94 elantra engine troubles

I have a 1994 elantra, 1.8L. The engine has begun shaking at low idle, almost to the point of stalling while it is in gear. also doesnt shift smoothly, revs up to 4k rpms before shifting into next gear. At first, i though it might be the fuel filter. so i replaced that and it appeared that it had been in backwards. the thicker end had been on top but the new one had "in" printed on the opposite end so i figured that the fuel entered the filter at that end. This didnt help the problem. Changed the spark plugs, several of them were white when i pulled them out. When i got the oil changed the mechanic recommended cleaning the fuel injectors. does this sound like something that would fix the problem? anyone had similar problems? are fuel injectors relatively easy to clean yourself? a buddy of mine thought that the compression in one of the cylinders might be low. thanks for the help.

hey, im having the exact same troubles with my elantra. i have changed the injectors,fuel filter, pvc valve,plugs ,wires, etc.. and nothing has fixed this problem. if you find out what it is please let me know
thankyou lisa

well what i have figure out is that one of my cylinders is running a compression of 20 psi when it should be running at 171 psi. This could mean a couple of things from my undersatnding. If im wrong, anyone feel free to correct me. Most likely it means that the ring around the piston is bad and there is gas and oil mixing in the combustion chamber. I have been told the easiest thing to do is buy a new engine or a new car, but if anyone has any other suggestions, let me know. Is it that hard to change the ring on a piston? Thanks for the help.

I have the same problem about that low compression and as easy as it is to put a new engine in it's pretty costly..... and about changing the piston rings you need to diconnect everything and possibly pull the entire engine out take it aprt from top to bottom pull the pistons out and put new rings on to either way it'll be costly but to rebuild would probably be cheaper in the long run plus you'll know that you wouldnt have to change the seals in the near future as you would with a used engine with nothing done to it..... if you get a used engine you'll have to take it appart to put new seals in it anyways so rebuilding would probably be better but thats my opinion check with a hyundai mechanic or something about it really

i think you'll have to pull it all apart i'll check that for you and get back to you on that

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