My car is having running issues...details inside

[34v6needhelp]

Ok, I have a 3.4 firebird. For the past month it has been losing oil pressure at certain RPM's. When it would lose the presure in the RPM band, the motor also would sound kinda funny...kinda flat sounding.

It used to idle at a good oil pressure. Now it idles at a negative oil pressure...has ZERO power, and the motor sounds real funny...and the check guages light is on...

Can anyone tell me what is wrong with my car?

I have checked my oil...and this change has only had 2.5K miles on it.

[hammertime]

How many miles on your car? Have you let the oil get low on more than one occasion? How well have you kept up on oil changes and maintenance?

The oil needs to be present at all times. An engine that is run low on oil can become starved for oil and lose the oil wedge between the crankshaft and bearings. Once that happens, metal contacts metal and wear causes the pressure to drop. From there, its ususally only a matter of time before the pressure is gone.

It probably sounds funny because of the load being placed on it while the friction increases as the bearings start wearing.

If you don't know a good mechanic, I'd stop driving now and find one. But truthfully the damage is done.

[34v6needhelp]

about 100K miles
Oil has never been low
Oil changes every 3K miles

And I had a friend look at the car...I had a coolant flush about 6 months ago...and now it is brown...he said exhaust is getting into the coolant...any truth to this?

Am I looking at a screwed 3.4L?...if so any advise?

[34v6needhelp]

Any more info for me?

[RainMan]

The GM 3.4L along with it's older siblings, the 3.1L & 2.8L are the family of 60* V6 engines. They had a history of internal coolant leaks due to faulty intake gasket/design. Oil & Water don't mix, and engine damage can occur quickly.

My initial instinct would be a faulty oil pressure sending unit, guage, guage cluster, or printed circuit. However the other symptoms you describe indicate a more serious problem.

As Hammertime mentioned below it sounds like your mains are possibly damaged. When that kind of damage occurs the bearing clearances increase and oil pressure drops. Once this happens it just get worse until bearing failure occurs.

Some Examples of Bearing Damage: http://groups.msn.com/MotorLovers/bearingtech.msnw

Few more questions?

How long have you had the car? What kind of history?
When you say the engine sounds funny, funny how? How exactly does it sound? Knocking? Clattering? What?

You mention that your coolant looks brown after 6 months. What type of coolant are using? The typical Green Ethylene Glycol or the Extended Life like Dex-Cool which is Amber in color? Does it look like mud?, or Brown Cottage Cheese?, or more like Rusty water?

What your friend is talking about sounds like excessive blow-by due to a worn out engine with bad rings. All that crap from the cylinders, spent gasses, fuel, carbon. . .all gets down in the oil and eventually can trash the bearings. Does your oil smell like raw gas? How do your Spark Plugs look?

Reading Plugs: http://www.centuryperformance.com/spark2.asp

Have you noticed any coolant in the oil? Oil will look milky almost like chocolate milk.

Other things to consider, oil pump failure, dropped oil pickup, clogged oil passages. . .etc. . .etc

Let us know. . .Good Luck.

[34v6needhelp]

I have had the car for about 6 months...I flushed the coolant and put spark plugs in at this time.

The car sounds like it has an exhaust leak. Kinda clattering I guess

I am using the green coolant. It looks like mud now.

Oil looks fine/smells fine. I have not checked spark plugs.

How do I check for clogged oil passages?

[34v6needhelp]

I should add.

When I would start the car, I would have to crank on it for a while...like maybe 45 seconds...until the oil pressure guage would come up...then it would go ahead and start.

[hammertime]

Do you know the history of the car before the last 6 months? If you bought it used from someone who ran the hell out of it, the may have negelected it, worn it out, and used a heavier weight oil like 20-50 do keep the pressure up and pass it off as a sound running engine. When you start putting 5-30 oil into, there's just not enough oil there to do the job.

Sounds like you are getting some sort of oil or other contamination in the coolant. I think you may have more than one problem, and I doubt either of them will be easy/inexpensive to fix. Find a mechanic - you probably need a rebuild.

[bww3588]

good time for an LSX

[34v6needhelp]

What's an LSX?

[hammertime]

A 5.7L LS1/LS6 or 6.0L LS2 engine out of a later model Camaro, Corvette or GTO.

What most people come to the board to read about.

[34v6needhelp]

O...the "X" is a wild card...yeah now I get it...a LS1 or a LS6...ok

If that isn't something I can do myself is it stillworth paying someone to do it for me?...how much should this cost?

[bww3588]

well the engine/tranny combo will run you around 6k +- then you gotta have the k member, wiring harness......all the other stuff related to swapping it.....so probably somewhere around 10k.