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Problem: bogging and backfiring (intake) typically 1800 - 2000 RPM. Starts to bog and run rough, backfires, runs better. Generally lacking in power. Scan indicates lots of knock (1800+ in 20 minutes)

Checked or replaced firing order, CTS, TPS, MAP, EGR, distributor/cap/rotor, plugs, timing (0 with EST disconnected), fuel pressure (13), vacuum static (18) and leak tested using propane, O2 sensor, knock sensor, and compression (145-160)

Recent changes that somehow caused the problems: Edelbrock heads/intake, shorty headers, new distributor, CAI, new coil , new fuel pump, 65 lb injectors (OEM 55's same problem)

Running a log using TunerPro indicates that BLM is consistently 107-117 indicating that it thinks the engine is running rich. No CEL and no error codes logged. If it helps, the log is available.

If I disconnect EGR, Less backfire (but still there) and no hesitation off idle.
 

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Problem: bogging and backfiring (intake) typically 1800 - 2000 RPM. Starts to bog and run rough, backfires, runs better. Generally lacking in power. Scan indicates lots of knock (1800+ in 20 minutes)

Checked or replaced firing order, CTS, TPS, MAP, EGR, distributor/cap/rotor, plugs, timing (0 with EST disconnected), fuel pressure (13), vacuum static (18) and leak tested using propane, O2 sensor, knock sensor, and compression (145-160)

Recent changes that somehow caused the problems: Edelbrock heads/intake, shorty headers, new distributor, CAI, new coil , new fuel pump, 65 lb injectors (OEM 55's same problem)

Running a log using TunerPro indicates that BLM is consistently 107-117 indicating that it thinks the engine is running rich. No CEL and no error codes logged. If it helps, the log is available.

If I disconnect EGR, Less backfire (but still there) and no hesitation off idle.


i had the same switched out mass air sensor no problem now
 
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