Engine Hesitation - Hyundai Performance Forums

\'01tiburondriver · 04-08-2007, 11:23 PM

so my car is hesitating in 4th and 5th gears, it feels like it hesitates then kicks in and all it's power is there and then kind of dies off again, but it doesn't do it consistantly or predictably! It does happen alot more though going up and DOWN hill. I used some fuel injector cleaner and some fuel system cleaner back to back with results but still same situation just not as often... any ideas anyone?

Killco · 04-09-2007, 12:05 AM

I have a similar issue with the top of my 3rd. I keep thinking it's running too rich. What kind of mods are you running?

wilburisthecoolest · 04-09-2007, 12:10 AM

change your plugs?

Killco · 04-09-2007, 12:19 AM

I alwasy suggest a plug change as well, but if he is experiencing what I am, plugs were not the culprit. Take a plug or two out and tell us what they look like, then we can go from there. Black and sooty - too rich. Melted, cracked, or very glossy brown - too lean (or just really warn out). How many miles do you have and when have you changed the plugs?

wilburisthecoolest · 04-09-2007, 12:23 AM

mine hesitated everytime i hit high rpm, i had bad plugs.. just old, and a clogged fuel filter.

Killco · 04-09-2007, 12:26 AM

Huh, you know what. My fuel filter may need replaced. Sometimes I smell gas when I really get on it after awhile. If the filter under the rear seat?

Killco · 04-09-2007, 12:33 AM

I don't know why I didn't think of that. I just figured I could smell gas a little since I don't have a cat and and it was running rich.

\'01tiburondriver · 04-09-2007, 07:25 PM

ya know i think that's a good idea (the plugs) i have iridium plugs w/ 10mm wires but those were about 30000 - 40000 miles ago, i thought of that just was hesitant to admit it. i'll check it out...

\'01tiburondriver · 04-13-2007, 08:34 PM

so i changed the plugs and the problem ultimately got worst, i thought about one thing though, i have headers that go into a stock exhuast, havent been able to afford the rest yet, and when i did that of course the cel came on for o2 sensor b/c i took out a cat, now is it possible my ecu is going kind of whacky and giving the engine too much fuel? or to little? beacuse of the loss of the o2 sensor reading?

Killco · 04-14-2007, 12:53 PM

That sounds very possible to me. Do you have the sensor hooked up at all? Maybe I misunderstood.