The car doesn't want to catch itself at idle from higher RPM

[mlecy]

The car (14 GT500 modified) doesn't want to catch itself very well when warm on coming down from high RPM. I have been messing with the P/N table under the Idle section but doesn't seem to be helping a lot. Is there another table I should be looking at or adjusting. Sometimes it will catch itself at 500 other times it will drop to like 350 or under before it will catch itself. It is set and trying to idle about 850. This is causing issues when I try to do a crankshaft position sensor relearn as when it drop to about 350 it fails the relearn.

Thanks

Marty

[dhoagland]

Last Ford I worked on (Not Custom Tuning) was a 2012 F150
It needed the Throttle Body relearn performed. I have no idea if this applies here, just a thought, Possibly TB Cleaning? Just some thoughts.

[mlecy]

ok. I will have to see if I can find the option for Throttle body relearn. The throttle body is new. It is a twin 69mm.

[dhoagland]

Not sure if this applies to your model, but this worked for me...
https://www.youtube.com/watch?v=ZNxXM75zJOw

[dhoagland]

ok. I will have to see if I can find the option for Throttle body relearn. The throttle body is new. It is a twin 69mm.

How much bigger is this than stock?
You need to wait for a real Ford guy to jump in here, possibly start a new thread "Calibrate a Twin 69TB"

These tables might need to be rescaled. They have to due with calibrating the "Area of the TB". I imagine for Boat loads of calculations.

[mlecy]

I did something like that video said. I used my autel tablet and went into service and then throttle. I had it clear the Keep Alive Memory. Then let it idle for about 10 minutes. From what the scan tool was showing the actual and desired angel were almost identical so it looks like it is working but still have the same issue. Is there any difference in that doing that vs what he was talking about with take the negative battery cable off and have a jumper between that and the positive cable to drain the system.

[dhoagland]

I did something like that video said. I used my autel tablet and went into service and then throttle. I had it clear the Keep Alive Memory. Then let it idle for about 10 minutes. From what the scan tool was showing the actual and desired angel were almost identical so it looks like it is working but still have the same issue. Is there any difference in that doing that vs what he was talking about with take the negative battery cable off and have a jumper between that and the positive cable to drain the system.

Probably not, but it wont hurt anything to try...

Is it a bigger TB than stock?
If so it will probably need some kind of adjustment for the increased area within the Tune.
The tables I showed are a first best guess, but they might not be scale able. And please don't adjust them until you understand them (and I don't)

[dhoagland]

Also Post up a log of this happening
Logging anything you can to do with idle air flow (desired, actual ,correction, etc...) idle fuel trims, idle spark (desired, actual, correction)

[mlecy]

It is larger then the stock on. It is a twin 69mm from VMP. They said I can use the normal MAF table. Here is the log.

[dhoagland]

It is larger then the stock on. It is a twin 69mm from VMP. They said I can use the normal MAF table. Here is the log.

Thats one heck of a log, LOL... Probably need to cut it back to just what applies to your specific vehicle. (Again I wish I knew Fords I could be a better help, I think I have a book in the garage I'll look for.

That being said
First thing I see is the MAF fault that needs corrected / investigated.
(Could be it just needs to be "Tuned" for the new TB airflow)

Also wonder is there is a common 5V signal or ground common between the IAT, Crank Position, and MAF... They all show faults according to the scanner

[dhoagland]

I found my Ford book
It has a specific procedure for adjusting your Tune for a larger TB.
It also says that larger TB can trigger error codes.

But since you have multiply codes you need to rule out wiring and an actual faulty MAF. Its accuracy is what the procedures revolve around

Post up your Tune file so I can insure the tables in this guide match the tables in your file.

[mlecy]

Here is the tune. That code I have had for a while. It started after I forgot to plug the MAF back in a while back after I was working on the car. I have tried to clear it but it comes right back as it says it is a permanent code. I have thought the MAF sensor was ok as the voltage on it does go up and down so it seems to be reading. Unless I am missing something and you are thinking the sensor is going bad and causing part of my issue.

[dhoagland]

Is this the file you have made adjustments to?
If so do you have a Stock File too?

Are you reading the code with a seperate scanner?
Meaning while its running will the code show active as it did with the HP Log?

Its hard to say, as you mention it does seem to work.
Is this a daily driver? Because the permeant codes SHOULD clear after the MAF has performed good through certain drive cycles and conditions.
Example Has passed performance tests from 3 starts below 80 coolant temperature and coolant temperature had increased past 180 degrees every time. I'm sure we can find that criteria.

But lets back up
I'm assuming this was running good until the TB swap?
Stock Cam? Intake? Exhaust?

This thread below gets real deep, don't let it scare you, just showing that a TB swap probably needs tables adjusted (I know they do on the LS Stuff).
https://forum.hptuners.com/showthrea...n-t-Make-Sense

I have some specific things to log, and error graphs to make that can guide you to calibrating the air/throttle tables. I'm just reading through then very carefully.

[mlecy]

Yes this is the most current file I have been working on. I have attached the base tune. I was reading it with HP Tuner's scanner. Normally I think it said current , permanent. It is not currently a daily as it is not running right. Has not left the garage yet since all the changes. Trying to get it to run and idle ok before trying it on a test drive. I have put a couple tanks of gas through it trying to get this figured out.

It did run ok before I torn it all down to make all of these change. But as you can see below it has had almost everything changed.

3.73 Gears.
Long tube headers
Return Style Fuel system from VMP
2000cc FID injectors
Custom Cams from L&M 550 lift 112 intake and 118 exhaust.
VMP Gen 3R supercharger
VMP twin 69mm throttle body
JLT 123 cold air
10% overdrive pulley
Forged Pistons and rods.
Raise the compress with the new pistons to 10.5
Larger radiator
VPM Heat Exchanger
Block has been bored and sleeved. Bore is now 3.700 which makes it about 5.9L now
ARP studs for everything.
Heads have been ported and different valves
3 inch pulley on the supercharger (should make 12-14 pounds of boost)
Forged aftermarket Crankshaft
Has track pack option on that has trans and rearend cooler

Finally have gotten it to the point that it starts and runs just having a few little issues like the this issue so having issues getting the crankshaft position sensor to relearn. Having a couple other little gremilin issues.

Hopefully that answers all of your questions. If not let me know.

Thanks

[dhoagland]

Oh Wow. Thats going to be a beast..

That explains the airflow adjustments.
I'll look at this from a different perspective.

[mlecy]

Thanks. I am trying to read through that link you sent but having a little trouble following it. Yes it will be well into the 1xxx rwhp. I am starting on 93 with boostane. Once I get all the bugs worked out and get used to it then will switch it to e85 and a smaller pulley to turn it all the way up.

[dhoagland]

Thanks. I am trying to read through that link you sent but having a little trouble following it. Yes it will be well into the 1xxx rwhp. I am starting on 93 with boostane. Once I get all the bugs worked out and get used to it then will switch it to e85 and a smaller pulley to turn it all the way up.

Ya
I would just file that link away, lots good info but I don't think its helpful right now

[dhoagland]

For your injectors did all that data come from FIC?
And are they these?
https://fuelinjectorconnection.com/c...-hi-z-for-ford

[mlecy]

The injectors are from FID (Fuel Injector Development) Here is the data I got from them. But we seemed to have problems with the data so did some adjustments to it.

[dhoagland]

I think you might have a MAF issue.
Look at your log. 4 Throttle snaps and your MAF lbs only really moved as I would expect it to once. I though maybe a delay coming from the channels to the chart.
But if you look at the channels it shows the same. Maybe a scan delay, maybe a lazy MAF, but something to look at.