I have heard that it is possible for a bad EGR valve to cause some oil consumption. I just wondered if it was true, and if so how? Because, I need to get around to replacing my EGR. (getting code light, and my mechanic said the he we pretty sure the valve was bad) I'm trying to track down a little oil consumption problem on my 89 Bird 305 TBI. Replaced the valve guides (No more smoke on start up or on deceleration) Really, I don't see any smoke period now. But, I am still using a quart every 1000-1500 miles (depending on the cars mood I suppose). This car does not get driven hard as in WOT. I have a 2-hour round trip to work everyday. (99% highway driving). I don't have any visible leaks of any kind that I can tell. Also, I've replaced my PCV valve. Car has about 101,000 miles on it, and it starts and runs as well as any car I've owned. If anyone has any thoughts on the EGR thing, or any ideas on where to look for the oil consumption I'd greatly appreciate the input.

 

well do you have exhaust seals on your valves? i am going threw this rite now. according to the performance shop i dropped my heads off at they are saying that it is no suprise the factory didnt install exhuast seals on the valves. seals seem to be something overlooked most of the time, by peeps trying to get away with it as cheap as possible. I had a smoking problem from the time i started the car to the time i shut it down it still smoked after i turned it off. pretty much the only thing an EGR controls is emmisions, and quite possibly A/F mixture(though the O2 sensor adjusts it) though i know some guys who dont even have an egr valve. no oil burning issues to hear of. do you have any other problems inside the block?

a bad EGR doubt it i had a similar problem on my 1998 ford truck the oil consumption was really bad, a simple solution was brought to my attention "try a different brand of oil and a weight, until you find one that stops it, in the event that doesnt work i have been told to use Lucus oil additives/ oil. hey i went with castrol oil i was using Qauker State. my oil consumption was far worse then what your describing i was down to 1 quart every 900 miles, on synthetics it was 2 quarts per 900 miles, buy switching and using a cheap oil additive(stp) im can go between changes before needing to add anything, but it holds over 6.7quarts of oil too. but keep in mind its only a bandage until you can afford to correct the problem.

 

Only reason I thought the EGR might be part of the problem is that I heard that a bad EGR could cause pretty bad vacuum problems, and I've heard that certain vacuum problems can cause oil consumption problems.

As for the exhaust seals in the valves...I don't know. I'll talk to my mechanic who installed the valve guides to see if he knows.

 

Maybe one of your intake gaskets crapped out somehow and you're leaking oil in through the intake ports. Maybe take a look at your spark plugs.

 

I've had the valve guides replaced recently...along with a minor tune-up (plugs). My mechanic said that the plugs looked fine (no oil) just normal wear. If I had an intake gasket go, would the plugs be oiled up and fouled out?

 

For a motor with over 100,000 miles on a quart every 1500 miles doesn't sound that bad to me. My old motor leaks that much and burns more.

 

Just curious...If I had an intake gasket crap out, would it cause any external leaking? I haven't located anything that looks like a leak yet. The front part of the intake is a little wet looking...but, nothing that looks like a leak really.

 

Any more ideas?

 

ttt

 

It could be leaking in a drip at a time through the intake manifold gasket. A drip here and ther won't foul out plugs but will comsume oil over long driving periods like you described. It would be an internal leak and there is no visual signs that it is going. I had a intake gasket fail on me and I had an internal leak that took me 3 weeks to diagnose. If the front of the intake is wet looking that that could be your problem. Oil could be leaking on the inside as well and getting into your intake ports like I described above.

 

What is the best way to check for an intake leak? Also, could a cracked intake cause this kind of oil consumption problem too?

 

Well it is really hard to test for that and you need to pull th eintake to be sure. You may also have aging piston rings that are allowing blow by. It is hard to narrow down the problem on engines that old with miles on them. There could also be pin size hole in your head gasket.

 

Ok, to add something to this topic. What would make and engine use more oil the longer after an oil change. Example: it goes from about 1000 mi, to 800 mi, to maybe 550 mi that you have to add a quart. All in all, prolly have to add 3 to 4 quarts between changes now. And I'm not getting any exhaust smoke. What gives? Still sound like an intake leak?

 

You should have better luck here.

 

ttt

 

ttt

 

as far as why the oil doesn't last as long the longer you drive can be break down of the oil or getting somethign in the oil that thins it out

generally oil should break down that quick though and make that big od a difference


one of the things it would make me think is blow by caused by bad rings


when you get blow by there is a good chance that you aer getting gas into the oil which will thin it out making it more apt to do this


you might want to smell your oil for a gas smell and hell maybe even a coolant smell just to be safe

 

pull off your oil filler cap and dipstick with the engine running to look for an oil fog being speayed out

my limo drinks oil through the pcv because of bad blow by. also pull the cap rotor and see if its oily up there.