Guess what's wrong with my car contest.

My car is in the shop, and hopefully I will know what is wrong with it by Thursday morning. The first person to correctly diagnose the issue wins the title of "Message Board Master Mechanic" and that might come with a trophy and a t-shirt, but probably not.

OK, so I drive a 2008 Kia Rondo with the 2.7L V6. (yes, I know I am a stud) and it has run perfectly for a long time. It ran fine on the way to work, but after sitting for 8 hours, it suddenly was not running so well.

It was sluggish, trying to stall at stop signs, chugging upon acceleration, and the check engine light started to blink, and then came on steady. Oil was good. Trans fluid was good. No obvious blockage to the air intake or filter. No obvious loose plug wires. The only thing that was different (and I hesitate to even mention this) is that my wife stopped by my office and swapped me cars, so I was not the one to start it initially. (She knows how to start a car, I am certain that she was not a factor) It would smooth out once it got over 10 or 15 mph, but would hesitate and chug as soon as you let off the gas.

Bad IAT sensor.

Hit me!

Bad IACV.

what codes is it popping out?

Bobzilla wrote: what codes is it popping out?

No cheating!

EGR valve is stuck open.

I would normally go with IAT or IAC, but Ben already tried that. I'll assume crazy high miles and say fuel filter or the catalytic converter.

Sticking torque converter clutch solenoid?

Can you describe the noise its making?

it's not a Miata, that's whats wrong with it.

tuna55 wrote: I would normally go with IAT or IAC, but Ben already tried that. I'll assume crazy high miles and say fuel filter or the catalytic converter.

Whaaaa??? SOMEONE has a little INSIDE information!

PCV/02 sensor?

Ams/afm short/disconnect/failure

N Sperlo wrote:

tuna55 wrote: I would normally go with IAT or IAC, but Ben already tried that. I'll assume crazy high miles and say fuel filter or the catalytic converter.

Whaaaa??? SOMEONE has a little INSIDE information!

No no, no inside info, you and Ben both suggested that above my post.

Coil is failing.

But I'll go out on a limb that the catalyst is now showing a code, too- going from a blinking light (a sign of misfire) to a solid one.

Streetwiseguy wrote: EGR valve is stuck open.

No EGR valves on the Alpha, Beta, Delta engines.

How long since the t-belt? Stretched and jumped time? Wires? Intake mani-leak (plenum to base gasket is common)? Melted cat? Crank sensor?

First thing I learned in pliers school was the KISS principle. I'm going to say bad gas or partially plugged fuel or air filter.

In reply to tuna55:

Oh. LOL. I don't know that "Ben" was Ben.

Flashing MIL means catalyst harming event occuring..... So it could be as simple as a multiple cylinder misfire or engine timing changed. I just want to ask, when the rough running happens, is it soft or hard? That will tell me the answer.

50,000 miles with regular maintenance and oil changes. No timing belt done yet. Driven as if someone is chasing me most of the time.

The muffler bearing is shot.

02 sensor, vacuum leaks, plug wires. Oh so many possibilities. Add coolant temperure sensor .

I'd go with fuel delivery, or lack of.

Condensation in the gas.

I'll go with sensor issue - afm, maybe tps