Changing spark plugs.

[Sailing_Faith]

Getting the van ready for a couple road trips, I decided to visit the occasional "random misfire" code it has been throwing.

Changing the plugs was not that bad. No, really.... Maybe I have just suffered enough that I was expecting much worse, or maybe everyone had posted so much about it that I thought it was gong to be worse.

I did all 6 from below, used my normal plug wrench and an articulating head rachet.

No, really it was not that bad. I did a Chevy citation back in the 80s that was bad.... (Not proud of that).

Anyway,

I found the plugs that were in there actually looked pretty good. They were AC brand, with the number 12 printed on them. I replaced them with AC irridiums, but doubt there will be any noticeable difference.

After I started the job, I found the NGK Platnum plugs (split fire) that I had bought from a forum member a while back. I decided to leave the Irridium in there and save the NGK for next change... I will let you know how that goes in 60,000 miles (that is if I can still find them then).

I found the old wires (some 7mm generic replacement) had not been routed properly. They were too long and #2 had about a 3" burn where it had lain up against the manifold,

I will take some pictures, but wanted to remind others that it is important to route the wires carefully, and either use the factory wire securing points or tie then back well.

[Sailing_Faith]

Burnt plug wires..

[RECox286]

The wire sure looks like it may have been the cause of the code. Taking bets ?

Uncle Bob

[xit]

That would cause a miss, new wires for sure.

[Sailing_Faith]

I got sum big 'ole fat ones on ther snot.

I bought them here in the for sale forum a while back.

[Sailing_Faith]

The old plugs looked pretty good. No noticeable erosion on the tips (rarely seen in my experience with Platnum plugs anyway).

Here are the old plugs, AC deco with the #12 on them....

[Sailing_Faith]

One other thing,

The code is had was a 300 code, not a misfire on a specific cylinder. It is interesting to me that while codes are available for the ECM to choose from, this specific misfire caused a general misfire code.


Oh, and....

Dreading the job sometimes prompts me to get a quote from a shop on doing the work. I never put a car in the shop, unless something like an alignment is needed but I called a mechanic friend of mine and asked for the hours on this job. At his labor rate, it was almost $400!

[Sailing_Faith]

Ok, I lied.

One more, close up of old plug... Better view of tip.

[Leeann_93]

Is yours AWD or RWD?

I'd bet it was the wires causing the random misfire. Not just the burned areas, but the poor routing. These vans are picky about the routing.

[Sailing_Faith]

Yes, I suspect you are right. That might explain the 0300 code instead of a clyander specific code.

Weird thing, I started it and it ran great. The next day I drove it a bit and it was not running great. I thought I might have had a wire not on right... I read the codes and they were still from before... I had not cleared the 0300 code, and I live with various 4 series codes I don't have the current interest in fixing...

I reset the codes, and it has run smooth as silk ever since. Weird, it seems like the computer was doing something with the timing based on having thrown a code? Not sure i believe OBD II to do that though....

[Leeann_93]

Yup, it would do that. Don't you love OBD II?

[smokinjoe]

How do you reset a code? Just got new plugs and need to do that.

[Leeann_93]

On a '95? Disconnect the battery for 30 mins.

[smokinjoe]

thanks leeann gonna try it.

[Sailing_Faith]

Swapped out wires and cap today... had new plugs, since these have been in since I put the new motor in 52k ago....

Was pleasantly surprised when I pulled the first one to check it...

Plugs look great after 52k!

Just new wires and cap... even the cap looked great.

Ac delco cap.... contacts looked pretty clean.