F6

I've been trying for a couple of days now to get my AFR set to about 13.0-13.2 at WOT in all rpm ranges from 2600 rpm up to 6900 rpm.
The trouble I'm having is between 2600 and 3600 rpm. No matter what I do, it will stay at about 11.5 AFR.
I accelerate WOT from 2600 rpm up to fuel cut off, 6950 rpm.

I started out with –5% "PE % Change to Fuel/Air ratio vs. RPM" and still at –23% I still get 11.5 AFR….

2600 RPM… 11.5 AFR
2700 ………..11.4
2800 ……..…11.5
2900……….. 11.4
3000 ………. 11.5
3100 ………. 11.6
3200 ………. 11.7
3300 ………. 12.0
3400 ………. 12.2
3500 ……... 12.6
3600 ………. 13.1

MikeGyver

What are the coresponding values in the "PE % Change to Fuel/Air ratio vs. Coolant Temp" table?
And how are the fuel trims looking at idle, cruise, and acceleration? Could your fuel pressure be dropping with RPM?

F6

PE vs. Coolant Temp. is at 11 %, but it really doesn't matter as long as the engine is hot. The fuel pressure is great and so are all the other fuel trims, idle etc...
It's just that I can't get the AFR leaner from 2600--3600 rpm.

After more testing, I also see a discrepancy between 3rd or 4th gear WOT acceleration. I see much leaner values AFR 13.9 in 3rd gear than 11.5 AFR in 4th at 2800 rpm for example. Can't figure that out. It looks like only 3rd gear is reacting to -23% but not 4th.

WS6T3RROR

Plot afgs vs rpm and air fuel ratio, I think you'll figure out at that point the issue is that your maf sensor is out of cal a little bit. The part that makes me think that, is your info about changes in afr vs gears. You spend longer times at those airflow points in higher gears and transient issues like the maf being out of whack/rich at 200g/s have time to get cleared out.

F6

First, I don't have MAF, I have MAP..

Second, I also thought about spending longer times in 4th being more accurate than 3rd gear, that's why I tested both gears, many, many times. Strange is, why does 3rd gear respond to changes in PE vs. RPM and not 4th. It will always stay in 4th gear at 11.5 AFR no matter what I do!!!
I thought using 4th would be preciser than 3rd, but AFR values being so far apart is not normal. The values come very close or are identical once you get to >3600 rpm.

WS6T3RROR

How the hell would I know what you have, the year of your car/engine is not in your sig and you certainly didn't provide any info as to which fuel control scheme you were using.

The problem remains the same though, even with speed density. Its all in your tables, see what kind of map readings you're getting in third vs fourth gear and what kind of variation there is in the ve tables between those. Second of all for the 2500rpm issue since we're dealing with speed density and the issue is transient and we're talking at low rpm for wot. Look at the low map low rpm area that the car passes through in the ve table on its way to about 100kpa readings. Pull fuel from there and you should be able to get things in shape at low rpm.

That should be enough to get you headed in the right direction and thinking the right way. In reality there should be very little difference between gears if everything is doing its job.

The data you're taking for tuning this in should be at a very high rate something like 10hz or better if possible. Otherwise you will likely pass right over what you need to see.

Injuneer

Exactly.... I will never understand why people feel they do not have to provide the required info UP FRONT in their tech questions. Its like he thinks your the dumb one for not having a crystal ball.

F6

WS6T3RROR thanks for your info, I think you are right about the low VE-tables/MAP readings and I will look into this in the next few days. As always, good founded info from you.

But, I really don't know what the excitement is all about, just because I stated I'm using MAP and not MAF. Especially since the answer to the problem remains the same.....

Fred, I think your comment was absolutely unnecessary.. You once said, you weren't sure why so many people are leaving this board, "Advanced Tech" is practically dead, and you are one of the moderators. Well, read your comment again and I think you'll know why people are leaving. Do you really think people that ask questions can formulate and think of everything when asking a question??? A comment like, we need more info, would have been appropriate.

As a moderator you should try to appease and not stir up even more between the posters.

Injuneer

And you should try to provide the info up front... so people can help you, without wasting their time - very inconsiderate.

Normally, I would just ignore your personal attack, but since you seem to pull it out every time I offer suggestions..... I'll break my own rules and respond.

My comment was totally appropriate. You come here every once in a while, and always find fault with the people who try and help you. You do everything you can do to antagonize the people who are trying to help you, and are seldom appreciative of the help you get. You come across as demanding, condescending and inconsiderate.

You might want reflect a bit on yourself, rather than always criticizing and blaming others.

sbs

Sounds like there's some pre-history playing into this, but from where I sit this thread seemed fine until post #7.

#6 started rough, but the overall post was helpful.

Don't see any problems with the OP's posts...

F6

I have never had problems with anyone on this board and certainly not with Fred. I would suggest he opens his own thread and not use mine to find answers to the problems he seems to be having with quite a few members or should I say former members of this board.

Fred, if you have nothing positive to contribute to the question I had, then please stay out of my thread…

WS6T3RROR, I would like to apologize to you if I have offended you in any way with my direct answer in post # 5. You know it’s not always easy for someone not being an American and having to speak/write English. Finding the right words to ask a question or give an answer is not always easy for me
.
I do have an answer to your suggestion you made in post # 6. Well, it’s not MAP related. I did some more tests and this time starting with 2000 rpm WOT in 3rd and 4th gear.
Same MAP values in 3rd and 4th gear
2200 rpm 100.8 MAP
2500 rpm 101.5
3000 rpm 101.1
4000 rpm 100.8
4500 rpm 100.4

Injuneer

As a moderator, its my job to persuade people to provide enough info so that others can accurately respond, and not waste their time.

You condemn this board, and blame me for all its problems - i.e. "Advanced Tech" (yes, we have a history here - its always my fault that the smart people leave the site, etc., etc.). Yet when you have a tough question, you come here for an answer, and get it, often arguing with the people who are trying to help you. But you never come to help others. You are a "taker", not a "giver".

If you want to continue this debate in an open forum, it won't work, because I will drop out of this thread, and ignore it.

WS6T3RROR

Same map values with one 'frame' of data, or are you saying its consistent across the entire length of the sample. Are there any jags or variations during the event. My personal car has issues with the 2 and 4 cylinders pulling on the map sensor causing large variations in map readings especially at high rpm and full load.

Post the logs of data and the tune, and I might take a look for things I would consider to be an issue.

What kind of fuel pressure regulator do you have on the car? Stock?

F6

WS6T3RROR, would you mind if I send you my DataMaster log and C.A.T.S DA2L Files via PM??
I don't want to continue this thread since it is being used from someone for something it wasn't intended.

BTW, the fuel pressure regulator is from TPIS and I'm using 46 PSI throughout the tune without a vacuum hose connected.

WS6T3RROR

I'm not taking the issue to pm, this section is slow enough without making the troubleshooting/solution private. I am sure if you stop engaging Fred he will be perfectly content to let it go. I have spent too much of my time pm'ing people on here only to repeat it again later for someone else who needs to know the same thing.

You don't have a vacuum hose connected to a vacuum referenced fuel pressure regulator? Or you set it to that without the hose connected. Imo anything other than the stock fpr is trash.