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Turbo Tuning / Idle Issues
« on: January 08, 2016, 08:44:53 PM »
Hey guys!
New to the forums, but have been reading through lots of threads and you guys have helped me a lot with my build!
I've spoken on the phone with Brody, and first of all I'd like to say I'm very happy with the m50/s50 turbo tuning kit. The WAR chip software is an amazing platform that has extended my knowledge of cars tenfold. So far on the base tune my car pulls great at 9psi, and I've been successfully playing around with the tune to get the AFRs around 12.5 at WOT. Part throttle the car is settling nicely around 14.7 at cruising speeds.
HOWEVER here's my current issue which is related to this thread ( http://forums.millerperformancecars.com/index.php?topic=65.msg241#msg241 ):
-When I cold start the car, I need to pump the throttle right afterwards because it seems like the car has fuel starvation and wants to stall out. The car will then idle fine and start to warm up, but I notice that my AFR's slowly drop from ~14.7 all the way down to about 10.9, which is way to rich I think.
-Additionally, the idle tends to lean out intermittently and the car stalls once its warm. Doesn't matter if I drove it around or not, I need to feather the gas so that the idle will hold. From what I've been told by the admins at MP and from what I've read, I do think that the O2 sensor is overshooting the fuel corrections to bring the AFRs to 14.7, and that by changing the idle fuel values, I can minimize how much correction is needed to smooth out my idle. The AFRs once the motor is warmed up hovers at about 11. My current issue lies here, because so far I've tried changing the idle fuel values on the base tune from 100 down to 70, but once rewritten I see no change in the AFR's, it even drops a bit down to 10.8 occasionally. Turning the O2 sensor off hasn't made any noticeable affect, but I will continue playing with the fuel map and O2 sensor tab tomorrow to see if I make any progress!
Here is a list of the major components of my build:
0.120" MLS Head Gasket
ARP Head studs kit
Precision 5858 turbo
Miller WAR chip
60 lb siemens injectors
Miller MAF
CXracing intercooler
CXracing tubular T3 manifold
Tial WG and
Tial BOV (Currently open vent at idle, good/bad?)
3" plumbing
IE Oil cooler cap + oil cooler
AEM wideband O2 sensor + gauge
Replaced components:
O2 sensor
Knock sensors
Camshaft + Crankshaft position sensors
fuel pump
copper plugs (gapped to 0.025")
Ignition coils +boots
Cylinder head temp sensors
Oil pressure sensor
Both timing chain tensioners
Addionally:
-ecu scanned with no codes
-O2 sensors are about 5" from the exhaust turbine of the turbo
-cleaned ICV (strong buzz when key is in the ON position)
-inspected for boost leaks (car idles at about 22 mmHg of vacuum pressure)
-inspected FPR
-fuel pressure will be inspected, because I'm not sure how recent my fuel filter was replaced
Are there any other fuel maps I can modify to further diagnose the issue(I.e CT idle fuel maps, acceleration enrichment) and/or anything I should check mechanically? Any advice/suggestions/input would help me a lot! I'm very enthusiastic about finishing my build, and this is the final thing that needs to be resolved to get my car to the dyno! My apologies for the dense post! I appreciate all the help!
Cheers to a new year!
New to the forums, but have been reading through lots of threads and you guys have helped me a lot with my build!
I've spoken on the phone with Brody, and first of all I'd like to say I'm very happy with the m50/s50 turbo tuning kit. The WAR chip software is an amazing platform that has extended my knowledge of cars tenfold. So far on the base tune my car pulls great at 9psi, and I've been successfully playing around with the tune to get the AFRs around 12.5 at WOT. Part throttle the car is settling nicely around 14.7 at cruising speeds.
HOWEVER here's my current issue which is related to this thread ( http://forums.millerperformancecars.com/index.php?topic=65.msg241#msg241 ):
-When I cold start the car, I need to pump the throttle right afterwards because it seems like the car has fuel starvation and wants to stall out. The car will then idle fine and start to warm up, but I notice that my AFR's slowly drop from ~14.7 all the way down to about 10.9, which is way to rich I think.
-Additionally, the idle tends to lean out intermittently and the car stalls once its warm. Doesn't matter if I drove it around or not, I need to feather the gas so that the idle will hold. From what I've been told by the admins at MP and from what I've read, I do think that the O2 sensor is overshooting the fuel corrections to bring the AFRs to 14.7, and that by changing the idle fuel values, I can minimize how much correction is needed to smooth out my idle. The AFRs once the motor is warmed up hovers at about 11. My current issue lies here, because so far I've tried changing the idle fuel values on the base tune from 100 down to 70, but once rewritten I see no change in the AFR's, it even drops a bit down to 10.8 occasionally. Turning the O2 sensor off hasn't made any noticeable affect, but I will continue playing with the fuel map and O2 sensor tab tomorrow to see if I make any progress!
Here is a list of the major components of my build:
0.120" MLS Head Gasket
ARP Head studs kit
Precision 5858 turbo
Miller WAR chip
60 lb siemens injectors
Miller MAF
CXracing intercooler
CXracing tubular T3 manifold
Tial WG and
Tial BOV (Currently open vent at idle, good/bad?)
3" plumbing
IE Oil cooler cap + oil cooler
AEM wideband O2 sensor + gauge
Replaced components:
O2 sensor
Knock sensors
Camshaft + Crankshaft position sensors
fuel pump
copper plugs (gapped to 0.025")
Ignition coils +boots
Cylinder head temp sensors
Oil pressure sensor
Both timing chain tensioners
Addionally:
-ecu scanned with no codes
-O2 sensors are about 5" from the exhaust turbine of the turbo
-cleaned ICV (strong buzz when key is in the ON position)
-inspected for boost leaks (car idles at about 22 mmHg of vacuum pressure)
-inspected FPR
-fuel pressure will be inspected, because I'm not sure how recent my fuel filter was replaced
Are there any other fuel maps I can modify to further diagnose the issue(I.e CT idle fuel maps, acceleration enrichment) and/or anything I should check mechanically? Any advice/suggestions/input would help me a lot! I'm very enthusiastic about finishing my build, and this is the final thing that needs to be resolved to get my car to the dyno! My apologies for the dense post! I appreciate all the help!
Cheers to a new year!