Mechanics

ENGINE PROBLEMS

2000 Hyundai Sonata • 4 cylinder FWD Automatic • 129,000 miles

I bought a 4 cylinder Sonata with 120,000 miles. The PO171 code was on when I got the car. New oxygen sensors were put in before I got the car. I changed the fuel filter, ran every kind of fuel injector cleaner through, another code came up - insufficient engine coolant temp. The car has problems climbing hills and seems to have problems shifting on hills. Also, when cold the car stumbles and has a total lack of any power, unless you let up completely on the gas pedal and you have to do this several times. A mechanic suggested I put in a new fuel pump because the old one was weak. I changed the fuel pump (was a cheap one I bought online - may not be a good one). He also suggested changing the t-stat (which I did) and he said the timing was off a bit. I changed both timing belts but didn't install correctly and ran the car with the timing off. I had to correct the timing. I am afraid I may have damaged valves, however that was 2,000 miles ago. Right before I changed the timing belts, a PO300 code came up and camp up again after the timing belts were changed. A mechanic suggested new plugs and wires (which I did). Every time I made these little repairs the car seemed to do a little better, but codes still keep popping up and the car still has problems on hills, accelerating, and shifting. Just recently I pulled up four codes: PO171, PO335, PO300 & PO725. I will also add that I changed the trans. Fluid when I first got the car and used lucas trans fix. I know there is a small trans. Leak at the radiator. I have not checked the EGR. Can you please give me some suggestions?
Avatar
Joelncope
January 31, 2011.




Check out the related content below while we wait for the question to be answered by a professional mechanic.


AD