Kia Prado - Petrol Problems

check engine light on? have you hooked it to a scanner to check the computer? could be any number of things, thats where i would start.

could be O2 sensor Mass airflow sensor, ignition timing etc... scan the computer and get back to us.

I just fixed a similar problem on my Altima (no check engine light), but as the previous reply stated, it could be any number of things.

For me it was the MAF but I also changed the O2 sensor and temperature sensor first as they were cheap and possible causes. Luckily for me it turned out that some solder contacts inside the MAF had come lose, so I didn't have to get a new one.

You may also want to check fuel pressure as the fuel pressure regulator could also be an issue. Get a repair guide and measure everything that could cause this issue. For me measuring everything didn't help because the solder joints made contact when the engine was cold.

Often just checking all the sensors involved that you can does help and at least eliminates some possibilities. For my car unplugging the MAF caused the car to run at default value which can help identify the problem.

Good luck, and don't forget to have fun figuring it out.

On my old Toyota truck the fuel pump would leak when it got cold - and pump fuel on the pavement. It could be a similar thing - you might not see the fuel spill if it only happens at high RPMs. Try wrapping the fuel pump (the one under the hood) with rags and drive for some distance at high speeds and see if the rags collect anything.

You can also have a pressure test done on your fuel tank - it should be airtight. If not you could be venting your fuel as vapor. Since the tank is near the exhaust it might be the source of the odor.

Got to figure from previous postings you are working in a automobile repair facility outside of the United States so this can only be a very broad response. State side late model automobiles are OBD II compliant with built in diagnostic capabilities. A severe fuel problem would set several codes. Over fueling should also produce some degree of oil dilution as well as a very hot running catalytic converter. A hot/partially melted down converter would add to your fuel consumption problem. That said I would give a leaking injectors a yes vote but that wet cylinder should have shown it's self when you changed the plugs. I would also check for a fuel pressure regulator and verify it for proper operation.

In the past I have had units run cold due to cooling system problems and staying in open loop to long again the OBD II vehicle will help spot this trend also.

I guess finally go back and look at your old plugs and see what story they are telling you. A weak ignition that is letting a a plug or two foul will pass enough raw fuel through the converter to really light it up and bring on a severe restriction with really rotten performance.

Just a few thoughts

Hi

If you have petrol fumes from your exhuast this means your catalyst is failing, this can only mean a serious fueling problem as it should be able to cope with minor problems. Most cars have what we call a limp home mode where if a sensor or fuel managment component fails it will disregard any closed loop info and return to open loop running mode. (a failsafe fuel and ignition map) but this should trigger a warning light. As it has not you may want to carry out a compression test as this is also a symtom of valves leaking or low compression.