P1514 error what is the real fix?

[louis]

I am running olsd and 24 lbs of boost. I can't seem to get past 2.33 g/sec before I see reduced power mode. I have seen one gentleman state this was his fix below. I also tried using dfe1 C6101 map but looks like that is for less modified cars. I have seen where wait4me suggested to max this table out so this is where I will be starting.

I am maxing out C6101 table, maxed out C3003 all to 105 kpa and added 65535 to C2903 even though I don't have a maf I read this was the fix for P1514 error.

One other gentleman suggested to lower the injector tables to stay below the 2.33 g/sec error and it worked for him. If the above changes do not help this may be my last resort I just hate changing manufacturer specs.

Traffic was heavy today but got right up to 2.12 g/sec for dyncylair_dma with no problem. I wasn't able to hit the troublesome g/sec at 2.33 but will post results as soon as I do.

Any others solved this yet running high boost?

[louis]

Just hit 2.33 grams/sec tonite and sure enough goes lean and reduced power mode. I would not bother trying any of these alleged fixes for this unless its a proven fix.

Would be nice if maybe the programmer of this software would direct us. This is a serious issue and seems a limitation with GM or the software has no work around.

Im parking this car now till someone spills the beans. This is not worth blowing $25,000.00 I have in my motor.

[joecar]

More info:
showthread.php?t=10332&highlight=P1514 (http://forum.efilive.com/showthread.php?t=10332&highlight=P1514)
showthread.php?t=9503&highlight=P1514 (http://forum.efilive.com/showthread.php?t=9503&highlight=P1514)

Don't try this just yet (let's get some feedback from other members):
what would happen if you set these:
- P1514 in C6001 to X:Not Reported,
- P1514 in C6002 to MIL.

[louis]

Thanks for the reply.

To be honest I dont want to try anything unless its a sure thing. When Im only at 60% throttle 4500 rpms and see 2.33 grams and afr goes to 17 or so then reduced power mode I freak out.

I redline at 7300 and 24 lbs of boost I cant imagine getting past this error without blowing it up.

I have tried almost everything posted here in every combination possible nothing fixed it.

I really have no other choice but to park it till there is a definite fix.

Please keep me posted on any good news regarding this P1514 error and someone out there who has a setup close to mine and I will continue to look every where I can also for a fix.

402 c.i. f1-C procharger, 24 lbs boost, 1250 hp blower and a 500 hp nitrous shot on top of the blower and I dont dare hit the nitrous till this is fixed

Thanks

[exploder]

I scaled my IFR tables and VE tables by about 20% and it fixed my problem....I tried all of the other things to fix it and none of them worked.

[louis]

Thanks for the info.

So you did not go by manufactured specs? What size injectors are you using?

Does this mean you estimated what your meth injection added on top of your injectors?

Please send more info I have a hard time going around manufactured specs but have seen another gentleman on this forum doing similar by fooling the pcm into thinking its getting less g/sec.

Do you get beyond the 2.33 g/sec for dyncylair_dma and did you tune in open loop speed density using map?

Thank you for your time

[exploder]

If you do a search under my name you will probably see what all I tried. It has been so long I don't really remember. What I did was use the redhardsupra IFR calculator for 96lb. injectors and put that in my IFR table. I then used auto ve to dial in the ve until the point where 1514 kicked in 2.33g/cyl. Then I just went back to my IFR table and the Auto ve and decreased both by an equal 20% value. This put me below the 1514 2.33g and it never threw a code again. I then tuned like normal and the world was right again. If you would like to talk about it you can reach me anytime day or night at 903-705-2886. It seriously won't bother me if you call me.

[5.7ute]

More info:
showthread.php?t=10332&highlight=P1514 (http://forum.efilive.com/showthread.php?t=10332&highlight=P1514)
showthread.php?t=9503&highlight=P1514 (http://forum.efilive.com/showthread.php?t=9503&highlight=P1514)

Don't try this just yet (let's get some feedback from other members):
what would happen if you set these:
- P1514 in C6001 to X:Not Reported,
- P1514 in C6002 to MIL.

I tried this with John a few years ago & it didnt help. I believe it still hit reduced power mode just didnt show up as a DTC.
IIRC the hard limits in the PCM are hit at 2.33G/sec & the only fix is to scale the VE/IFR tables to report a lower value. You must also remember that this will result in spark timing being referenced to a different cell in your tune & changes will need to be made to these tables to ensure safety.

[eficalibrator]

The 1514 code indicates that aircharge is beyond a safety limit as defined (in units of g/cyl) by a reference table. The reference table obviously has some max hexadecimal value that correlates to the 2.3g/cyl limit you're actually hitting at high torque.


I scaled my IFR tables and VE tables by about 20% and it fixed my problem....I tried all of the other things to fix it and none of them worked.
This is pretty much the solution. You need to make sure that the reported airmass per cylinder (g/cyl) from either the SD or MAF calcs does not exceed whatever's in the reference table. If the table is capped, you need to do the scaling exercise to stay within the limits. Chances are that you've already got some scaling to make the injectors or MAF work at this level, so just go a little further to make sure you're also not clipping the 1514 limit. (You can hit the 1514 limit based on SD calcs even if the MAF is disabled!)

Louis, this is part of what Geoff and Howard covered that weekend you ditched us. :angel_innocent:

[louis]

Hello and thank you all for the help here.

I am a statistics kind of guy so I have a few more questions and pretty sure I get what all are trying to say now.

Before I start I would like to comment here regarding ...

Louis, this is part of what Geoff and Howard covered that weekend you ditched us.

I actually thought I was being polite by separating all my issues so some one else could follow because it didn't relate to my title. I tend to add a lot of issues in one message.

I truly apologize if it looked that way but by no means did I intend to disrespect anyone. I honestly thought all would continue from there.

Equations help me a lot more sometimes so here goes.
In reference to this...

This is pretty much the solution. You need to make sure that the reported airmass per cylinder (g/cyl) from either the SD or MAF calcs does not exceed whatever's in the reference table. If the table is capped, you need to do the scaling exercise to stay within the limits. Chances are that you've already got some scaling to make the injectors or MAF work at this level, so just go a little further to make sure you're also not clipping the 1514 limit. (You can hit the 1514 limit based on SD calcs even if the MAF is disabled!)

So what I should assume is calculated air flow rate dynair, grams/sec. and my rpm divided by 15, divide both of them and that should equal what I should have for targeted dyncylair_dma value? i.e. logged dynair, (grams per sec)/(RPM/15) = targeted dyncylair_dma

A real live example in my logs at 2.05 for dyncylair_dma logging 4702 rpms and dynair being 511.99 equates to g/s (511.99)/(4702/15) 511.99 divided by 313.46 = targeted dyncylair_dma of 1.633?

If this is correct is there another way to reduce this besides changing manufactured specs on my injectors?

If I did lower the specs on ifr and ve would that also show higher percentage of injector duty cycle being used? Im concerned because at the rate I see now for 4700 rpm for injector duty cycle I see 63%. I can kick in my ethanol injector system to cover any issues but havent been able to hit that yet for tune because of this issue. I redline at 7300 and had ethanol set at approx 5500 along with the nitrous controller.

Glad the timing issue was brought to my attention also if I did reduce my ifr. I have taken out a lot of timing due to this issue.

Thank you all for the insight and I feel I am getting closer to firing this beast back up. Please keep the comments coming

[exploder]

I don't know the answer to how this all affects the IDC%. I personally don't worry about it because I have 96lb. injectors and a driver box plus 3 meth nozzles and 2 Bosch 044 pumps and I never get close to running out of fuel. Even if the IDC's were high after you scaled everything would it really even matter? It is only a calculation in the end and has no effect on the way the car runs. Hurry up and just scale your tables and be done with it. I want to see some numbers out of that thing.

[5.7ute]

Scaling will give you the same IDC as before, as it relates to the commanded pulsewidth versus RPM. Like exploder said just do it & get her cranking, just remember to keep an eye on your timing.

[eficalibrator]

Scaling will give you the same IDC as before, as it relates to the commanded pulsewidth versus RPM.
Precisely. :cheers:

Scaling just has the PCM computing a smaller fuel MASS for a smaller air MASS in the same ratio. The result should be the same injection time and hence, duty cycle, but with a lower estimated air mass that's below the max allowed limit in the 1514 table.

[louis]

Is this in essence detuning my car because of the pcm limitations?... Which is what I have been trying to avoid.

Scaling just has the PCM computing a smaller fuel MASS for a smaller air MASS in the same ratio. The result should be the same injection time and hence, duty cycle, but with a lower estimated air mass that's below the max allowed limit in the 1514 table. __________________

If so for me to take advantage of the larger air mass this is capable of using could I use a piggyback or standalone pcm to get around this? I hate the idea of detuning if that is the case because of hardware limitations and would gladly buy a whole new complete pcm system if I can get the maximum advantage here.

I have another corvette I run the fast system and no limitations there at all that I have seen. It is also 100 hp more than this one.

Thanks guys

[exploder]

Dude...your not detuning the car you just don't have enough resolution. The car is not going to go any faster or slower due to the scaling. It is what it is. Quit stalling or just buy BIG STUFF III and have another month down before you ever get it running and are out more money.

[louis]

Wow nice system and cheaper than fast.

Hardware limitations didnt tell me it was specifically a resolution issue. Now I understand. If I dont see specifics spelled out right in front of me I dig deeper till I get it thats all.

As far as wasting time Im not worried about time as long as I get all I can get out of this. I'll be giving it a go this weekend.

Great info by the way if you read from start to finish.

Thank you all.