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Juan Crespo
Juan Crespo, Tech Trainer
Category: Kia
Satisfied Customers: 1513
Experience:  A.S.E. Master Technician, Advanced Level, Emissions - Asian, Domestic, & European
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I have a 2004 kia optima 2.7 it use to start, drive then

Customer Question

Hello
I have a 2004 kia optima 2.7 it use to start, drive then shut off after 5-15 min driving or idling now it does not start at all just cranks. i can hear the fuel pump priming and have tested for spark - no spark on 2 cylinders i checked . it did have 2 codes for crank sensor n throttle sensor both have been replaced b4 the no start condition with out any change in running time b4 shut off. after no start condition i also replaced cam sensor coil pack, plugs, wires, n coolant temp sensor
Submitted: 2 months ago.
Category: Kia
Expert:  Mike V. replied 2 months ago.

Hello and thank you for your question!
My name is ***** ***** I will be assisting you with your question today.

Expert:  Mike V. replied 2 months ago.

do you still have any codes?

Customer: replied 2 months ago.
no i have reset ecu n not had car running since
Expert:  Mike V. replied 2 months ago.

That's ok, it doesn't have to be running to store some codes. As long as the computer is powering up.

I would start by checking the timing belt, if you can, take the oil fill cap off and have someone crank it. Make sure at the very least the cams are turning.

I know you said it's not getting spark, do you have a test light or volt meter so we can check and make sure the coil is getting power to it?

Customer: replied 2 months ago.
i have both tools n i have already taken the covers off n checked all the timing marks r good.
Expert:  Mike V. replied 2 months ago.

Ok, give me a moment to pull up the wiring diagram to see if we can test the wiring to the coil and the cam sensor.

Does the check engine light or service engine light come on when you turn the key on?

Customer: replied 2 months ago.
check engine light comes on
Expert:  Mike V. replied 2 months ago.

Good,

first, lets take a look at the cam sensor. 3 wires, one wire should have battery voltage, one should have continuity to ground and the center wire is the signal wire.

In the diagram, pin #1 is the ground, #3 is the power, #2 is the signal wire, which I do not think you really will see anything on unless cranking the engine

Customer: replied 2 months ago.
on mine 1 has 9.47 power n 3 has 9.52 ground
Expert:  Mike V. replied 2 months ago.

Can you explain to me how you are checking for continuity to ground please?

Customer: replied 2 months ago.
positive battery terminal to #3 plug terminal
Expert:  Mike V. replied 2 months ago.

Good enough, should mean you have ground.

Lets do the same with the crank sensor.

heres another diagram

I think you should check the battery too, it should be closer to 12 then 9

The pins are the same, 1 is ground, 2 signal and 3 power.

Customer: replied 2 months ago.
same 1 is power n 3 is ground
Expert:  Mike V. replied 2 months ago.

Ok, is the battery voltage actually only 9 volts?

If it is, I would try a jump start. Some of these won't fire the coil and injectors unless the engine is cranking at least 250-300 rpms. If the battery is that low, it might actually not be turning on the pulse and ignition

Customer: replied 2 months ago.
tryed jumping it , still no start. when i had the cables hooked up the sensors where reading 12 instead of 9
Expert:  Mike V. replied 2 months ago.

Ok

clearly then the battery is weak, you should charge or replace it. No, I don't think it's the problem if the car won't start, but, still trying to get it running with a low battery isn't helping.

Can you check the pink wire at the coil for power with the key in the run position please and let me know.

Customer: replied 2 months ago.
12.4 with the battery cables connected
Expert:  Mike V. replied 2 months ago.

Ok

At this point I am unsure where to go next.

I am going to go ahead and open this up to the other experts. Please don't reply or rate because it will lock it back to me and nobody else will see it and be able to try to help.

Sorry

Expert:  Juan Crespo replied 2 months ago.

Hi there. Different expert here.

Nowadays, this type of diagnosis requires using a capable scan tool that can communicate with the ECM and tell us what the issue is, and a lab scope to verify that information.

If the scan tool and scope are not available, we can go by the fact that often times coils go bad and loose resistance; when that happens, primary ignition circuit amperage increases and damages the transistors in the ECM that switch it on and off. So, if crank sensor signal and primary ignition circuit power are both OK and still there is no spark, then the most likely culprit is a bad ECM.

Customer: replied 2 months ago.
ok so if i get a new ecu it will fix the problem? also does the new ecu need my cars vin programmed into it to be usable?
thank you
Customer: replied 2 months ago.
or is the new ecu just plug n go?
Expert:  Juan Crespo replied 2 months ago.

A new ECM will most likely fix the no start issue. However, if you need assurance, then the system needs to be checked using a capable scan tool such as, or equivalent to the GDS. That same scan tool will be needed to program the new ECM.

I wish there was an easier way to diagnose and repair these issues. The fact is that car manufacturers have designed their vehicles to be brought back to their dealers for service where factory-trained technicians using vehicle-specific tools and equipment can do the work.

Best Regards.

Customer: replied 2 months ago.
what does gds stand for also can it work on all cars or just kia
Expert:  Juan Crespo replied 2 months ago.

Global Diagnostic System is a PC-based tool that is used to diagnose and program onboard modules on Hyundai and Kia - click here to view an example from AE Tools.

Customer: replied 2 months ago.
ok i already ordered the ecu and it just arrived in the mail today ill take it to the dealership to have it reprogrammed tomorrow
Expert:  Juan Crespo replied 2 months ago.

Is the vehicle drivable or are you towing it there?

Customer: replied 2 months ago.
i will be towing it their due to no start issue
Expert:  Juan Crespo replied 2 months ago.

I got it. My advice is to give them a call before you do; sometimes dealers get cranky when you don't purchase the parts directly from them.

Best Regards.

Customer: replied 2 months ago.
is this the correct tool ? http://www.ebay.com/itm/Software-V15-GDS-VCI-Diagnostic-Tool-for-Hyundai-Kia-with-Trigger-Module-Blue-/172111544699?hash=item2812a5c17b:g:GsgAAOSwuAVWy9Gk&item=172111544699&vxp=mtr
Customer: replied 2 months ago.
or can i download the gds software onto my laptop and use my usb to obd2 cable i have to reprogram it?
Customer: replied 2 months ago.
or can i download the gds software onto my laptop and use my usb to obd2 cable i have to reprogram the car?
Expert:  Juan Crespo replied 2 months ago.

Sorry for the delayed response - I usually log out by 8 PM

I looked at that ebay ad and noticed the tool is a knock-off from China with no manufacturer information or an identifying part number - all I can say is "caveat emptor" (buyer beware)...

The GDS I'm familiar with is proprietary and only available to Hyundai and Kia dealers.

Customer: replied 2 months ago.
hey got the car reprogrammed from the dealer and it still wont start.not to mention wasting $127 what else could it be?
Expert:  Juan Crespo replied 2 months ago.

I've actually never heard of a dealer programming a new PCM on a vehicle that wouldn't start to begin with - how would they confirm the programming? I'll opt out and reopen your question to the field. Please don't rate or reply until another expert responds or the site will cycle this back to me.

Customer: replied 1 month ago.
this problem is still not fixed, please help. im getting p0335 even thow i have already put a new crank sensor in