Hello everybody,
I have a tuning issue at idle after engine re-build either it will go either rich or lean. It will not be stable at all. see below mods with the situation issue.
Mustang 2v modifications:
D.S.S Racing Block oversize 0.040 with 5.0 Stroker kit, Patriot Stage 2 heads, blower HP292 cams, Paxton Novi 2K with 3.5” blower pulley and 10% Innovate Crank pulley (boost at 14-15), SCT BA2600 MAF, LT headers with full exhaust system, Typhoon Intake manifold, Performance products plenum and 75mm Throttle body, 60lb Siemens Deka Injectors, return-less fuel system with Division X Stryker 340lph single pump, Kenne Bell BAP, and NGK TR6 spark plugs gapped at 0.030.
The car was tuned perfect by all mods mentioned above with same boost except the (DSS Block with 5.0 stroker and Patriot stage 2 heads only).
After the re-build I loaded the new custom tune with changing only Engine Displacement for the new cubic inch to see how the idle will be and correct the tune from there.
1st fire-up the car idle rough and A/F ratio was reading rich 12 and then after 5 mins it goes lean 16-17, then a check engine light came up with code 0602 Control Module programing error. I disabled the code 0602 from SCT Advantage software and switched off the Adaptive control and Cats Temp switches to tune the MAF by STFT1 and 2. I load the tune and the car idle way better and sounds different but the AF ratio still reading lean and goes to 18-19 while the STFT1 and 2 within the specs between 0.95-1.05. I tried to raise the MAF airflow for idle within 20% and the car still will read lean but the STFT1&2 goes to 1.1-1.2 which is adding fuel and then I decrease the MAF airflow by 30% and the car this time will read rich 11-12 AF and the STFT1&2 will go 0.78-0.89.
So, next step I tried to force it to Open loop to tune it by the AF ratio and MAF counts or MAF volt and this time the car idle at AF 11.9-12.8 so I decrease the airflow by 20% and then the car idle lean 16.3-19, I raised the Airflow by 10% and its idling at 12.8-13.4 for 3 mins and then it will go lean 15-16. So, it drives me crazy!!
I don’t know if it is a vacuum leak issue that causing the idle not reading stable or what exactly? Please your support appreciated. I am thinking to do a leak down test to see if I have a leak or not.
Your usual supports really appreciated.
I have a tuning issue at idle after engine re-build either it will go either rich or lean. It will not be stable at all. see below mods with the situation issue.
Mustang 2v modifications:
D.S.S Racing Block oversize 0.040 with 5.0 Stroker kit, Patriot Stage 2 heads, blower HP292 cams, Paxton Novi 2K with 3.5” blower pulley and 10% Innovate Crank pulley (boost at 14-15), SCT BA2600 MAF, LT headers with full exhaust system, Typhoon Intake manifold, Performance products plenum and 75mm Throttle body, 60lb Siemens Deka Injectors, return-less fuel system with Division X Stryker 340lph single pump, Kenne Bell BAP, and NGK TR6 spark plugs gapped at 0.030.
The car was tuned perfect by all mods mentioned above with same boost except the (DSS Block with 5.0 stroker and Patriot stage 2 heads only).
After the re-build I loaded the new custom tune with changing only Engine Displacement for the new cubic inch to see how the idle will be and correct the tune from there.
1st fire-up the car idle rough and A/F ratio was reading rich 12 and then after 5 mins it goes lean 16-17, then a check engine light came up with code 0602 Control Module programing error. I disabled the code 0602 from SCT Advantage software and switched off the Adaptive control and Cats Temp switches to tune the MAF by STFT1 and 2. I load the tune and the car idle way better and sounds different but the AF ratio still reading lean and goes to 18-19 while the STFT1 and 2 within the specs between 0.95-1.05. I tried to raise the MAF airflow for idle within 20% and the car still will read lean but the STFT1&2 goes to 1.1-1.2 which is adding fuel and then I decrease the MAF airflow by 30% and the car this time will read rich 11-12 AF and the STFT1&2 will go 0.78-0.89.
So, next step I tried to force it to Open loop to tune it by the AF ratio and MAF counts or MAF volt and this time the car idle at AF 11.9-12.8 so I decrease the airflow by 20% and then the car idle lean 16.3-19, I raised the Airflow by 10% and its idling at 12.8-13.4 for 3 mins and then it will go lean 15-16. So, it drives me crazy!!
I don’t know if it is a vacuum leak issue that causing the idle not reading stable or what exactly? Please your support appreciated. I am thinking to do a leak down test to see if I have a leak or not.
Your usual supports really appreciated.
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