Kia Forum banner
1 - 11 of 11 Posts

·
Registered
2006.5 Kia Optima 2.4l 4cyl
Joined
·
9 Posts
Discussion Starter · #1 ·
Hey all. This car has been killing me lately and I'm at a loss with it. Sorry if I throw too much unrelated info at you, just trying to be thorough.

My 2006.5 Kia Optima with ~220k miles started stalling while driving a little over a month ago, immediately after filling the tank up (I had run it VERY low and learned my lesson). Assuming that I had just gotten bad gas, I threw a can of seafoam in it, replaced the gas cap as I had been meaning to anyways, and carried on. After a little driving it seemingly straightened itself out. The next 2 times I filled up the car would start stalling for a short while afterwards but would seem to resolve itself after a bit of driving.
At this point it would stall while cruising mostly and occasionally starting from a stop, but would always turn over without trouble and would idle without any issues. It never once threw a CEL.
I started looking for posts about evap system issues and came across a few posts saying that a new crankshaft position sensor fixed their issues with intermittent stalling w/o a CEL as well as hesitation when accelerating from a stop (I've always had this problem and assumed it was just standard CVT stuff). I cross referenced the manufacturer part number and ordered a replacement from RockAuto (Holstein 2CRK0146), installed it, and the car ran GREAT just long enough for me to think the issue was put to bed (about 140 miles) before it started stalling again, this time when starting from a stop and at idle. If I could get it rolling it ran fine. When I got it home and lo', it had thrown a CEL. P0335: Crankshaft Position Sensor malfunction.
At this point it was stalling at idle. If I unplugged the crank sensor it ran much rougher though, so I decided to take it to a shop and let them sort it out.
It has been at a shop for diagnostics about 3 weeks and they seem to be at a loss. They changed the crank and cam position sensor and said that it was still stalling and throwing the CEL.

To sumarise:
It was stalling while driving w/o CEL: Added seafoam>changed gas cap>changed crank position sensor (checked spark plugs, ohmed coil packs, replaced air filter, cleaned MAF sensor and throttle body)
It is now stalling at idle w/ code p0335: Shop has changed crank sensor again and cam sensor to no avail

I normally work on my own vehicles but am not great with troubleshooting, but it sounds like the shop is just throwing parts at it anyways so I guess it may be time for me to learn. I guess I'm out in the weeds here and just looking for some input/direction.
 

·
Registered
09 kia spectra ex,'11 Dodge Journey AWD,04 Chry. T&C, 08 Pontiac G6 gt
Joined
·
2,512 Posts
OK, so you replaced the CKPS and still getting code..Time to check voltage of the sensor wiring.
Gas cap has nothing to do with driveability after fueling up, more likely something with the canister purge valve.
How faithful have you been on oil change intervals? A VVT engine has oil control solenoids that can gunk up and cause timing issues.
 

·
Registered
2006.5 Kia Optima 2.4l 4cyl
Joined
·
9 Posts
Discussion Starter · #3 ·
What's throwing me off with the sensor is that I wasn't getting the code until 100+ miles after installing the new one. Should I be checking the voltage on the sensor connector or the connector on wiring harness? And what values should I expect to see?

I haven't been great on oil changes but not particularly bad either. I use synthetic and shoot for 5k between changes, I've let it go to about 7k a few times.
 

·
Registered
09 kia spectra ex,'11 Dodge Journey AWD,04 Chry. T&C, 08 Pontiac G6 gt
Joined
·
2,512 Posts
From info you have already posted, there is no way for us to know for sure what codes posted are current or stored history codes. OCV solenoids usually will throw a code when they have a fault, but if only short term will clear and history memory will store the code fault for them. It takes more than just a regular OBD11 scanner to get to history code memory of the computer. Engine oil sludge is a big problem with a lot of VVT timing systems, and one would not know having this condition without pulling off the valve cover to see it or removing the OCV solenoids to inspect them for such. .
Also a big problem with changing out parts without proper diagnostics to prove such part good or bad gets expensive and a "new" part installed again may be faulty right out of the packaging. Most all Kia engine management systems are basically the same between models in how to test sensors and wiring between them and the computer. I'm not good at posting "links" and don't want to write a book on theory and how to test here. I hope you understand my view on the matter.
BUT 3 weeks at a shop and can't figure it out?...get it to a shop that knows how to diagnose KIA/Hyundai vehicles, the current one is doing you no good service.
 
  • Like
Reactions: Schmitty_Man

·
Registered
2006.5 Kia Optima 2.4l 4cyl
Joined
·
9 Posts
Discussion Starter · #5 ·
I changed the valve cover gasket about 50k miles ago and there was virtually no sludge so hopefully that's a good sign on that front.
I've been using a bluetooth OBD2 scanner with torque pro to check codes. I know it shows pending codes but I'm unsure about stored codes.
Do you think it's likely that both the aftermarket CKPS sensor that I installed and that the shop replaced it with were faulty? I'm inclined to assume my problem is somewhere else in the system at this point.

Regardless, you're right about the shop I've got it in now. I guess I'll try getting it to the Kia Dealership north of me sometime this week. Their service center doesn't have the greatest reviews but it should be better than what I'm dealing with now at any rate.
 

·
Registered
2006.5 Kia Optima 2.4l 4cyl
Joined
·
9 Posts
Discussion Starter · #6 ·
Alright.
I took it to a second shop, they said the crank sensor was the culprit and that I needed Kia sensors, quoted ~$750. I picked it up, replaced the crank and cam sensors myself to save the $500.
The code cleared, it idles great again. Rode around a bit before filling up from a half tank at a gas station and it tried stalling on me when starting from the next stop light I hit. It missed a few times on the way home and stalled completely while I was turning into a parking spot. I had suspected that I went down an unrelated rabbit hole when I changed the crank sensor initially and I guess I was right.

I've seen where people have issues with the evap control solenoid, but I feel like that would be a more consistent problem than what I'm seeing. Thoughts?
 

·
Moderator
99 Kia Elan 1.8L
Joined
·
11,924 Posts
Everything points to a bad evap solenoid, but poor diagnostic skills by the service shops you've been using has cost you unnecessarily, and the Kia dealership would have been a better bet.

Also get the codes read at a place like Autozone - it sounds like your method of reading them isn't reliable.

Then if the codes don't shed any light on the current problem and you still feel out of your depth, find a reputable independent shop or the dealership.
 
  • Like
Reactions: Schmitty_Man

·
Registered
2006.5 Kia Optima 2.4l 4cyl
Joined
·
9 Posts
Discussion Starter · #8 ·
Hindsight being 20/20, you're right about the KIA shop. I shied away from the 2 Kia service centers in my area because they have very poor reviews but I don't know that it would be worse than what I've dealt with at this point.
Credit where it's due, this would have been a lot less complicated if I had taken it to a shop before trying to change anything myself.

I'll take it to AutoZone for the sake of being thorough but what makes you think my code reader is unreliable? I use it often so if I can't trust it I need to look at getting a replacement.

How could I troubleshoot the EVAP solenoids? The purge valve is easy enough to change but is the vent valve serviceable? Kiapartsnow shows that it's inside of a case with the canister assembly
 

·
Moderator
99 Kia Elan 1.8L
Joined
·
11,924 Posts
Hindsight being 20/20, you're right about the KIA shop. I shied away from the 2 Kia service centers in my area because they have very poor reviews but I don't know that it would be worse than what I've dealt with at this point.
Credit where it's due, this would have been a lot less complicated if I had taken it to a shop before trying to change anything myself.

I'll take it to AutoZone for the sake of being thorough but what makes you think my code reader is unreliable? I use it often so if I can't trust it I need to look at getting a replacement.

How could I troubleshoot the EVAP solenoids? The purge valve is easy enough to change but is the vent valve serviceable? Kiapartsnow shows that it's inside of a case with the canister assembly
The symptoms you describe don't match the error code that you posted - could even be that you didn't extract all the codes.

The evap solenoid goes by a few names, but don't change anything until you've done the diagnostics and the start of that is being sure that you have all the codes.


 

·
Registered
2006.5 Kia Optima 2.4l 4cyl
Joined
·
9 Posts
Discussion Starter · #10 ·
Sure thing. I'll have AutoZone check the codes this afternoon and see if I've missed anything.

I believe the p0035 code was legitimate but was caused by my replacing the sensor with an aftermarket part and, while it caused it's own problems (rough idle, more constant stalling), was unrelated to the issue I was seeing at the start. I feel like all I did was add another layer to my problem.
 

·
Registered
2006.5 Kia Optima 2.4l 4cyl
Joined
·
9 Posts
Discussion Starter · #11 ·
Hey all, sorry it's been a while since I've updated.
It has thrown a P0455 code for a gross EVAP leak but no accompanying codes. My understanding of the EVAP systems is a little more whole now and I think that if a solenoid were my issue it would throw the relevant code in this situation. I've checked my hoses under the hood and on the filler neck and didn't find any issues. Unfortunately I can't check the EVAP canister assembly as it's mounted on top of the gas tank and I'm not entirely comfortable dropping it with the equipment I have access to. I may try throwing an OEM gas cap at it, I don't trust the duralast one a whole lot.

I was careful not to fill the tank up all the way and put 1,000 miles on it without any issues aside from the P0455 code, but I filled it all the way this morning and it tried to stall on me once between the gas station and home. At this point my plan is to just avoid filling it all the way and take it to a shop for a smoke test when I've got the time. Maybe it'll throw a more specific code between now and then 😁

Thanks for all the help on this, I'll update you all when I do finally get this resolved!
 
1 - 11 of 11 Posts
Top