NZ951

Hey,

The red +/- in your sheet that you notify as changes, in what unit is that in? In all cells I have values that range from 99 to 150, are you saying that in cell 38 for example you increased what I have at 104 to 154?

OZ951

The +/- changes are percentage changes, so my cell 38 which says +50 is going to add 50% more fuel than would have been provided by the original fuel map in the DME chip.

I'm not sure why your numbers range from 99-150 but I see that your system is a link II and rather than the Link AFM (MAP) and I am not that familiar with it, so it may just be programmed with differently. I did dig up a copy of a Link EMS manual though and it does say that the fuel zones range from 0-99. I will go and see if I can program a fuel zone to be greater than 99 just for interest sake.

Cheers.

'86 944 turbo

Its good to see you back Danno. I thought we lost you there.

B951S

Oz951
I posted this in another thead and I think you answered it here. I was real interestred to learn you can force the DME into open loop with a resistor accross the alt sensor. Should this be removed after tuning or could I hook up a circuit to switch the DME in and out of closed loop as required and ditch the alt sensor altogether? I must say, you input here is extremely valuable, and your website is great!

OZ951

B 951S, I expect that there is a switch type that would provide you the ability to switch between a resistor and the alt sensor I am not an electrical expert though so I couldnt tell you what it is. A knowledgeable assistant at an electronics component store could probably point you to the right switch if you describe what your trying to achieve.

I havent decided yet whether to leave the car in open loop or not, once I have refined the tuning on a dyno I will compare the driveability with the car in open loop and closed loop and then decide which way I will leave it.


Oh BTW I updated the document and the picture of the zone worksheet

Pauerman

OZ - how do you create those graphs from the datalogged info that's viewed through EXCEL?

If I tune my car in open loop with the resistor, will the settings be inaccurate if I return the car to closed loop?

Thanks for you help - very informative thread.

Pauerman

OZ - is it necessary to cap off the idle stabilizer or can you just deactivate it by jumpering pins B & C at the test port?

OZ951

Pauerman,

Going back to closed loop should not cause any problems. The fuel will be based on the deltas in the zone worksheet and in closed loop the DME will monitor the fuel via the O2 sensor, if the o2 sensor tells the DME that the fuel is rich at that instant the DME will reduce the fuel slightly... then the O2 will tell the DME that the mixture is now a bit lean and the DME will command more fuel.....this goes on and on continuously and is why the AF gauge can be seen to dither backwards and forwards when in closed loop.

As for the ISV I capped off the port at the manifold so that I could be sure there were no leaks in that area at all and no leaks through the ISV itself. Note that I still put the ISV hose back on the capped port so that the intake system was complete. The pin B & C jumper idea does ring a bell but I didnt try it due to the aforementioned reasons.

I hope the thread helps you to get your fuel sorted out a bit better.

Edit - To make the graphs is straightforward if you are familiar with Excel, you import the data and then remove the headings and blank rows.

Import data (space delimited)
Delete header rows
number the rows from 1 to whatever (creates an index that you can later sort on)
Sort on the RPM field
all the rows that say RPM TPS AFM..... etc will now be at the bottom of the data and all the blank rows will have been removed.
Delete the RPM TPS....etc. header lines
Sort the data on the index column of numbers that you added.
Now select all columns except the index column
click the graph icon
Click line graph (no markers)
after the graph is created right click the RPM data and format the data series to go on the secondary axis, that will make the scale for everything else a lot more readable.
I usually delete the Vecu and gain series plus anything else that I am not watching.

Pauerman

Thanks OZ

I'm off to Radio Shack for a resistor. Does it matter if it's a 1/4 or 1/2 watt or should it be something different?

OZ951

It doesnt matter.

B951S

Slightly off topic, but I just recieved my MAP 2 kit from Dan and wondered how I would get the serial link working?? Is there some software I need to download, etc?

Thanks

OZ951

You can get it here Directory containing Comlink right click and save as...

It is very basic, runs in a dos window. The log displays on teh screen as the engien runs. You save teh data to a file by pressing F2 and giving a file name. Be sure to close the file (F3) prior to terminating the program.

NZ951

Has anyone got Link 2 fuel values yet?

Pauerman

OZ - I've just installed a 1.8K ohm resistor across the DME side of the connector that goes to a round Nippon Denso sensor part #944 606 151 00. Is this the altitude sensor?

I've bypassed my ISV, but my o2 readings on my handheld programmer is still dittering. With the system in open loop is the o2 output signal stable or does it still dither slightly cause that's what mine is doing?

OZ951

Pauerman,

your AF readout could still appear to be dithering if the MAP is switching between zones and the fuel mixtures are substantially different in the zones it is switching between. Is the RPM stable ? when you rev to certain points does the AF gauge dither continuously ? Every time you back off the throttle the gauge will go to lean also.