Power Loss/Inconsistent Revving (Possible Misfire)
Hey guys, I really need some assistance here. So I just got gifted a 97 Honda Civic EX 4 cyl. It was running great but had plans to drive this long distance and wanted to do some much needed maintenance - oil change/filter, replaced spark plugs, spark plug wires, replaced air filter, etc.
Now that all thats done the car is having issues. I have done spark plugs and oil changes several times and know what Im doing. I gapped the plugs to 0.044 (as its suppose to be), used thread sealer, and inserted them hang tight. Went back and checked that the gapping was accurate for all of them and it was. Oil filter is on tight and oil levels look good as i checked several times.
Heres whats happening - while driving it feels like its misfiring, even going slow speeds and more so noticable at high speeds, it revs up really, really high then struggles to shift gears it feels (this is an automatic), and it will go all the way up to 3.5 to 4 rpms then shifts after sitting on that. While trying to go on the freeway, it takes a long time to get to 60 mph and once I do it sits at or around 3 - 3.5 rpms...which is too high. It used to sit at 2.5 which is normal and feels normal. Now I can feel it straining the engine and it I can hear it struggling because its humming loud from being at the higher RPMs. Then Ill have to push the pedal all the way to floor in hopes to gain speed and get it into the next gear and it will struggle and just sit at that speed. Trying to go uphill is the worst. I cant tell if this a misfire or lack of power from the intake or both. But I tested the air filter. Got rid of the old, replaced it with a newer one, and put it in a place where it could get better air access and no difference. It also will rev and rpms will bounce and go up as Im braking making me sputter to stops. The other big issue I keep seeing is I put coolant in the radiator and then some in the resevoir. Then it will overflow. So I drained it out of the resevoir, and just left what was in the radiator, and woke up the next day to find it bone dry. Then I did that same thing except I only put coolant in the radiator, and the same thing happened. All of a sudden its overflowing in the resevoir, and I have no idea whats going on.
This is so frustrating because everything was great with the car before, except no maintenance had been done for several years. Oil was black, spark plugs were toast, and the air filter was built with a dryer vent tube, duct tape and a massive truck air filter that was crammed in there.
Please help! I feel like Im harming my engine by driving this and I want to know what to do to fix this.