apachechef
Burnt Sierra Madre
- Joined
- Jan 26, 2009
- Location
- An obscure body in the SK system
1993 240 LH2.4
Running great, begins to run roughly on highway(weak power,revving it smooth it, but rattle sound perhaps valvular origin?? when under load ,),pull over engine shakes hard back (4inches) and forth at idle, smooths out mostly with opening throttle. and revving it up.
pulling spark leads to cyl 1 and 2 does nothing, pull 3 or 4, engine dies.
changing plugs, plug wires, checking spark, seems 1 and 2 are sparking away just fine.
noid light on injector 1 and 2 flashes normally while engine is "running", engine won't start with the noid in 3 or 4, but flashes when cranking.
pulling leads off 1 or 2 does nothing, but 3 or 4 kills the engine.
pull rail, place injectors in bottles, connect the two ground wires back onto manifold.
crank the engine, get a little fuel in each bottle, and all 4 have equal amounts.
So, I'm thinking I have spark in 1 and 2, and fuel in 1 and 2, but removing spark plug leads or injector leads does not change rough idle
engine runs relatively smoother with opening the throttle and revving it up under no load, but IIRC loading it caused a valve like rattle and almost no power.
No obvious smoke from exhaust.
Diagnosis?
1 and 2 are not making power, despite fuel and spark, and the apparent "smoothening" with revving while parked could just be from 3+4 and enough speed being enough to not shake like at idle. that leaves valvetrain or compression?
tomorrow: compression test and borescopy?
Confused as to what would take out cyl 1 and 2.
Thanks
Running great, begins to run roughly on highway(weak power,revving it smooth it, but rattle sound perhaps valvular origin?? when under load ,),pull over engine shakes hard back (4inches) and forth at idle, smooths out mostly with opening throttle. and revving it up.
pulling spark leads to cyl 1 and 2 does nothing, pull 3 or 4, engine dies.
changing plugs, plug wires, checking spark, seems 1 and 2 are sparking away just fine.
noid light on injector 1 and 2 flashes normally while engine is "running", engine won't start with the noid in 3 or 4, but flashes when cranking.
pulling leads off 1 or 2 does nothing, but 3 or 4 kills the engine.
pull rail, place injectors in bottles, connect the two ground wires back onto manifold.
crank the engine, get a little fuel in each bottle, and all 4 have equal amounts.
So, I'm thinking I have spark in 1 and 2, and fuel in 1 and 2, but removing spark plug leads or injector leads does not change rough idle
engine runs relatively smoother with opening the throttle and revving it up under no load, but IIRC loading it caused a valve like rattle and almost no power.
No obvious smoke from exhaust.
Diagnosis?
1 and 2 are not making power, despite fuel and spark, and the apparent "smoothening" with revving while parked could just be from 3+4 and enough speed being enough to not shake like at idle. that leaves valvetrain or compression?
tomorrow: compression test and borescopy?
Confused as to what would take out cyl 1 and 2.
Thanks