2002 Mazda Protege DX Automatic, 95k Miles, Stock with 600 watt sound system.
Recently did an Oil/Filter change and serviced the transmission w/ Filter and Fluid. Washed the vehicle today and sprayed down the engine bay. On the way home I was slowing down for a red light which turned green before coming to a stop and at 25mph I went to accelerate and the car stumbled slightly to the point where it seemed like the transmission was searching for the correct gear to down shift to. No issues after that until I got home. The vehicle was in the drive way at idle with the a/c on and it stumbled to the point that it ALMOST stalled and then recovered. I let the vehicle cool off for about 1hr and then went out to take a look at it.
I started with the voltage and used my Midtronics Battery/Alt/Starter Tester. Initially the vehicle stalled after about 10 secs of running when cold. Started it back up and everything ran like normal. Voltage wise everything checked out good. CCA - 820, Battery Voltage 12.86v when vehicle was off, Volts to starter 11.50v, Idle amps prior to accessories 14.4v. But, I noticed with the A/C on Max, stereo was on at listening level while driving, and head lights on, the voltage AT IDLE would drop to 12.53v from a slow bleed off from 13.4v. If I gave it some gas the voltage would rise telling me the alternator is working. I did this test because the Alt is Original.
Once I turned off the A/C the vehicle would then start to stumble and recover repeatedly. Voltage was at 13.46v during the stumbling, then recover.
Curious what this could be? No Check Engine Light.
Parts replaced within the last 30k mile or less...
Spark plugs/Wires - AC Delco
Ignition Coils - Beck Arnley
Fuel pump - Mazda Geniune
Fuel Pressure Regulator - Borg Warner
EGR Valve - Borg Warner - with updates
PCV Valve - AutoZone
Timing Belt/Pulleys/Tensioner - Contenintal( yes like the tire co.)
Water Pump - Mazda Genuine
A/C Compressor - Hitachi
Battery - Optima
At this point I am leaning on either the Coil packs AGAIN, or the speed sensor in the transmission - Possibly
Any pointers would be great
Recently did an Oil/Filter change and serviced the transmission w/ Filter and Fluid. Washed the vehicle today and sprayed down the engine bay. On the way home I was slowing down for a red light which turned green before coming to a stop and at 25mph I went to accelerate and the car stumbled slightly to the point where it seemed like the transmission was searching for the correct gear to down shift to. No issues after that until I got home. The vehicle was in the drive way at idle with the a/c on and it stumbled to the point that it ALMOST stalled and then recovered. I let the vehicle cool off for about 1hr and then went out to take a look at it.
I started with the voltage and used my Midtronics Battery/Alt/Starter Tester. Initially the vehicle stalled after about 10 secs of running when cold. Started it back up and everything ran like normal. Voltage wise everything checked out good. CCA - 820, Battery Voltage 12.86v when vehicle was off, Volts to starter 11.50v, Idle amps prior to accessories 14.4v. But, I noticed with the A/C on Max, stereo was on at listening level while driving, and head lights on, the voltage AT IDLE would drop to 12.53v from a slow bleed off from 13.4v. If I gave it some gas the voltage would rise telling me the alternator is working. I did this test because the Alt is Original.
Once I turned off the A/C the vehicle would then start to stumble and recover repeatedly. Voltage was at 13.46v during the stumbling, then recover.
Curious what this could be? No Check Engine Light.
Parts replaced within the last 30k mile or less...
Spark plugs/Wires - AC Delco
Ignition Coils - Beck Arnley
Fuel pump - Mazda Geniune
Fuel Pressure Regulator - Borg Warner
EGR Valve - Borg Warner - with updates
PCV Valve - AutoZone
Timing Belt/Pulleys/Tensioner - Contenintal( yes like the tire co.)
Water Pump - Mazda Genuine
A/C Compressor - Hitachi
Battery - Optima
At this point I am leaning on either the Coil packs AGAIN, or the speed sensor in the transmission - Possibly
Any pointers would be great