[Blkid]

Hi,
from about 3-4 months my kia rio 1.4 dohc have a very high fuel consumption (8km/l urban, 11-12 on the highway) and loss of performance (the engine have many difficult to accelerate also with transmission in neutral) . I changed the spark 2 months ago without results. Yesterday i removed the spark and i noticed that all the 4 spark are black and also the piston head (in the part visible by the spark hole) is very black and wet. Now i already changed the spark (the previous was bosh super plus FR 7 DCX+) with ngk BKR5ES-11.

Today with new plug the engine seemed slightly more responsive (or is a placebo effect!!!!).

On the web i read that the problem maybe a too rich mixture. What do you think could cause this problem? Lambda sensor, Map sensor or other????

The engine check led still goes off, so for the ecu there aren't problem....

 

[Blkid]

Hi,
last saturdaty i checked some sensors on the car. The hole in the MAP sensor was clogged by oil deposits. I've descaled it with wd-40 and cleaned with alcool and cotton-fioc. Now with 1/4 of tank i traveled for 140km. Previously i couldn't reach 100 km. I don't know if are the new spark or the dirt map sensor (or just luck!). I'll see these days how it goes fuel consumption.

 

[Wry 'Cuda]

Hi,
Last saturday I checked some sensors on the car. The hole in the MAP sensor was clogged by oil deposits. I've descaled it with WD-40 and cleaned with alcohol and cotton-floc. I don't know if it is the new spark plugs or the dirty map sensor (or just luck!). I'll see these days how it goes fuel consumption.

Unlikely to be caused by spark plugs. Bad fuel is a possibility. Try some high Octane fuel from a different servo.

 

[Hypsy]

Too rich a mixture will definitely foul out the plugs pretty quick, and dirty plugs won't fire as strong, thus allowing more fuel to go unburnt which will cause that nice soot build up that you're seeing.

Oil in the MAP sensor will certainly cause some faulty air/fuel ratios, and causing the exact symptoms you've been seeing.

 

[bigbfarm]

You really should pull any stored obdII codes. I'm guessing a sensor is sending faulty signals that are affecting the fuel/air mix.

 

[Blkid]

Actually my car seems to go better.... It regained performance and gasoline consumption has a bit dropped. I also changed the fuel filter, since they were passed more than 6 years and i made ~70.000 km (the service manual report to change it after 5 years or 75.000 km) . The engine failure led is not on, so i don't think that there are stored error codes.... If i can found the obd2 module (i see it on ebay) i will made a diagnosis...

 

[Blkid]

This problem has no meaning. With the same fuel servo with the same road, one day i have performance problem and high consumption, another all goes ok.

In the last week i left for a travel with my car. I left thursday to come home and the car was a disaster, with an average less than 10 km/l without ac. Yesterday with ac on for all the travel the average of consumption was 14 km/l.Same cruising speed, same driving style and same road.

I don't know what to think

 

[DavesSpectra]

The MAP sensor is very sensitive to what is put on it and is sensitive to being touched by anything (cotton-fioc)... WD-40 and alcohol should not be used in this area..
The do make a MAP sensor cleaner in an aerosol can that is safe for this sensor. Spray it on and let it dry.
I hope you didn't damage the MAP sensor. You can try a used one from a car junk yard.
Dave

 

[Blkid]

the map sensor is located in a location with oil deposit, oil vapor and high temperature.... I've cleaned it without using forse.... However, i'm tired of the problem and i decided to install a gpl inition system and the mechanic have decided to test the car 2 or 3 days to make a dyagnosis. If it doesn't find nothing, it will install a black box at the obd, before install gpl inition, to see if there is a real problem.... Also i've changed fuel reseller and the problem is much reduced. Now it have 10 km/l in city and 12-13 in highway with ac, so i think that was a mixture of wrong spark plug (the previous had a wrong thermal grade), map sensor and bad fuel....

When the gpl installer will make the diagnosis I tell you if it finds something

 

[Blkid]

Hi,
i want to update the thread.... I didn't find the cause of problem and the installation of gpl has failed for money problems!!!!


However recently the problem of high consumption and loss of performance is worsend. Also we noticed (me and my mechanic) that the intake chain problems is worsened. My mechanic thinks that the chain problem maybe the cause of the problem, also because the camshaft position is readed on the intake camshaft and the increase of chain slack may cause engine timing failure... Actually the engine has also changed noise, expecially when i start the a/c, roars like a ferrari :lol: and the chain beats strong.

I ordered the chain kit (the 2 camshaft toothed gears, new chain and plastic guide) that, among other things, is modified by kia to solve the thiking noises and, for me, also timing problems.