Nathan Wallace
New Member
Hi guys,
2003 Mitsubishi Lancer CH, with 253xxx on the clock (120xxx on 4G94 engine), F4A42 auto trans.
Ok so here is the skinny, brief as possible:
August 2016 - October 2017 - Random loss of power issues while driving, happened about 6 times total in this period, and only while my wife was driving, never to me.
August 2017 - October 2017 - Different loss of power symptom, engine loaded up, belt squeal and a little smoke out the bonnet. Happened once while I was driving, assumed failing AC compressor.
October 2017 - Engine spun a bearing in cylinder 4 (oil starvation), second hand engine put in by yours truly early Nov 2017.
Everything has been perfect for 1700kms, till yesterday.
Jan 24th 2018 - Slight loss of power cough on family trip to the beach. On way back, power loss issue has become permanent. If you mash the go pedal, revs sits around 2K, and total loss of power, car starts slowing.
Can still drive, but must accelerate slowly and keep power output low. You can still get to 100kph, just takes longer to get there than desired.
Also, when you come off the pedal, power resumes when the revs drop, and you feel a little jerk (sometimes, not all the time) as the power comes back.
Power loss point and power return points are very predictable.
Done so far:
LiquidMoly throttle, intake and engine upper cleaner
Injectors cleaned with FlashLube injector cleaner in fresh 98 octane petrol
Checked spark plugs. They have only done 1700kms, and in great nick
Removed air filter and run
Tried some old coil packs from the last engine, that have new leads
New fuel filter
New fuel pump
I tried disconnecting the O2 sensor in the tunnel near drivers foot (can only find one under the car, pre cat), to make the car go into some sort of limp mode and try to use more fuel, and check if CEL comes on.......no change at all, no CEL at all. Theory is that if the problem gets worse, then fuel pump was not keeping up, or if got better, then O2 sensor was playing up. Now that I have no CEL when O2 sensor is gone, maybe that's the culprit?
What else should I be looking at?
2003 Mitsubishi Lancer CH, with 253xxx on the clock (120xxx on 4G94 engine), F4A42 auto trans.
Ok so here is the skinny, brief as possible:
August 2016 - October 2017 - Random loss of power issues while driving, happened about 6 times total in this period, and only while my wife was driving, never to me.
August 2017 - October 2017 - Different loss of power symptom, engine loaded up, belt squeal and a little smoke out the bonnet. Happened once while I was driving, assumed failing AC compressor.
October 2017 - Engine spun a bearing in cylinder 4 (oil starvation), second hand engine put in by yours truly early Nov 2017.
Everything has been perfect for 1700kms, till yesterday.
Jan 24th 2018 - Slight loss of power cough on family trip to the beach. On way back, power loss issue has become permanent. If you mash the go pedal, revs sits around 2K, and total loss of power, car starts slowing.
Can still drive, but must accelerate slowly and keep power output low. You can still get to 100kph, just takes longer to get there than desired.
Also, when you come off the pedal, power resumes when the revs drop, and you feel a little jerk (sometimes, not all the time) as the power comes back.
Power loss point and power return points are very predictable.
Done so far:
LiquidMoly throttle, intake and engine upper cleaner
Injectors cleaned with FlashLube injector cleaner in fresh 98 octane petrol
Checked spark plugs. They have only done 1700kms, and in great nick
Removed air filter and run
Tried some old coil packs from the last engine, that have new leads
New fuel filter
New fuel pump
I tried disconnecting the O2 sensor in the tunnel near drivers foot (can only find one under the car, pre cat), to make the car go into some sort of limp mode and try to use more fuel, and check if CEL comes on.......no change at all, no CEL at all. Theory is that if the problem gets worse, then fuel pump was not keeping up, or if got better, then O2 sensor was playing up. Now that I have no CEL when O2 sensor is gone, maybe that's the culprit?
What else should I be looking at?
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