I haven't changed spark plus in 4.5 years

Going by my Service Manual for my 2003 Ford sedan...my plugs are good for 100,000 miles. I might change them around 60,000 though...maybe...have to think about it.

First coolant change is at 48,000 miles. After that, every 30,000 miles. Although DEALER said first change is at 30,000 miles ( that isn't documented anywhere though ).

Right now, I'm at the 24xxx mile mark, according to the odometer. I'll just keep running it until the right numbers show up.

Lg

Plugs don't really wear out from sitting, but you do tend to "become one with" the heads. I would change them for no other reason than to stop them from seizing and making a nightmare later on.

What kind of coolant is in there? Old green stuff or the new long life kind? I like to change the green stuff every other year. I only have one car with the new orange stuff and I have been changing it on the same schedule just because I don't trust anything new.... Your antifreeze also has anticorrosion protection. While the freeze protection may still be good the anticorrosion protection is likely gone.

Also consider flushing the brake fluid. Brake fluid absorbs water from the air and the water will cause you rust and corrosion issues which seem to be a lot worse on the vehicles that sit a lot. I flush the brake fluid every other year as well.

Steve B.

Plugs, wires, caps and rotors need to be changed at the manufacturer's recommended interval or at least inspected and tested upon the manifestation of any symptoms of a 'miss'. As plugs age the gap (resistance) increases causing the coil(s) to load heavy and fail prematurely. If enough resistance either through wires or plug gap or if grounding develops you'll notice a secondary ignition miss usually diagnosed by driving up a hill with the converter locked at a steady load. You'll feel a shudder or miss which may not be noticeable any other time.

Much discussion in the industry about extended life coolant but best to err on the side of safety by change coolant every two years (IMHO). As Steve B. stated antifreeze eventually looses it's anti corrosive qualities sometimes allowing an electrolytic action to begin in the engine often sacrificing the freeze (core) plugs or the water pump impeller. Depleted coolant may not allow your engine to freeze up but it does other bad things.

Brake fluid is hygroscopic and must be tested for water absorption. Too low of a boiling point will not only endanger your stopping ability but will play hell with some ABS systems. Brake fluid can look great but be moisture laden. Get it tested.

I would suggest fuel system cleaning every 24,000 miles. Use a system which both cleans the rail and injectors restoring the correct spray pattern. I prefer a two line system in which your fuel pump is disabled and your engine runs via the cleaning machine which can de-carbonize as well. Avoid the 'pour into the gas tank additives' as they are not usually strong enough to restore clogged injectors. Instead use a 'top tier' gasoline if available in your area switching between two or three brands every five thousand miles as the detergent additive in gas is paramount in maintaining your fuel injectors and intake valves. Avoid cheap no name gas. The penny or two you save in immediate fuel costs will more than likely cost you two or three fold in the long run. Best regards

mac wrote:

Plugs are probably not a high priority. I would change these fluids: Brake, cooling system, transmission, oil, power steering. What's the interval for cam and accessory belt changes. If they haven't been changed I would do it now.

mac wrote:

I think of spark plugs as degrading as a function of mileage and engine condition (too rich? too lean? burning oil? detonation?...) rather than time. Why not pull one and see. The repair manual have charts of what you can infer from their appearance. I'm guessing that at 20k they're alright, on a modern car with high-energy ignition and closed-loop engine controls. Bu seeing is believing.

The contacts betwixt cap and rotor (dunno if this applies to you, but it remains in use as a convenient physical format for distributing high voltage on a lot of newish engines) might be getting a little crunchy by now. This is an easy visual inspection.

Plug WIRES can degrade from age as well as mileage (indirectly, because of engine heat) but at four and a half years (assuming they were changed at the same time as the plugs) they're probably okay unless you live in hard desert.

How old are your hoses (including little ones in obscure places on some models), thermostat, and radiator cap?

Just some thoughts, worth what you paid if your connect time is cheap,

--Joe

Thanks for the replies. Sounds like it's time to change the coolant (flush???, or just replace???...about $50 difference in price) . As for the spark plugs...maybe.

In answer to some of the questions: Cap wires and rotor were changed once before (7.5 years ago...63000 miles ago). I guess I should have asked....Is it time to replace those too???

Brake fluid, trans fluid....all done recently (relatively!!).

That's a good question!! Because I'm starting to look for new repair shops (not worth using Dodge dealers anymore), I just went to a shop ("shell") that looks good (and with good ratings from "consumer checkbook", and in a preferred location) and asked them a few questions. The manager (who also says he was a tech for a long time) told me I need to find out what kind of coolant was put in there last time (extended life vs. "regular") because that's the kind that should be put in next time--he

said it's bad to mix the 2, even if he flushes the old out...does that sound right so far?..doesn't sound right to me, but .....). But he didn't give me any suggestions on how to find out what's in there! He told me the green/orange color difference won't show up for old fluid that's already in the truck. Of course, if i call a dodge dealer that put the fluid in 3.5 years ago, they're going to say...How would i know what was done 3.5 years ago. I suppose I should look at my manual for the kind of fluid that's required, then assume the dodge shop put that in there, right?