Loss of power on a 97 pontiac sunfire

Possible valve guide seals are leaking motor oil. The motor oil on the spark plugs can cause a misfire and a loss of power.

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The 2.2 or 2200 four cylinder engine is bad for lifter rattle after the mileage gets up there, timing gears are also noisy in them.. I have had good luck using full synthetic oil, I would buy an engine oil flush kit with the next oil change and then use synthetic, If this noise isnt consistant with engine speed, then i would look at pumps and pulleys on the fron of the motor, sometimes AC pump clutches get squeeky and often rattle when disingaged, try turning the AC or defroster on and of to test for a change in the noise.

Timing CHAIN tensioner you mean? Better have that noise checked ASAP. It may be a problem with the timing chain.

could be the timing chain. Was it a pop or more like a ping . A ping could indicate a timing chain problem. The tensioner might have gone bad.
its not hard to replace for an experienced mechanic

sorry to say this, but sounds like the engine might be done, starting to seize up, have someone do an oil sample to see if any metal in the oil

I am having the exact same problem with my 97 sunfire! LOL Help! I heard it might be the coil pack or the fuel pump? I hope not the fuel pump. It got towed today...

The rod knocking is caused by loss of oil pressure. Did the oil light not come on? That light is red, red means stop. Do not start this engine again until the problem is corrected.

Have you checked the oil level?

Check your converter on your exhaust when it's running and see if the noise of rattling is coming from there.If it is you have a plugged converter,it's broken up and in piece's which will make noise and no power especially when calling for power.Be sure to let exhaust cool before repair is done.If the engine is making the noise like a knocking sound you should bring it to have it checked.Hope this help's.

Sure sounds like the engine has a failed bearing, most likely a rod bearing, the engine will need to be pulled out and repaired or replaced depending on how much damage you have done driving it.