to redline.

With one single walbro I've tuned out cars to 450whp on E85.

 

Dude, are you reading what I even type? Not trying to come off like an a$$, but I've posted it many times that I've switched back to the 91 tune we just did the same day where afr's were perfect (11.3's) and now with the same IPW's from that tune the afr's are in the 16's. This is all after the issues arose on the E85.

Yes I scaled the injectors back 30% in the map for the switch to E85 for a starting point for tuning.

 

God I love when people come in asking for help and get all pissed when they don't hear what they want.

If you wrote your posts in a easy to read way instead of different IPW's flying all over the place (example being you said IPW was 9ms for both 91 and E85 then later you said it was 22ms for E85), I would understand them easier and not re-ask questions.

Sorry for trying to help. Good luck.

 

I'm not looking for help, I just posted factual information that the owner of the vehicle left out as he was unaware of it. When the car comes back I know what I am going to replace mechanially and work from there as I know it's nothing to do with the ecu and injector scaling.

If you re-read what I posted multiple times you will be able to see that the 91 tune has not been altered since it was tuned first with the IPW's of 11.3ms at peak torque and 9ms at redline; as the car didn't experience an issue on the 91 tune only when we started tuning on E85. Thus the need for IPW's of 22ms on E85 to get the afr's to a respectable number, which was still mid 13 afr's at redline. Then drain the tank of E85, put 91 octane back in, load up the 91 tune saved from ealier dynoing with the 11.3ms @ peak torque and 9ms at redline and it is now in the 16's for afr's.

If you go back to post #9 in this thread on page one you will see that I only threw out 3 pulsewidth numbers from the begining. The 11.3ms @ peak torque and 9ms @ redline on the 91 tune. And then the 22ms I was commanding on the E85 tune to try and get the afr's in check.

 

according to the title of your thread, you are

 

LOL, did I make the post?

This isn't my first rodeo

FYI, you may want to do a search for my username as it may come in handy for you to get your AEM UEGO to read properly in your AEM EMS.

 

Exactly and the IDC's were in the low 80s with 1200s ( I have done that one as well...even double checked a log to make sure I wasnt lying).

However what I was trying to say is that as the fuel demands go up right about 5500 (where you notice the fuel pressure drop the most, or conversely where it will richen up with a bigger pump) is right where you are having the issue. To me its like the guy that throws a 255 in without the install kit and gets the same exact symptoms. I have a full blown unit but I havent looked at it in awhile. Do they need something similar to keep the pump tight against the top nipple or is it machined to fit tight to begin with? In the aforementioned case thats where it bypasses and since you have 2 pumps AND 1200s I really doubt you would have noticed it on gasoline since you'd never run out of fuel for the amount of boost you can run on 91.

It sounds like either an FPR issue or a pump issue to me.

 

kcevo didnt start the thread.

 

I aggree..
I did 3 maps on my car: 91, e85, and c16.. the afr only went up on e85.
There is a big difference in the amount of fuel being used when on e85.
Ill have to check the pump and make sure they are on right.