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Discussion Starter #1 (Edited)
So I just installed some ID1000's and I've got them dialed in pretty well and the LTFT and STFTs are within +- 5%.

I've noticed that when using the recommended latencies the car was EXTREMELY lean and almost dying, the AFRs were lean off the max of the wideband. I dramatically increased the latencies and it solved the problem and everything seems to run, well, about perfectly now. I'm just wondering if this is common or if this may be an indication of an issue with these injectors, my latencies are literally DOUBLE what the recommended manufacturer latencies are for these injectors. Moreover, they are double than the recommended latencies from a few threads I have found for Evos.

My cc/min is a bit higher than other people have used for these injectors but not by a large margin.

Anyone else experienced this with a car they have tuned?


I HAVE FIXED THIS ISSUE, SEE PAGE 2 FOR HOW TO FIX IT IF YOU ARE EXPERIENCING THIS PROBLEM.
 

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The first thing we need to know is exactly what your LTFT LOW and MID fuel trims actually are, so post up your exact fuel trims. Saying +/-5% is too broad of a description to clearly see if there is an error in the latencies. If you are +5% LOW and -5% MID, that's a 10% difference and can be dialed in better, just an example.

Latency adjustments help with the 'LINEARITY' of fuel delivery, while the injector scaling adjusts the overall VOLUME of fuel delivery. The latencies need to be dialed-in before the scaling can be dialed-in to its final settings.

So first, get your LOW and MID fuel trims as close to the same value as you can (doesn't matter what value it is right now, just get them as close to the same as possible).

If your LTFT LOW is higher than your LTFT MID, raise your latency values.

If your LTFT LOW is lower than your LTFT MID, lower your latency values.

Once you have your fuel trims closely matching one another, NOW you can dial-in your injector scaling to bring them closer to the 0% fuel trim mark. If both LTFT's are adding fuel (+), lower your injector scaling. If your LTFT's are removing fuel (-), raise your injector scaling.
 

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We did have to change the latencies when we fitted mine, was too lean also....... Sorry but can't remember what we settled on, about one stage less methinks
 

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Discussion Starter #4 (Edited)
The first thing we need to know is exactly what your LTFT LOW and MID fuel trims actually are, so post up your exact fuel trims. Saying +/-5% is too broad of a description to clearly see if there is an error in the latencies. If you are +5% LOW and -5% MID, that's a 10% difference and can be dialed in better, just an example.

Latency adjustments help with the 'LINEARITY' of fuel delivery, while the injector scaling adjusts the overall VOLUME of fuel delivery. The latencies need to be dialed-in before the scaling can be dialed-in to its final settings.

So first, get your LOW and MID fuel trims as close to the same value as you can (doesn't matter what value it is right now, just get them as close to the same as possible).

If your LTFT LOW is higher than your LTFT MID, raise your latency values.

If your LTFT LOW is lower than your LTFT MID, lower your latency values.

Once you have your fuel trims closely matching one another, NOW you can dial-in your injector scaling to bring them closer to the 0% fuel trim mark. If both LTFT's are adding fuel (+), lower your injector scaling. If your LTFT's are removing fuel (-), raise your injector scaling.
When I finished yesterday I had them both at ~ -4%. I raised my injector scaling to the next number available upwards (since it increments in groups more or less). I'm about to go out in a couple hours to see if this change will bring it closer to 0.

In Merlin's guide it's recommended to disconnect the alternator and drain the battery to ensure the fuel trims are still in line at lower voltages. Is this common practice - and - is there an easier way of doing this?
 

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Battery disconnect is std practice to reset fuel trims, only thing you'll lose is radio stations (well I do anyway)
 

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It is usually not necessary to disconnect the alternator to confirm the latencies are accurate at lower voltages if you started with the manufacturers suggested latencies. As long as you are changing all of the latency values at the same time (so the latency voltage curve stays the same), you should be dialed-in just fine once you get your latencies adjusted in the 13-14v range.
 

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right they are controlled by the ecu/tuning software, I was just trying to investigate if its an ID brand issue. (I feel like every time I post that I run ID1600s, E85 has to be mentioned or else I get at least 2 people posting/pm-ing me the recall of the injectors when run on 93) :/
 

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Battery disconnect is std practice to reset fuel trims, only thing you'll lose is radio stations (well I do anyway)
You don't need to disconnect the battery to reset the fuel trims. Just unplug fuse #2 in the underhood fuse panel for about 10 seconds and re-install. It is the main fuse for the stored memory in the ECU. This should save your radio settings :)

-Jamie
 

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Discussion Starter #12
Well I finished dialing them in and I got some weird results. I ended up with a scaling value of 770 and latencies of:

6.12
4.68
2.88
2.064
1.488
1.152
0.96

Nevertheless I got the LTFT Idle / Low around -1 to -2% over extended drives / time idling. I retuned the car and got the closed loop maps back in order with the new injectors and everything worked great!
 

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Discussion Starter #13
Ok so here is what I *really* ended up with. The previous numbers were off b/c my idle LTFT was not updating and caused me to have false confidence, the previous numbers had idle trim at approx -4 after all was said and done. The trims fluctuate to some degree, but the below numbers seem to show a consistent -.9 for cruise and around -1.17-> -2.1 for idle. I could probably get them a bit closer but I'm happy with the results to be honest. I may work on them a little later.

Scaling of 812

Latencies:

5.928
4.728
2.928
2.04
1.512
1.152
0.984
 

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latencies don't really affect AFR (at WOT anyways)

it's also better to start with a SCALING that is approximately correct (ie 900-1000), and then get your latencies dialed in...

once you have the TRIMS right, then you tune your Fuel Map (so initially richen it upto 10's and then lean out slowly)
 

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Discussion Starter #15
OK I HAVE FINALLY FIGURED THIS OUT!!!! WOOOHOOOOO!

There was an problem with my XML configuration that I had copied and pasted in from one of Golden's threads. Apparently he later went and updated this formula to be correct, but I still had this incorrect legacy formula. As a result this caused my latencies to appear to be dramatically higher than what they actually were:

To Fix this, if you are experiencing this issue - right click on the latency map in ecuflash, click edit map. Then click the "scalings..." button. Check the "latency scaling" formula and make sure it is x*0.015. Mine was set to x*0.024. Upon changing the formula my latencies automatically updated with the below info:

Final results - Scaling 812.

Latencies:
3.705
2.955
1.83
1.275
0.945
0.72
0.615


This is great validation to me, despite being fed the wrong data, I was able to use my logs and patience to get these bastards where they need to be. It's great to know that, after fixing the formula, my numbers are now much more in line with what other people have witnessed with these injectors. I was doubly concerned b/c I bought these injectors used and was concerned about other issues. Finally I can sleep in peace!
 

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Discussion Starter #17
Tephra, I'd like to thank you for discovering the correct formula, I was informed in a PM that you came up with the x*0.015 formula =]
 

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Final results - Scaling 812.

Latencies:
3.705
2.955
1.83
1.275
0.945
0.72
0.615
Thats close to what I've figured out. However, due to bigger pump and slightly higher fuel pressure, scaling for me is 1042. But the lag times seem to work quite well. Thank you for this!

Emma :D
 
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