Volvo RWD 200 Forum

Hmmm... quite a description there.

I think a clogged injector is low on the list of culprits, although a poor spray pattern is certainly possible given the age + miles. Techron is the good stuff to use. To do a binary check (it works or it doesn't) of the injectors, hold a long screwdriver to each injector in turn and put the handle up to your ear as the engine idles. You should be able to hear the injector pulsing.

You probably won't get the noise you describe anywhere on the *intake* side... those would probably be a sucking or hissing sound. I'd be inclined to look and listen around the exhaust manifold and downpipe. Carefully feel around the exhaust manifold to see if there's a "freeze" from a leak, but watch out - you can get a nasty burn.

That said, and exhaust leak generally won't result in sluggish performance. A restricted exhaust *will.* I would get under the car and look for a seriously deformed piece in the exhaust system, like around the axle pipe (which is already obscenely flattened when it's bent during fabrication).

Rarely, a cracked downpipe (near the 2 into 1) ends up confounding the oxygen sensor resulting in an ultra-rich mixture, but that doesn't align with your symptoms.

I wouldn't worry too much about valve clearances right now unless you're bored. You might get a little more noise from a loose valve, but that's about it. Valves would have to be pretty far out of spec to affect performance.

If you have a compression tester, use it, and that will give you a good idea of the valves' condition. But you need to pop the valve cover to see 'em and work on 'em.

I recently did my injector seals ('92, 230K) and the old ones had taken a set and were hard but not brittle, but I don't think they leaked. I just had the seals and hand and some extra time one night.

If your t-belt is *really* tired, it's possible that valve timing is off a few degrees. That will get squared away when you do the t-belt.

Last suggestion - check the O2 sensor output with a DMM. A failing sensor won't have the correct output range, and your air/fuel mixture will be off as a result, adversely affecting performance.

Just a few things to look into!

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In God We Trust. Everyone else, keep your hands where I can see them.