Year/Make/Model: 2008 Mazdaspeed 3
Mileage: 150,000 on body, ~60,000 on engine
Location: Maryland
Concern: Black/blue smoke out of exhaust when accelerating from idle or after deceleration
DTC's: none
Modifications: CPE Catless DP, Corksport catback, Autotech HPFP, Stock diameter intake, CPE TMIC, 3-port EBCS, Action Clutch steel flywheel, new LUK clutch
ECU/Tuning Software: Cobb
Tuner: PD Tuning
Is the concern intermittent?: No
Can you duplicate the concern?: Yes
Recent Repairs: Swapped engine for used JDM engine, turbo replaced with CW K04 last summer
Hello everyone. I recently replaced my engine with a JDM engine from an importer in Maryland. Compression came back with all cylinders at ~175 - 185 psi, leakdown for all cylinders was less than 5%. The engine is smooth and pulls hard. I changed the engine because the old engine was down on compression and using a lot of oil. The mods I listed above were all on the old engine so the only thing that changed was the engine itself. The issue only presents when the engine is not cold. I am seeing a dark smoke when I give it any gas after idling (even just revving) and if I am decelerating and then accelerating again. I have driven the car about 300 miles since I changed the engine and there is no observable change in coolant or oil level. The cylinders and the spark plugs are dry.
Not sure if this would help but under harder acceleration, there is quite a bit of black smoke that comes out the exhaust which I am assuming is fuel. I would guess that is a separate tuning issue but this also did not happen with the old engine on the same tune.
My guess is valve seals but I know that is very uncommon on this engine. It also does not smoke on cold start. Any help is greatly appreciated!!
Mileage: 150,000 on body, ~60,000 on engine
Location: Maryland
Concern: Black/blue smoke out of exhaust when accelerating from idle or after deceleration
DTC's: none
Modifications: CPE Catless DP, Corksport catback, Autotech HPFP, Stock diameter intake, CPE TMIC, 3-port EBCS, Action Clutch steel flywheel, new LUK clutch
ECU/Tuning Software: Cobb
Tuner: PD Tuning
Is the concern intermittent?: No
Can you duplicate the concern?: Yes
Recent Repairs: Swapped engine for used JDM engine, turbo replaced with CW K04 last summer
Hello everyone. I recently replaced my engine with a JDM engine from an importer in Maryland. Compression came back with all cylinders at ~175 - 185 psi, leakdown for all cylinders was less than 5%. The engine is smooth and pulls hard. I changed the engine because the old engine was down on compression and using a lot of oil. The mods I listed above were all on the old engine so the only thing that changed was the engine itself. The issue only presents when the engine is not cold. I am seeing a dark smoke when I give it any gas after idling (even just revving) and if I am decelerating and then accelerating again. I have driven the car about 300 miles since I changed the engine and there is no observable change in coolant or oil level. The cylinders and the spark plugs are dry.
Not sure if this would help but under harder acceleration, there is quite a bit of black smoke that comes out the exhaust which I am assuming is fuel. I would guess that is a separate tuning issue but this also did not happen with the old engine on the same tune.
My guess is valve seals but I know that is very uncommon on this engine. It also does not smoke on cold start. Any help is greatly appreciated!!
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