Cylinder 1 Misfire and Oil on Plugs

Johnny78Blaze · Post by **Johnny78Blaze** » 22 Jul 2011, 16:36

I’ve been getting oil on top of the valve cover. Also light smoke coming out of dipstick. I’m assuming I need to replace or clean the PCV. I left the black cover off of the valve cover to monitor the oil (easy access to plugs). Plugs were recently changed and gapped accordingly. Car is running rough in low gear and check engine light is on. Misfire in cylinder 1. Cleaned oil off of the plug threads in cylinders 1, 2 and 3. Any suggestions as to what is causing my misfire in cylinder 1?

Codes:
4-5-1 Misfire Cylinder 1
5-4-3 Misfire At Least One Cylinder
5-5-1 Misfire Cylinder 1 / Three-Way Cat Damage
5-4-5 Misfire At One Cylinder / Three-Way Cat Damage

Just did Seafoam treatment today. Didn’t seem to help.

Should I clean the PCV or replace it? Trying to save money. Also, how important is it to have the black cover on over top the plugs and valve cover?

Post by **Ozark Lee** » 22 Jul 2011, 16:53

The spark plug cover is more decorative than functional - you aren't hurting a thing by running without it. Have you run a compression test on the number 1 cylinder?

...Lee

Post by **erikv11** » 22 Jul 2011, 17:19

Agreed, you ASAP want to check compression in #1.

While the car is running, if you pull the #1 plug wire can you get it to spark to the valve cover?

Johnny78Blaze · Post by **Johnny78Blaze** » 05 Aug 2011, 04:10

Going to run a compression test asap. Will get back to you guys.

peacock · Post by **peacock** » 05 Aug 2011, 05:56

the oil leaking from the oil cap / that pcv vent tube / spillage from messy oil changes can get into the cyclinders and penetrate past the plugs and cut off your spark.

Post by **jblackburn** » 05 Aug 2011, 07:53

Is the plug on #1 firing? Pull it out, leave it connected, and ground it to the block.

If the oil cap seal is leaking badly enough, a crap ton of oil can get down in the plug holes on #1 and 2 and drown the top of the spark plug in oil.

Johnny78Blaze · Post by **Johnny78Blaze** » 22 Nov 2011, 17:33

I know it's been awhile since I posted here but I started a new thread about PCV kit and such. Anyway, I did the kit and now getting misfires in #1 and #4 and high turbo boost pressure. Just got new compression tester today so I'll have numbers by the weekend.

Post by **Ozark Lee** » 22 Nov 2011, 17:43

When you do the compression test do all 5 cylinders. The quality and accuracy of compression gauges is pretty horrible until you get into the big dollar gauges but the consistency between all 5 cylinders will be more telling. My gauge is always at least 50 PSI lower than what I think it really is but it is a Harbor Freight compression gauge from some unheard of province in China.

If the car runs and the compression gauge says they are all running at - say 90 PSI - then we can just figure that the gauge is wrong. The important thing is the numbers between cylinders and how they match up.

...Lee

Johnny78Blaze · Post by **Johnny78Blaze** » 22 Nov 2011, 17:49

Exactly Lee....I'll keep you updated. Thanks again.

Johnny78Blaze · Post by **Johnny78Blaze** » 23 Nov 2011, 16:03

I used my kit's long extension bar for the first four cylinders and used the small adapter for cylinder 5. 5 was a lot higher than the other cylinders. I remembered afterwards that I forgot to have the throttle opened all the way and redid the compression test on all 5 cylinders. Lee, with the extension bar my numbers were roughly 50-60 psi lower than with the regular adapter. So, I used the regular adapter for all 5 cylinders and got much better and seemingly accurate results (my tester is from Taiwan) all while keeping the throttle wide open. Here's what I came up with:

Cylinder 1 - 168 psi
Cylinder 2 - 175 psi
Cylinder 3 - 173 psi
Cylinder 4 - 175 psi
Cylinder 5 - 167 psi

Cranked about 10 times for each and the pressure jumped gradually. All in all I think they're not bad numbers. As far as the 'gradual' pressure jumps, I think I probably have worn piston rings. I'm sure this is now not the reason for my misfire situation. I'm going to order a fuel pressure kit and check my fuel delivery system thoroughly. Hoping it may be something as simple as a new fuel filter. Haven't changed it at all in almost 3 years. I'll update after I check the fuel system. Any other suggestions are very welcome. Thanks again.

Also, after the compression test I took it for a drive down the road, reset the CEL and drove it home. Only codes coming up are for a misfire in cylinder 4. No code for cylinder 1 or code for high turbo boost pressure. It could only just be a matter of time as well for those to pop up again.