02 V6 Spark plug, driver rear only, consistent signs of coolant burning

[Christobal]

02 V6. When I changed the first set of plugs and wires (late) at around 108K, first signs of missfiring, I noticed the driver rear, cant recall cylinder numbering for this engine and it's not on sticker under the hood, was dry but had white chalky buildup.

It's now at 154K and I notice a slightly rough idle at times and some hesitating, missing at low rpm in OD...lugging. I just pulled the three driver sides...Autolite Platinums AP 103 IIRC. Sure enough that driver rear is chalky and a bit corroded looking. I filed it and regapped it though gap was similar. I set em all at .045 when new after finding the 100K+ Motorcraft Platinums at .070-.080...yikes. All the left sides were still at .048-.050 or so...pretty good for at least 30K miles.

Also had what I believe was some dielectric grease residue in teh boot and on the connector end of the plug and wire end on the driver front...cleaned it and twisted it around metal on metal to make sure raw metal contact.. not sure if this was an issue at all. Test drive....miss went away.

Seems to only be using 8 oz every 3-6 months or 3-5K miles...not much really, I actually haven't added any coolant since radiator was changed prematurely imo, (out of my control) at about 125K. I just let the resevoir run low.

I am considering putting some non-media non-metalic stop leak in there, looks like it will mix in within a few hot cold cycles.

I had trouble with the driver middle and rear on a 93 V6. I changed the factory cork intake manifold gasket with FelPro rubber and it seems 80-100% gone, I was getting pinging and wet plugs with oil and coolant. That engine still pings more than it use to and should, but much less so than when I had the problem.

1. Does the 03 OHC motor have wet intake manifold gaskets, oil and or coolant?

2. Head gasket torque issue from factory? Heads should have been re-torqued, might be a slight seepage somewhere?

One way or another, pretty sure it's just coolant and just that driver rear hole.

When changed the right side plugs seemed cleaner/better shape overall than left sides. Maybe that left head or some other production tolerance or build issue? left side seem to get slightly dirtier front to rear with that rearmost being chalked up to the point of misfire after 25K-30K.

My recollection ...in the notes somewhere, just don't care to look...somewhere around 50-100K is when the slight coolant consumption showed up. I have never seen any on the outside of the engine or on the ground.


Thanks for your input

Chris

 

[Christobal]

Anyone have mysterious coolant consumption or intake manifold or head gasket issues on the V6? I have a feeling there's a production tolerance issue or head bolts should have been retorqued on the left side of this motor.

 

[expatexplorer]

I have the exact same problem you have described. Rough idle and slight coolant loss. Everything else checks out ok so I am assuming that I have a slight gasket leak and burning the coolant through the exhaust but have not determined which cylinder as all plugs look ok. I am not sure what my next step will be just yet other than replacing both head gaskets.

 

[Argentimage]

I have the exact same problem you have described. Rough idle and slight coolant loss. Everything else checks out ok so I am assuming that I have a slight gasket leak and burning the coolant through the exhaust but have not determined which cylinder as all plugs look ok. I am not sure what my next step will be just yet other than replacing both head gaskets.

I know this is old thread - but I always heard from the PT Engineers at FROD that the 4.0L was a cement truck engine subject to poor head gaskets...

and with so many of these out there

- why don't we have any expert advice and reccomendations on coolant consumption???