I have an 02 Sonata with 115k miles that I have recently replaced the timing belt, timing assembly, "serpentine" belt (the two belts that run the altenator and power steering pumps), spark plugs, fuel pump and cv joints. I now have a rough idle and when accelerating from a stop the car has a slight rumble and does not want to accelerate until I hit 30 mph, after that it accelerates fine. If I manually shift the car from take off I do not have the hesitation issue it accelerates fine. I also have no power going up hill ( only make about 20-25 mph), this is only when going up hill from a stop or under 20 mph. Any help would be greatful

This post has been edited by reah_emerald: Oct 7 2009, 01:24 AM

Dear reah,

If your Sonata ran fine before the timing belt change, we have to suspect the only thing that changed....the timing. Your intake timing sounds like it is retarded several degrees. You need to static time your engine to check.. Remove the upper timing cover, and rotate the crankshaft pulley by wrench until the timing is aligned at the lower timing mark. Check the upper timing marks. Bet the rear (intake) camshaft is 7-10 degrees (3-4 teeth) off. this is not unusual, as the auto tensioner will move the timing mark as it takes up tension in the belt.

Byron

No power going up hills? I'd be checking to make sure the CAT is not plugged. Do you have a check engine light?

I do not have a check engine light on.

Yeah, if you changed the timing belt, an NOW you have the problem, then suspect the timing is off. Pull off the top cover and verify that the marks all line up.

deleted

This post has been edited by importvic: Nov 3 2009, 12:44 PM

reah_emerald, what ended up being your solution? My 02 Elantra GLS Auto is doing the same thing & I haven't messed with the timing belt 4 it 2 happen. At first the RPMs were erratic & would go real low, so I installed a new MAP sensor, & the car ran great. Then a few weeks went by & it Gradually started to hesitate during acceleration under 2500 RPM but then smooths out. The problem is getting worse & she idles really lumpy. I installed a new PCV but it did not help. A solution would be greatly appreciated. (IMG:style_emoticons/default/smile.gif)

Anyone check their ignition coil?

problem fixed: I was under the impression the plugs & cables were changed during the so called tune-up along with my 58k mi motor install I had done several months back when the original engine took a dump. I was taking a closer look at the cables & they were a little dirty, but what struck me was the flying H symbol on the cables. Now I know the guy that did my motor swap is an Autozone not an OEM kinda guy. So I pulled the plugs & they were fouled with a .065-.068 corroded gap. Far from the recommended .039-.043 gap. The cables were pretty stiff & a little dry rotted. I replaced them with Autozone Duralast cables ($38) which are lifetime replacement. A little longer than stock so I had to rearanged the plugs on the coils. I used a set of NGK G-Power BKR5EGP ($2.99 ea) & she's running great. (IMG:style_emoticons/default/smile.gif)