Jessesdavis1982

2005 Cammed, headers, intake, tuned for 93 octane

I bought the car modified with 71k it now has 90k. I noticed oil consumption about 6 months ago. Around 2k miles it'll be a quart low and the first time I realized it was using oil the stick was bone dry.

It does blow blue smoke out of the tailpipes. The inside of the tip of the pipes are black from exhaust. The left side of the engine has a oil residue around the top of the spark plugs.

Is this rings, something else or a combination?

Thanks

Mr. D

I'm an "old iron" hot rodder, so I'm not too knowledgable on newer engines, but here goes.

High oil consumption is usually a simple leak, leaking valve seals, or worn piston rings. If no leaks on ground or oil on undercarriage from a leak that blows oil only when driving, then I would look for bad valve oil seals & bad rings. I would do a compression test. If cylinders are all showing good/even compression, then my guess would be valve seals letting oil leak into cylinders which is my bet based on your oily spark plugs.

Good Luck,

algregory

I've been using "Tufoil" for nearly 20 years. I had a BMW built for road racing at 132k and the builder recommended it, I sold it at 269k and it was doing very well after 30 sets of tires. My GMC has 238k and is excellent, the GT 73k, and my Yamaha FJR1300ABS some 30k. I use Tufoil and Amsoil in them all. You didn't mention Dino or Synthetic oil.

Will using Tufoil help with an engine that burns oil?
Many old engines show signs of oil burning. Tufoil can help in some cases by freeing up partially sticking piston rings. There have been some dramatic improvements reported from the field where Tufoil freed up the rings and they started working properly again. However If the rings are cemented solid in their grooves or the cylinder is scored, no lubricant can eliminate the smoking.

Jessesdavis1982

I use Mobil 1 synthetic

WJBertrand

When does it blow smoke? If it does it on start up from cold or after sitting a while, it's likely valve guide seals. If it smokes while driving upon letting up on the gas pedal, i.e. transitioning from cruising or accelerating to deceleration, it's probably rings.

Dino Dino Bambino

Blue tailpipe smoke when you suddenly let off the throttle is a sure sign that intake port vacuum is pulling oil from the crankcase past worn valve stem oil seals or worn valve guides. Worn rings usually cause more blue smoke when the engine's under load as the pressure inside the crankcase is increased.
A dry compression test followed by a "wet" compression test on all cylinders should help you make the diagnosis.

jz78817

a leakdown test is a more reliable way to determine if you have worn cylinders. n.b. it's usually not the rings which wear out; they're much harder than the surface of the bore. What most people think is "worn rings" is usually cylinder taper. I had an F-250 with the old Navistar diesel; it still had spec compression (420 psi in each cylinder) but the cylinders were so tapered it guzzled a quart of oil a week.

Jessesdavis1982

Everyone that's replying about it blowing blue smoke, please note that around the top of the spark plugs, still in the engine just pop the hood and you'll see it, there's old oil gunk as if oil has sprayed through the plug. Is this possible?

Dino Dino Bambino

Yes. If enough oil is making its way into the cylinders, any remaining unburnt oil can also find its way up the spark hole threads.
I wouldn't expect a 90k mile old engine to be burning oil but it's possible if the previous owner ran the **** out of it (as it seems likely).

jz78817

on a 3V engine I'd expect oil in the plug wells to be evidence of a leaking valve cover gasket.