BLM 15, INT 128 Engine missing/stumble help
09-11-2017, 11:55 AM
#1
BLM 15, INT 128 Engine missing/stumble help
Typo: BLM 150
Trying my thread here. Posted in the Tech but not too much assistance so far.
1989 LB9 with TH700R4 117,000 miles Stock except for 3:42 gears
What's been done: (Most parts are AC Delco)
Replaced:
Mechanical: Valve Seals and springs, timing set, plenum seals, vacuum lines
Ignition: plugs, wires, cap, rotor, coil, module, pickup
Fuel: injectors (Bosch D3 19 lb), filter, pump, regulator checked OK
ECM: swapped
Electrical: alternator, battery
Sensors: All
Cooling: Thermostat, water pump, radiator, hoses
Emissions: smog pump
Checked:
Fuel System 37-43 psi in all conditions (idle, full throttle). No leakdown, no fuel coming from regulator vacuum port, holds vacuum
Intake: TB cleaned, idle base set
Emissions: secondary air injection check valves and solenoids
Vacuum leaks with carb cleaner spray
Fluids: Oils: All Mobil 1 - Engine and Trans, coolant: GM OEM green
The car should running perfectly and it does sometimes.
The stumble is not always there but once it starts it stays.
Important: It can start to stumble when the engine is first started up (Open Loop). It sometimes doesn't though. After the engine runs for 10-15 mins.
My BLMs stay high.
I plugged off the secondary air injection and every vacuum hose and the BLMs stayed high.
I am not sure what to do here. Looking for help.
Latest data file attached.
Trying my thread here. Posted in the Tech but not too much assistance so far.
1989 LB9 with TH700R4 117,000 miles Stock except for 3:42 gears
What's been done: (Most parts are AC Delco)
Replaced:
Mechanical: Valve Seals and springs, timing set, plenum seals, vacuum lines
Ignition: plugs, wires, cap, rotor, coil, module, pickup
Fuel: injectors (Bosch D3 19 lb), filter, pump, regulator checked OK
ECM: swapped
Electrical: alternator, battery
Sensors: All
Cooling: Thermostat, water pump, radiator, hoses
Emissions: smog pump
Checked:
Fuel System 37-43 psi in all conditions (idle, full throttle). No leakdown, no fuel coming from regulator vacuum port, holds vacuum
Intake: TB cleaned, idle base set
Emissions: secondary air injection check valves and solenoids
Vacuum leaks with carb cleaner spray
Fluids: Oils: All Mobil 1 - Engine and Trans, coolant: GM OEM green
The car should running perfectly and it does sometimes.
The stumble is not always there but once it starts it stays.
Important: It can start to stumble when the engine is first started up (Open Loop). It sometimes doesn't though. After the engine runs for 10-15 mins.
My BLMs stay high.
I plugged off the secondary air injection and every vacuum hose and the BLMs stayed high.
I am not sure what to do here. Looking for help.
Latest data file attached.
Last edited by Tootie Pang; 09-11-2017 at 01:05 PM.
