Crashdot
Probationary Member
- 24
- 1
- Jul 21, 2010
-
Honolulu,
Hawaii
Hi,
I've been dealing with an annoying problem for months, and the latest condition does not throw a CEL so we're not sure what to do. I've read many threads with these symptoms, checked the service manual, and so on, but can't really afford to keep replacing things until the problem is fixed, so I want to ask if anyone knows what could cause these symptoms without triggering the check engine light.
Car: 1999 Mitsubishi Eclipse GSX ~85,000
Mods: BOV, Profec B spec II boost controller at 10psi, boost guage, hard piping, KN open air intake, front and rear strut bars
Here is the history:
01. Started with very brief losses of power off the line or while accelerating moderately ~3000rpm, really just felt like a brief bump or bogging for half a second
02. Replaced Plugs/wires
03. Added Seafoam
04. CEL triggerd immediately after seafoam indicating O2 sensor in closed loop mode
05. Used tank of treated gas, refueled and reset code
06. CELs O2 Sensor, misfire, and shift position (?), reset and just O2 sensor repeated
07. Replaced O2 sensor
08. A day or two later the car started to run with no malfunctions for a few weeks
09. Suddenly started to intermittently misfire and jerk under any acceleration such as trying to drive in a parking lot
10. CEL Misfire detected
11. Managed to get the car to a garage
12. Replaced coil packs
13. Reset CEL
14. Currently, there is intermittent drastic loss of power / jerking under acceleration and Idle dropping and misfiring every minute or so. Car is basically undriveable
16. There is No CEL being triggered
Things that have been done already:
01. Full diagnostic (no result)
02. Boost leak testing
03. Changed plugs and wires
04. Fuel injector cleaner
05. Replaced coil packs
06. Replaced faulty O2 sensor
Next steps:
01. Change fuel filter (was changed not long ago though)
02. Check fuel control valve
03. Change fuel injectors
04. Fuel pump
Basically, what I want to know is what the most likely causes could be, so I know what to replace first, avoiding items that would trigger a CEL. I don't know if there is a way to test some of the remaining potential causes, such as fuel injectors and fuel flow.
Thanks for your consideration
I've been dealing with an annoying problem for months, and the latest condition does not throw a CEL so we're not sure what to do. I've read many threads with these symptoms, checked the service manual, and so on, but can't really afford to keep replacing things until the problem is fixed, so I want to ask if anyone knows what could cause these symptoms without triggering the check engine light.
Car: 1999 Mitsubishi Eclipse GSX ~85,000
Mods: BOV, Profec B spec II boost controller at 10psi, boost guage, hard piping, KN open air intake, front and rear strut bars
Here is the history:
01. Started with very brief losses of power off the line or while accelerating moderately ~3000rpm, really just felt like a brief bump or bogging for half a second
02. Replaced Plugs/wires
03. Added Seafoam
04. CEL triggerd immediately after seafoam indicating O2 sensor in closed loop mode
05. Used tank of treated gas, refueled and reset code
06. CELs O2 Sensor, misfire, and shift position (?), reset and just O2 sensor repeated
07. Replaced O2 sensor
08. A day or two later the car started to run with no malfunctions for a few weeks
09. Suddenly started to intermittently misfire and jerk under any acceleration such as trying to drive in a parking lot
10. CEL Misfire detected
11. Managed to get the car to a garage
12. Replaced coil packs
13. Reset CEL
14. Currently, there is intermittent drastic loss of power / jerking under acceleration and Idle dropping and misfiring every minute or so. Car is basically undriveable
16. There is No CEL being triggered
Things that have been done already:
01. Full diagnostic (no result)
02. Boost leak testing
03. Changed plugs and wires
04. Fuel injector cleaner
05. Replaced coil packs
06. Replaced faulty O2 sensor
Next steps:
01. Change fuel filter (was changed not long ago though)
02. Check fuel control valve
03. Change fuel injectors
04. Fuel pump
Basically, what I want to know is what the most likely causes could be, so I know what to replace first, avoiding items that would trigger a CEL. I don't know if there is a way to test some of the remaining potential causes, such as fuel injectors and fuel flow.
Thanks for your consideration