Nissan Altima 2.5S - Spark Plugs Issue
 

HI,

Car has 138K miles, we have been performing maintenance since 95K just bought at 80K. We had been advising him to replace his spark plugs since 120k. At 136K he had us replace the plugs stating at the time it was hesitating. It had codes for misfires on cyl1 and 4. When we replaced the plugs we noted that the diodes on the plugs from cyl. #'s 1 and 4 were bent over. We scoped the pistons and found no marks and made notes then replaced the plugs making sure to use the correct oem plugs which were the same plugs we took out. Six weeks later the customer was returning from a middling long road trip and noticed the hesitation return. We reexamined the plugs and found that cyl#1 plug had been bent again and the porcelain was cracked, but not 4. Customer states no head job ever done. Carfax doesn't show any history of it. Never had this issue before 136k. There is no unusual noise from engine when running, plug is not crushed, no marks on piston head. Obviously there could have been headwork done prior to his purchasing the car but I am surprised if that is the case that this problem waited so long to show up. I am at a loss as to how to proceed. Pull the heads and send them to a machine shop? Can they measure how much if any has been milled? Is there an adequate way to measure piston stretch? Suggest engine replacement? How do I advise my customer? As a temporary fix we have added a washer to the plugs in question and have advised him that we will research the problem.

Please help.

I did not find the right solution from the internet.

References:
http://www.managerforum.net/viewtopic.php?f=67&t=9154
Online Video Service

Thanks!

Addition of washer(s) would also have been my solution. If it works, leave it like that and leave the head on. :gut: