[HatinLife76]

Ok, I bought an 04 Kia Sorento EX 3.5l automatic 2wd with about 120k miles a couple of months ago from an elderly couple; nothing was wrong with the vehicle except that it needed new tires, valve cover gaskets, and just a basic tune-up. A month of having it on the road the car just died as I was sitting at a light. It started back up but died before I could even complete the turn and wouldn't start back up for nothing - still hasn't. It seemed like the vehicle just kinda stumbled and died both times. I had no previous issues with the vehicle and the prior owners hadn't really drove the car in just over a year and had no problems besides an oil leak that I already corrected. With that being said, I changed the crank and cam position sensors - no dice either. After doing a little diagnostics I noticed that the tachometer wasn't moving when cranking, the MIL/CEL light wasn't illuminating when key was inserted and switched to the ON position, I had no 5v reference signal to the ckps, cmps, and another sensor or two. The coil packs were receiving 12v, though. I checked the timing and everything lined up perfectly, so I'm a little confused.

With all that being said, I'm fairly sure I have a short somewhere. If anyone can give me some guidance on how I would go about fixing this issue it would be immensely appreciated. I don't think it's the ECU/PCM/ECM since I ordered a remanned one that was programmed to my VIN and still had the no start issue. I'm hoping someone can walk me through the process of narrowing down the issue and have some wiring diagrams as well. I have checked all the fuses and relays (I think I got them all), so everything is kosher on that end. And, I believe, that's everything that I can think of.

New Parts: Plugs, wires and coil packs, crank and cam sensors, air filter, fuel filter, oil and filter, and a new radiator and expansion/overflow tank since the original ones looked like a future issue.

Diagnostic Tests: Fuel pressure, fuel injectors test, compression test, spark plugs, and an El cheapo scanner that gave me a couple codes to do with the crank/cam sensors (I wrote them down but, as usual, I cannot find them and I already cleared the codes.

I hope that all of this info will help someone pinpoint the issue and help me out before I decide to use the car as target practice! (;p) Thank you for any help you provide.

 

[HatinLife76]

Have you tried starter fluid?

When last was the timing belt changed.

You say that you've checked the timing, but symptoms point to a timing issue.

I currently have the timing cover off and all 5 markings are dead on. I don't think the timing being even completely off would cause a no reference signal to the crank and cam sensors. Tried starter fluid; it kicked over, ran horrible and I had to keep my foot on the gas peddle or it just immediately died.

 

[HatinLife76]

Have you checked continuity on the harness wiring. The wires to the crank sensor, particularly, can degrade with age and heat. They become vulnerable when the sensors are changed. Just a thought.

No, not yet. That was my next project. I just got the extra long jumper wires yesterday so I could check. If that's not the issue than the problem is between the ignition and the ECU (or even the ECU itself, which would be incredibly odd since I tried a remanned one programed to my vehicle and nothing changed). I'll let you know how it goes with the continuity check no later than this weekend.

 

[HatinLife76]

I did some quick poking around, this time going through the system a bit slower. I found out that my MIL/CEL bulb was burnt out, so nothing of concern there. Next, I noticed that my Main Control Relay was not getting power (it was not being energized to kick on), which killed the 5v reference for my crank and cam sensors. I jumped out the Main relay and tried to start it, still nothing. I pulled a plug and left it in the coil, cranked the engine and found out that I still have no spark. I am unsure if I was getting fuel or not, didn't check. So, I'm left with a bad ECU, malfunctioning Immobilizer, or a bad ignition switch. I'll have to narrow it down more tomorrow; I'll poke around the immobilizer first, then the ignition switch since they're practically right next to each other. Any advice is always helpful. Thank you.

 

[HatinLife76]

I did some quick poking around, this time going through the system a bit slower. I found out that my MIL/CEL bulb was burnt out, so nothing of concern there. Next, I noticed that my Main Control Relay was not getting power (it was not being energized to kick on), which killed the 5v reference for my crank and cam sensors. I jumped out the Main relay and tried to start it, still nothing. I pulled a plug and left it in the coil, cranked the engine and found out that I still have no spark. I am unsure if I was getting fuel or not, didn't check. So, I'm left with a bad ECU, malfunctioning Immobilizer, or a bad ignition switch. I'll have to narrow it down more tomorrow; I'll poke around the immobilizer first, then the ignition switch since they're practically right next to each other. Any advice is always helpful. Thank you.

Quick edit: Trouble codes P0727, P1121, and P1631 are on my ECU/PCM and cannot be erased. Hope someone on here sees this and goes, "Oh! I know what's up with your car!". If so, please enlighten me.

 

[HatinLife76]

At last you may be getting somewhere. For my money (which isn't worth so much these days!) I would still plump for an electrical issue (Open earth?). This may be simply down to a bad harness connector, but they are really hard to track down. Until you can be assured you have good connections, please don't throw more parts at the vehicle .....

There are numerous posts (even on this forum) regarding the P codes you have. Especially P1631, which is an odd one. I presume you are in USA??? Then your 2004 should not have an immobiliser which is one problem area for that code. Therefore, something else would be causing a FAIL signal to the ECM (The fact codes are still there indicates the ECM is working) and it is retaining the FAIl signal. Start (fuel/ignition/injection) will remain deactivated until the fault is corrected. ie you will not get the signals you are expecting because of the FAULT, not because the control boxes are not working.

If you are searching on Google try explicitly mentioning Kia (eg "OBDII code P1631 - Kia Sorento" ) to narrow down the results to your vehicle type since each manfr will have there own take on the code. (It even varies between countries - even our old 3.5V6 models had immobilisers and diesels have entirely different systems.)

Yeah, I'm in the US; also, the vehicle is equipped with an Immobilizer (maybe it's a late model 04?) - you can see it when you remove the Crash Pad Lower Panel, it's just to the bottom central console, driver's seat. And funnily enough (heavy sarcasm here), the scanner can no longer read the ECM. The only parts I threw at the problem were for the crank and cam sensors, the other stuff was for routine maintenance. But, I am going to take your advice and check the necessary grounds. I disconnected the battery and left it that way over night, just to make sure I'm working with a solid foundation. I'll reconnect the battery when I continue later today. Thank you for the advice you've given me so far.

 

[HatinLife76]

I was just about to update. I thought I've seen some hack jobs in my life but this takes the cake. About the immobilizer, it was not supposed to be in my vehicle. I pulled it out from under the dash, wanting to run the numbers. It wasn't even hooked up to a damn thing! It has the connector and wires from the vehicle it came from still plugged in, an 07 Sorento! I checked all of the connectors that I could find to make sure they were tight, and decided to take a nap before I said to the hell with it. Oh, the immobilizer was sandwiched against a steering module, just zip tied. But, you were right about the deterrent system. Now it's down to why the main control relay isn't receiving a signal to power the MFI circuit. All the grounds in the engine bay are solid, which leaves under the dash to be checked next. Thanks again, G6!

 

[HatinLife76]

Sorry, for the lack of updates but I started a new job and I've been playing phone-tag with the prior owners. It's been like pulling teeth with them! All I asked is what modifications they where doing/did to the car - took 3 days for them to tell me they were trying to install a deterrent system from an 07 Sorento that their mechanic didn't finish. Yeah, my main harness being maimed kinda said that much! So, this is being put on the back burner until mid-January at the latest.