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1990 legacy 360k 2.2 5 speed, clutch replace 120k ago.

 

I noticed that I have to shift up a lot sooner or else the car bogs down (lose of power). Those of you that own a manual probably know what i am talking about, you get the hard chug chug which tells you to shift up. This happens in 2-5 gears. Could it be the clutch or am I having a fuel sending problem. I hope this makes sense

Brian

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I suppose the chug-chug-chug you describe could be a slipping clutch.

 

Does the tach skip around when this happens? In other words, does the engine seem to be racing when these symptoms appear?

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I suppose the chug-chug-chug you describe could be a slipping clutch.

 

Does the tach skip around when this happens? In other words, does the engine seem to be racing when these symptoms appear?

 

no, if that was happening I would know it was the clutch

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Compression is probably fine. Fine for an engine with 360k anyway.

 

Plugged cat you typically get a rotten egg smell. Engine doesn't make power at higher rpms or under heavy load because of excessive back pressure in the exhaust. It's unable to push out the exhaust fast enough to make room for fresh air/fuel to come in so power drops. The cat may also get very hot, and in some cases glow red / orange.

There are a few tests that can be done to check for a plugged cat. A vacuum gauge attached to the engine will tell you if vacuum is dropping when the power loss occurs, which can be an indicator.

Testing the back pressure of the exhaust is the best way but can be difficult without the right tools.

You can also remove the cats and inspect them visually for obstruction.

Do you have emissions testing in your area? A shop that does emissions generally will have the equipment to do a diagnostic on the cats without removing them.

If you don't have emissions testing, you can gut them for a temporary solution, though in the end you probably should "replace" them. :brow:

 

Other causes, as said before, clogged fuel and/or air filters. Power loss can also be caused by a dirty MAF sensor, bad knock sensor, bad throttle position sensor, low fuel pressure, jumped timing. The PCV valve can cause running issues if it gets clogged/ gummed up. Loose intake hoses, cracked or loose breather hoses (from the valve covers to the intake tube). Lots of things can cause power issues. Start with the simple stuff, give everything a good checking over and do some general tune-up stuff if it hasn't been done in a while. Plugs, wires, filters. Any filter more than a year old just needs to be changed anyway whether it helps or not.

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The boot creates a seal around the plug well in the head. Put some silicone grease around the top lip of the boot where it fits into the head. That'll let it slip into the hole easier.

 

Is there any way to describe that without it sounding dirty? :-p

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got all of the plugs to stay in, still running like crapola. I hate to start throwing parts at it and seeing what sticks. i did pull a couple codes off but I don't know how old they are...temp sensor, knock sensor, mass air...however, it has overheated in the past and I did have the mass air flow disconnected one time so I would expect those codes to be on...maybe need to replace knock sensor and plug wires. It really is a strange problem cause sometimes it will run just fine but then mash the pedal and...sputter sputter...any help is appreciated as always.

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Coolant temp. sensor is also easy to replace. Does it stumble only after the engine has reached operating temp.? If so, the car may be running in open loop and, thus, running too rich. Do you smell unburned gasoline from the exhaust?

 

If you're having power issues at higher rpm as alluded to in your original post, then it may very well be a defective knock sensor, as suggested by Fairtax, that is causing the engine to run in safe mode in order to forestall serious engine damage.

 

Either way, both parts are relatively inexpensive and easy to replace.

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