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Hi everyone - I've got an 86 Volvo 240 Automatic (LH 2.2) that I just can't sort out.
I think it's a fuel/air mixture issue.
A few months ago I took it it out and it died a block away - just bogged down and I barely made it home.
I've done a number of things to it in the last few months with moderate improvement.
Now it will start if I give it gas, but struggles to stay at a high enough and consistent idle. If I put it in gear when still cold it will die. UNLESS I let it warm up for a while, and after about 15/20 minutes the idle will get more consistent and I can drive around. It still seems sluggish though, even then. Occasional backfires, some white smoke at first.
Here's everything I've done, some for good measure, some by good science and Bentley logic:
- replaced the fuel filter (the car sat for long periods a few years ago, and I wondered if maybe some rust got in there)
- verified that both pumps are running (haven't yet measured output though)
- checked for leaky air hoses, replaced "accordion" air intake hose
- new fuel relay
- tested the injection computer and all connections to ensure functionality, continuity (even tried a difft computer for good measure)
- tested the AMM and found it just under par. replaced it.
- compression tests OK
- replaced leaky brake booster check valve
- replaced fuel pressure regulator
- cleaned the throttle body
- checked for exposed wire, taped up some
- verified functionality in the O2 sensor
- verified functionality in the coolant temperature sensor (replaced it anyway for good measure)
- replaced distributor cap and rotor
- plugs and wires are fairly new
- checked all the fuses (including the main fuse)
Setting the idle speed and mix has been difficult. It just doesn't want to idle high enough no matter what I do - I've had to turn the throttle switch pretty far to get the idle where it needs to be. And when I test the mix, I can't get the LED to light up at all. (So that means it's running too rich, right?) It's lit up before this season, so I know I'm hooking it up right.
It seems to me that the only thing left is to replace the injectors, but that's a lot of dough and I don't want to do it if I don't need to. When I do the "unplug the wire" test for each injector I can hear a change in the engine, so I know they're all working, but the car has sat for long periods in its life, and hasn't had a long trip in some time. So maybe they're clogged?
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