Stumped the SCT tuner

[jdlatil]

Took my car to JMS Performance today to get custom tune. After four hours of trying we could not get enough fuel added to cover the the 11 pounds of boost car was making. Car would go super lean at 4,000 rpm. They tried to increase fuel by 100% then 200% but the injectors were not responding or the PCM was not telling injectors to add more fuel.
We checked both fuel pumps (AEM's) both running, disconnect fuel line to gas can had plenty of volume.
Fuel pressure at regulator good and raising to 60 pounds on boost, good at fuel rail up to 60 pounds.
Checked coils, checked compression.

Strange thing was when we pulled the FPS plug on fuel rail the fuel pressure registered 39 lbs, it should spike up to 80 pound when disconnected. Stayed steady at 39. Can not understand why.

After alot of different adjustment on the SCT tuner, we swapped out the PCM with a car that had extract same number, still could not be the car to do any thing but go lean.
Had to take car home with out being tuned.

I guess I will be doing alot back tracking, checking wiring harness, and data logging to find out why.

Runs good if you don't get into boost.

Possible 800 horsepower car with 300 hp!!!!

Suggestions?

This is a build 3V in my 2007 Mustang GT with a Stealth Single Turbo from S&H 70 MM .
1000 horsepower fuel system Division X from Leathal Perfomance.

 

[stkjock]

Are you sure the injectors are big enough and that JMS was using the correct calibration for the brand and size?

 

[BruceH]

Do you know what the maf voltage was? I'm sure they logged to see if it was pegged.

 

[lskiller]

The MAF/Injector data could be hosed. If it's fine down low with decent fuel trims but going way lean up top you may have a high slope data issue. Just something to check. Also, the Fuel Rail Pressure Sensors DO fail on occasion and that would cause fuel pressure not to rise with boost leading to a lean condition.

If the PCM isn't commanding more fuel when you expect it to it's got bad data in the tune or is getting a bad input somewhere.

Good luck with it - hope it sorts out soon!

 

[lskiller]

Something I learned the hard way... use a dedicated vacuum/boost source for the FRPS if at all possible.

 

[lito]

Whose JMS is this?

 

[jdlatil]

ID 1000 plenty enough.
I'm sure they done them before.

 

[jdlatil]

JMS Chip Performance

 

[lito]

Sincerely think it may be a tune issue.

 

[jdlatil]

MAF was responding fine with Roma.
Not pegged.

 

[jdlatil]

Only using the Ford pump system to run relays to run twin in tank pumps and have regulator return style fuel system.

 

[lskiller]

Did you get this figured out?

 

[jdlatil]

No not yea, going to check FPS wiring to PCM, double check fuel system, clean Mass air and start doing some data logging.
I'm not too experienced with possible issues like this.

 

[weather man]

No not yea, going to check FPS wiring to PCM, double check fuel system, clean Mass air and start doing some data logging.
I'm not too experienced with possible issues like this.

Get an outside expert opinion, talk to LITO, cheap investment.

 

[jdlatil]

Sorry for not reporting great news earlier.
Got in touch with Manuel (LITO) at [email protected]
This man is definitely an expert! We agreed to let him tune my car.
From the very first tune me sent to me the car started, idled, drove with out issue and the fuel lean issue correct! Manuel guided me and taught me a lot about tuning, being new to the turbo game.
Manuel has currently got the car running monster strong up to 16 lbs boost. The car is scary fast, when that boost kicks in the car screams all the way to 6,800 rpm and never fades.
If any one needs a great tuner don't hesitate their is only one name to remember.
LITO !

This old man has name him the "Tune Master"
Thanks Manuel for your expertise and patience!

 

[LAStang1234]

Sorry for not reporting great news earlier.
Got in touch with Manuel (LITO) at [email protected]
This man is definitely an expert! We agreed to let him tune my car.
From the very first tune me sent to me the car started, idled, drove with out issue and the fuel lean issue correct! Manuel guided me and taught me a lot about tuning, being new to the turbo game.
Manuel has currently got the car running monster strong up to 16 lbs boost. The car is scary fast, when that boost kicks in the car screams all the way to 6,800 rpm and never fades.
If any one needs a great tuner don't hesitate their is only one name to remember.
LITO !

This old man has name him the "Tune Master"
Thanks Manuel for your expertise and patience!

Glad you went with Lito!! He tuned my ProCharger as well, absolute awesome guy all the way around.

When's track time? Lol

 

[BruceH]

Sorry for not reporting great news earlier.
Got in touch with Manuel (LITO) at [email protected]
This man is definitely an expert! We agreed to let him tune my car.
From the very first tune me sent to me the car started, idled, drove with out issue and the fuel lean issue correct! Manuel guided me and taught me a lot about tuning, being new to the turbo game.
Manuel has currently got the car running monster strong up to 16 lbs boost. The car is scary fast, when that boost kicks in the car screams all the way to 6,800 rpm and never fades.
If any one needs a great tuner don't hesitate their is only one name to remember.
LITO !

This old man has name him the "Tune Master"
Thanks Manuel for your expertise and patience!

Good to hear. He is the wizard when it comes to tuning. His knowledge of internal combustion engine theory and electronic engine management make him the go to guy for just about anything Mustang related.

This means that not only does he know how to tune but he knows why changing parameters changes how the motor runs.

 

[JeremyH]

Sorry for not reporting great news earlier.
Got in touch with Manuel (LITO) at [email protected]
This man is definitely an expert! We agreed to let him tune my car.
From the very first tune me sent to me the car started, idled, drove with out issue and the fuel lean issue correct! Manuel guided me and taught me a lot about tuning, being new to the turbo game.
Manuel has currently got the car running monster strong up to 16 lbs boost. The car is scary fast, when that boost kicks in the car screams all the way to 6,800 rpm and never fades.
If any one needs a great tuner don't hesitate their is only one name to remember.
LITO !

This old man has name him the "Tune Master"
Thanks Manuel for your expertise and patience!

Great news Jack!

 

[Wes06]

Props for Lito
I've loved his tune since my first full WOT pull

 

[lito]

Sorry for not reporting great news earlier.
Got in touch with Manuel (LITO) at [email protected]
This man is definitely an expert! We agreed to let him tune my car.
From the very first tune me sent to me the car started, idled, drove with out issue and the fuel lean issue correct! Manuel guided me and taught me a lot about tuning, being new to the turbo game.
Manuel has currently got the car running monster strong up to 16 lbs boost. The car is scary fast, when that boost kicks in the car screams all the way to 6,800 rpm and never fades.
If any one needs a great tuner don't hesitate their is only one name to remember.
LITO !

This old man has name him the "Tune Master"
Thanks Manuel for your expertise and patience!

Thanks Jack! It was a pleasure working with you.

Lito 1 - JMS 0 ;-)