Funny or true? Changing spark plugs every 25 hours?

[GolgothA]

I'm in Texas, in 'the country' I suppose you could say (it's a 26 mile round trip to the closest Walmart and that is a little less than the distance to the next town)...

I just read the funniest (a hopefully false) automotive advice related to the PT Cruiser I've read on a site claiming to be legitimate: "Spark plugs typically need to be replaced every season or 25 hours of use." - so I'm supposed to replace my spark plugs every month?

I drive more than an hour a day EVERY day between work, kids, shopping, etc... Is this false information or am I really supposed to change my plugs every time I change my oil pretty much?

[rob302]

i think nitro changes his hourly. (joking)


i've attached page 1 of the maintenance schedule. for plugs it just repeats. 30k, 60k, 90, 120, etc, etc

[rob302]

when i changed my coil, wires, and plugs ~240k miles, they looked like this:


i changed them because the coil burned out..

i was happy they looked so bad. i figured the car would be faster and get better MPG... i mean the black one wasn't even screwed in all the way. amazingly, i noticed NO difference in any way. ran exactly the same.

car is not a turbo but i didn't exactly baby it. pretty much every green light i drive like this:

http://www.youtube.com/watch?v=95TXcJ_-MrQ

[NitroPT]

Spark plug changing advise has been being given for ever...since Fred Flintstone got his first car.

It is really from a DIY with limited testing equipment..when they look half as good as they did new like shoes change them.

Spark plug are one of the cheapest and easiest thing to change and have such a great effect on many aspect of the engine operating like ,power, torque,idle smoothness,throttle response and the big on. MPG!


There is not real advantage to winning the HOW LONG I HAVE HAD MY SPARK PLUGS in the engine without changing them.

Now from a data obtainable and viewable standpoint...well oscilloscopes don't lie. Keeping a clean or new spark plug in the engine which means more frequent changing than even the FSM is better.

[VsandFords]

I just read the funniest (a hopefully false) automotive advice related to the PT Cruiser I've read on a site claiming to be legitimate: "Spark plugs typically need to be replaced every season or 25 hours of use."


This looks like the recommendation for changing plugs in a lawn mower. Unless you have a drag mower that you are towing or maybe a belly mower on your PT , I think you could go a little longer before changing them.

[NitroPT]

I seasonally race my PT Cruiser. Last year I changed the plug every week when I get to the track. Some times it was twice a week if I went for a test and tune on wednesday and than a race on saturday. Most of those spark plug only had between a few hundred and a few thousands miles on them between races. I throw them all away.
There was a time I would actually clean re-gap old spark plug that did not have electrode wear. It was a little J C Whitney single plug cleaner that was battery powered. Back in the day some shops and parts stores offered free spark plug cleaning service. I just got to the point spark plugs that I use are so inexpensive I just buy dozens or cases at a time now.

[Handy_Cruiser]

I recently changed are the spark plugs on my Dodge Quadcab. I bought the truck new and these plugs had almost 230,000 miles on them. The electrodes were burnt down past the outer rim of the plugs and the gap averaged about a quarter inch. After changing the plugs, the engine ran about the same. And I wonder if I could have gotten another 230,000 miles out of the originals.

What's the moral of this story besides Handy being very lazy about maintenance on his truck? I think it's that in a good running engine that's never abused, plugs can last a very very long time. But besides being lazy like me or having the right equipment, time and the unnatural desire to monitor this, why take the chance? Plugs are cheap.

In most cases, the services manual for the PT tells the dealer service department to change the plugs every 30,000 miles. Of course, Chrysler may have just wanted to get their customers into the dealership before the 36,000-miles warranty ran out so they could try to sell them a new car. But I think that's a good rule of thumb for changing the plugs in our cars as long as the engine is running good and the car is never abused.

[cruserdad1976]

when I drive mine every day its around 1000 miles a week
so while I do change the oil every month I usually only change the plugs once a year and like already said I never really notice much diffrence

[NitroPT]

The funny thing about *FSM and DIY information is not accounting for the age of engine wear.
Having owned/operated an engine machine shop (Performance )others in the same line of business or worked in one would understand my statement!

*FSM=Factory Service manual , although I most often recommend and refer to the FSM for any and all procedures and recommendation unfortunately most all FSM do not take in account the wear factor of engines with regards to spark plugs and simply re-print generalities of decades posted information.
The forum thread title is interesting because time for maintenance scheduling of some parts may have its origin from Airplane required maintenance scheduling rather automotive? IDK as an A&E it was all about the logged engine running time.

[cruserdad1976]

Originally Posted by NitroPT

The funny thing about *FSM and DIY information is not accounting for the age of engine wear.
Having owned/operated an engine machine shop (Performance )others in the same line of business or worked in one would understand my statement!

*FSM=Factory Service manual , although I most often recommend and refer to the FSM for any and all procedures and recommendation unfortunately most all FSM do not take in account the wear factor of engines with regards to spark plugs and simply re-print generalities of decades posted information.
The forum thread title is interesting because time for maintenance scheduling of some parts may have its origin from Airplane required maintenance scheduling rather automotive? IDK as an A&E it was all about the logged engine running time.

well nitro my Chevy Silverado HD has a Hour meter and a Odometer and while there may some way be a way to compare the 2 unless you are sitting in heavy traffic every day for 2-3 hours id say im safe in just going by the miles

now on my Zero turn mower as well as my tractors they only have hours and its instructions are all based on hours run so on them I do try to stick to the suggested hours ran--however none of the above mentioned ever have plugs so...................................