gyates
Active Member
For the past couple of years my '05 has had an issue with somewhat erratic idle. I have had a couple of threads that I started on here with several very helpful suggestions, but none ever totally resolved the idle issue. Currently my truck has 87k miles, but on a whim I decided to replace the pcv valve and its related tube and elbow. I have driven it for a week now since the replacement and I have to say the erratic idle is solved!! Idle is perfect now!! When I removed the tube I was a little surprised at the amount of oil I found at the pcv valve end of the tube. Once I removed the pcv valve I did shake it and though it rattled a little bit definitely did not sound like a new one. My theory is, and I am not a mechanic so bear with me, but my theory is the pcv valve was sticking and was leading to my erratic idle at times (though at times it was ok). Interestingly a slight spongy feeling (also erratic) in my brakes is also now gone with a nice firm brake pedal!! I did pull the vacuum line from the brake booster to give me more room for the pcv repair so I guess it is possible that hose was not 100% tight, but bottom line is the erratic idle is GONE and brakes are firm again!! Hope this gives someone else a suggestion that is dealing with an erratic idle.
I think the recommendation is to change it around 60k. I have 87k and had never replaced it, but it definitely needed it. It is interesting how large a role the pcv valve has compared to its cheap price. If it sticks shut you will develop oil leaks due to pressure build-up in the block. On my daughter's Mazda 626 V6 it developed a valve cover gasket leak. Leak got really bad. I never even thought about the pcv valve but after doing some research I ran across an article explaining how a stuck closed valve can cause leaks. When I changed hers it slowed the leak down to a trickle. She has since replaced the valve cover gasket and all is good again!! Her car had 160k and I am pretty sure the pcv valve I removed was original to the car. My son-in-law is automobile clueless so I had to try and resolve it for her. lol!! But Wayne, as I mentioned in my original post the idle issue is what lead me to try and replace the pcv valve. I had been dealing with a somewhat erratic idle for at least 2 years. Not terrible, but it would fluctuate between about 850 and about 650 on the tach, even at times dropping down close to 500. Now it is idling dead on 750!!
