Assalam-o-alaikum to rest of the Liana fans and owners at Pakwheels
Yesterday I changed the coils on my Liana. Since the previous gadha owner had directly given 12 volt supply to one of the failing coils, there were no misfire codes on my Liana even though it was misfiring. I could feel the misfire when listening closely to the tail pipe and feeling the exhaust gases with the palm of my hand. So I finally did it with the help of Allah.
Here is what I did:
1: Took the plastic cover off.
2: Noticed that I have no socket that is long and slim enough to go inside and take the plugs out
3: So rushed to Bilal Ganj and bought my very own 16mm slim goti (I have my own set of sockets so already had the handles)
4: Undid the plugs. They were pretty tight so I had to do it carefully. Now, the plugs won't come out as they were deep inside the plug holes so I grabbed an old speaker and with the help of its magnet and a ratchet, took them out one by one with its help.
5: The 2 middle plugs were OK and that told me that this coil was good. However the left and right most plugs were soaked in petrol. This was the coil whose plug wires were directly getting 12 volts from the battery via a hook-up wire, through a relay. So this was the culprit coil.
6: But then I noticed that two of the plugs were covered in engine oil near the white part. i.e., their tips were dry as a bone but their white ceramic part was covered with oil, so this told me that the tappet cover gaskets are leaking.
7: The only reason for the tappet cover to leak is mostly a clogged PCV valve. And when I pulled the valve out, it was indeed clogged, completely filled with engine oil. Perhaps the damned previous owner didn't even know that this plastic piece of white pipe was a valve which needed frequent replacement. anyway...
8: Went to MontGommery road and bought a brand new tappet cover rubber gasket. Japanese. Cost was PKR 750. It included the tappet cover gasket as well as the 4 rubber ring gaskets for the spark plugs. Also bought a new PCV valve (PKR 1200) and a set of wiper blades (PKR 750) as mine were worn out quite badly.
9: Took the tappet cover off and pulled it out. Cleaned the area where new gasket would be seated. Also cleaned the tappet cover with a clean cloth wrapped around the tip of a small flat-head screw driver.
10: Installed the rubber gasket with the help of a few drops of elfy so that it wouldn't drop inside while I would be in the middle of installing cover back.
11: Installed the cover. Then with the magnetized ratchet, put new spark plugs into their holes (NGK BKR6E11, PKR 250 per piece) and tightened them up.
12: Pulled off the wiring connections for the previous bad coil and taped the wiring itself up with fresh tape for better insulation. Then added a thick layer of silicon around the new set of coil connection wires and installed the new coils (Tested the wiring harness first and it was OK, without the relay! )
13: Installed the new PCV valve and then put the plastic top cover back on.
14: Started my car up and she started up in like half a second. Idled beautifully and ran stable.
15: Threw the junk coil and connector wire into the dustbin and cleaned the mess up. I've kept the good coil and wiring with me just in case. The coil I removed from the car is a Denso one. The ones that I installed are YEC (PKR 4500 each).
16: Grabbed my car scanner and scanned for any codes just for the sake of it. :d And there were none Alhamdulillah.
Here are a few pictures Sorry for bad lighting.
Here is the bad coil:
Here is the good coil which I've kept for bad times:
Here is the bad PCV valve:
Tools that were used