Incorrect Axis In OL Fuel Tables

[swingtan]

Hi Guys,

I have another query on these OL fuel tables after talking with Hymey.

B0145, B0147 and B0148 are all multipliers for various conditions and effect the final commanded fuel. In the descriptions, the figures are all multiplied to the values in the tables B0141 to B0144, which works in EQ. These tables still work OK when using AFR's but the "seem" wrong. For example, multipliers greater than 1 will cause a richer mixture. But when working in AFR, a multiplier greater than 1 would result in a leaner mixture.

Is it possible to have these tables converted on the fly, like the others, when changing between EQ / Lambda and AFR? For example, if working with AFRs, the table values in B0145, B0146 and B0147, should be displayed as 1/(EQ multiplier). Does any of this make sense?

Simon.

[Blacky]

Hi Guys,

I have another query on these OL fuel tables after talking with Hymey.

B0145, B0147 and B0148 are all multipliers for various conditions and effect the final commanded fuel. In the descriptions, the figures are all multiplied to the values in the tables B0141 to B0144, which works in EQ. These tables still work OK when using AFR's but the "seem" wrong. For example, multipliers greater than 1 will cause a richer mixture. But when working in AFR, a multiplier greater than 1 would result in a leaner mixture.

Is it possible to have these tables converted on the fly, like the others, when changing between EQ / Lambda and AFR? For example, if working with AFRs, the table values in B0145, B0146 and B0147, should be displayed as 1/(EQ multiplier). Does any of this make sense?

Simon.

Fuel multipliers can ONLY be expressed in EQ Ratio (or Lambda I guess). They cannot be expressed in AFR. There is an explanation of why in Appendix-B of the Tuning Tool Manual.

Regards
Paul

[swingtan]

OK, I see the problem. I guess I'll just have to start thinking in EQ from now on

[joecar]

... I guess I'll just have to start thinking in EQ from now on

+1

[hymey]

I can see where it gets confusing. For instance it says the value of the cell is measured in lambda which is for instance .95x14.63=13.9:1 (it says lambda on the 3D picture) but in the text it explains the final result is in eq. but eq is 1/Lambda same result is 1.05.

The factors in the PE table are seen as lambda aswell. I am unsure why they use EQ in the open loop tables B0146,47, and 48 when it is lambda in B0141 and B0143. Is it possible to reverse it so that we use lambda(or simply multipliers) everywhere, it is much easier to work with.

Cheers

Joel

[hymey]

I have B0148 table working, I am trying to use this for lean cruise adjustment. I can command a richer idle say 14.0:1 but when I try to force it leaner it doesnt change anything. I can put in a very lean setting to see if its working but its not whereas in the same cells I command very rich and it runs rich. The formula for open loop hasn't been covered thoroughly either.

B0143 + (B0144 - B0143 x B0145) x B0146 x B0148. It is a simple formula but if you want to play with these tables you have to have your pen and paper out to get the final result you desire.

If you look at B0148 and B0146 tables it says to multiply to B0143 or B0141 to get final fuelling command but then we are leaving half the formula out. I believe the formula is
[B0143+(B0144-B0143xB0145)]x B0146 x B0148. So now
B0146 and B0148 can be multiplied to the final results of the left side of the formula not added.

[redhardsupra]

hymey, where did you get this formula from?

[hymey]

It states the formula in sections B0141 and B0143.

cheers

Joel