My Mode delay is set at 5000rpm. Am I understanding this correctly, is this the rpm that PE starts at wot? I have set it at 3000rpm accroding to my current launch rpm of 3500rpm on the spray. I want to make sure PE is enabled at this rpm. Anyone have experiance/knowledge/insight on this issue? Thanks in advance.

 

From the HPT help file:

Mode Delay RPM: PE mode is delayed if RPM is below this value.

Mine was set for 3200 stock in a 1998 A4.

 

Help file, that's like reading directions. Why do think the Z06 was at 5000rpm. Maybe for normal take offs, so you don't go rich and stumble? anyone else? Am I looking fo problems on the street?

 

well i know in my cal file it has the pe delay rpm which is set at 3500. But on top of that it has a timed delay depending on throttle position and then it has a pe delay bypass which is a set throttle position. So from what i get is even if the delay is set at 3500rpm but the bypass is set at 90% throttle the moment you go over 90% throttle it will be in PE anyways without a delay

 

The PE Mode Delay on my '03 Z06 is set at 5500. I may be incorrect, but it looks like it's an either/or to enter PE mode. Either all the conditions are met on the PE Mode delay and MAP or the Cold Power Enrich Enable %TPS Threshold vs. RPM condition is met assuming the ECT is less than the Hot Select Temp constant. Either 'condition' will put the PCM in PE mode.

I don't think setting your PE Mode Delay to 3500 will hurt street driving.

 

does it have a pe delay bypass? i belive yours would, mine does.

 

PE Delay is disabled in all car calibrations.

Changing these numbers doesn't affect anything.

 

Why aren't little tidbits of info like this mentioned in the help file if they are known?

 

405HP_Z06, I looked and mine is also a default of 5500rpm, my bad.

rcfast, No PE delay bypass, that I can't find.

Gameover, Can you ellaborate on your statement. It doesn't make sense to me. Are you saying that PE should be disabled while making calibrations or it is disabled while calibrating. Or, is it something else? Some say disable pe while tuning LTFT and some say no and only go to 4000rpm, but I think if you don't go wot it's out of the picuture anyway?

 

He is saying that it wouldn't matter of you enter 0 or 6000 or any number in the Mode Delay RPM field. The OS used on the cars do not use that parameter for entering PE mode. Only the % TPS vs RPM tables. Probably only applies to the trucks.

 

the editor is missing the actual PE Delay value (we plan to add it), however, on cars PE Delay is always set to 0, it is only very rarely used on some trucks.

 

Thanks, it's all making sense know.

 

Robert,
Some disable PE mode by tuning, but I see no reason to do so. Just make a conscious effort to NOT hit the throttle postion/RPM to put you in PE mode while SD tuning with fuel trims. Fuel triming is disabled in PE mode so that is true.

 

This is true, but remember that your car will also be in open loop mode at WOT. Your computer will use the richer of the two values between the Open Loop F/A table and the PE table.

For some reason, my trims are not locking at zero during WOT. This only started happening after I tried leaning out the PE table. I know it's not the OLFA table because its divisor is at 1.13 and my PE table is at 1.15. Still trying to figure this one out...

 

My PE fuel enrich x rpm is 1.203 at 800rpm, and TPS is 45*at 800rpm. Does this mean that at 3/4 throttle PE is enabled at 800rpm x 1.203 multiplier? So, you don't have to be wot to enable PE? A little confused, but just making sure what/why I am doing a step.

 

That is the Fuel multiplier for the rpm's in PE mode. The way it works is if all your tables are set how they should be it is 14.7/PEMULTIPLER=A/F. So if you have it set at 1.203 you would take that and divide 14.7 by it. So at 800 rpms with that PE setting your a/f SHOULD be 12.2 (14.7/1.203). This is in a perfect world or a stock car, if your VE or MAF table is off the multiplier won't work quite like that and your a/f can be leaner or richer than what the computer is trying to have as the a/f. The multiplier set's what a/f the computer try's to achieve during PE. However if other tables are off the computer won't be able to get it where it wants. So you should get your VE and MAF tables dialed in before you mess with the PE and these adjustments should be done with the monitoring of a wideband to provent engine damage and to get accurate tables. Hope that helps, Also there is a different table that determines what throttle position PE is enabled. Its something like PE enable tps threshold VS rpms

 

Ok, I am at the wrong table, will check.

I found, Hot Power Enrich Enable %TPS x RPM. Now, at 800rpm TPS says 45%. Does this mean at 45% throttle PE is enabled at above multiplier? If so it gets progressively easyer to turn PE on. Isn't this going to throw my LTFT off? So, PE does not have to be wot to activate?

 

Correct, you don't have to be at WOT to enable PE corrections. You have to be operating at a MAP value above the setting for PE Enable MAP (stock is 15). If that condition is met, it will reference the PE Enable %TPS vs. RPM table next to see if those conditions are met. Either the Hot or Cold can be checked, it depends on the ECT vs. the Hot Select Temp value. If you're below that value, it pulls from the Cold table and above is the Hot value. My temp setting is 284*F which means I'm always pulling from the Cold table. If you are above the %TPS for the RPM range your operating it, the computer should start Commanding Stoich / PE Enrichment V8 Mult vs. RPM. This behavior allows your computer to add fuel in PE mode before you ever reach WOT. Max torque occurs at a richer value than stoich...

This divisor can be overridden though if you switch into Open Loop mode. If this occurs (like at WOT), the richer value of the PE Enrichment V8 Mult vs. RPM table or the Open Loop F/A vs. ECT vs. MAP table will be used.

 

Also to answer another question.. Ltrim learning is disabled in PE mode

 

LS1sound, thanks, I kind of figured this was the way, but like to make sure I am understanding correctly, lots of freaking tables.