97 Outback weirdness

[Buddythedog]

please help me I love my Outback. that said, It has 120K miles and has had a tune up, plugs, wires, filters, et al. It runs poorly, hesitates, only getting 20 mpg with a 5 speed. I pulled the plugs and found the #2 plug has a grey burnt looking mark on the ceramic (yes, they're platinum plugs) and a matching mark inside the spark plug boot. Yea, thought I. The mechanic also said that the compression for the #2 cyl was 70. He tested #1 and it was 125. He left the plug wire on the #3 cylinder, as he couldn't get it off. Would that affect the compression test? He could only get 3 of the 4 plugs out. I plan on replacing the bad plug and all the wires. The remaining plugs only have 10K miles on them, and ain't cheap. Any advice for me? Don't want to pay for a 2K valve job HAPPY HANUKKAH & X-MAS!!!!!!!!:santa:

 

UPDATE:::::: CRAP. The hideous bile colored glow of the dreaded CHECK ENGINE light is once again illuminating my dashboard. Why oh Why does is still say Cyl 4 misfire? The compression was fine, I checked it myself, the dealer mechanic lied to me to make a couple of grand. I replaced the bad plug. Car runs smoother, but after a day (40 miles) of driving, it came on again. The car does still run rough at idle, but otherwise fine except for bad gas mileage. What do I do? Check the coil pack? :banghead:

[gotsubarus]

good chance its the head gasket.... as most of the 97's develope head gasket problems at about 75k and up . Thay have an upgraded replacment headgasket at the dealer ship.

[Ranger83]

Sir, if you have a 97-99 OB on this board, and it pulls to the right, barks at the moon, rides rough, or your girlfriend doesn't like it, someone on this board will suggest you have a bad headgasket.

 

Between friends and I we have 8 97 or 98 OB wagons, mileage from 60K+ to 180K+, and none have had any head gasket problems. I always hat to say this because I feel like tomorrow it will happen to me, but that's the fact.

 

Some do. But there are lots of reasons for low compression in a cylinder. It is never good news.

 

Most mechanics would put a little oil in the cylinder and do a "wet" test to see right off if it was the rings. Or do a leakdown test t osee if it is valves. And they can do an oil and/or coolant test to see if any contamination present indicates a head gasket problem.

 

The problem with the spark plug may well be unrelated. Yes, having one plug in would affect the comprssion test, but would likely do so uniformly for all other cylinders.

[gbhrps]

The gentleman in the last post has a very good point. My 97 OBW had 122 000 km when I traded it on an 02 OBW, and had no head gasket problem when traded. And why would you give creedance to a so called mechanic who couldn't get the spark plug wire off the spark plug, but is more than willing to give you a tale of gloom and doom! You need to take your car to someone who KNOWS Subarus inside and out before you get ready to shoot your ride.

[99obw]

I have to agree, I would take it to a new mechanic and start over. Based on his apperent level of expertise I wouldn't trust anything he did very much. Make sure the compression test is done at WOT, those numbers sound very low. It's doubtful that a Phase I head gasket failure would drop the compression that much, if any. Could be valves, the wet/dry oil test could be informative.

[alias20035]

A few Phase I's seem to never blow head gaskets, but all of my friend's with the Phase I have had head gaskets let go between 80,000 and 180,000 km. We are all in Canada, where the harsh winters put an enormous amount of stress on the head gaskets. Starting an engine at -30 C is really hard on all engine components, especially the cooling and lubrication system.

 

Given the low cylinder compression I would guess the following:

 

* pressure test not properly done (125 is way too low for a good cylinder, I usually get 180-200)

* badly blown head gasket (should be easy to spot bubbles in the coolant, exhaust gas in coolant, overheating and the other common head gasket symptoms though)

* badly worn or broken piston rings (but 70 PSI is really low for just bad rings)

* bad valve (I have seen one phase I missing 3/4 of one exhaust valve, the compression pressure was under 50 PSI).

* hole in the piston (seen this on non-turbo Subaru's that have been turbocharged)

* if you have a head gasket failure and coolant gets into the cylinder it will essentially clean the cylinder and rings and you will loose the pressure seal, sometimes this leads to excessive ring/cylinder wear and new rings are required to compensate.

 

I would do a cooling system test and test the coolant for hydrocarbons. If the pressure is really 70psi due to a bad head gasket, a pressure test and hydrocarbon test SHOULD confirm it.

 

If the cooling system pressure and hydrocarbon test are unrevealing, I would have the compression test reperformed, and repeated with oil in the cylinder to check for bad rings, as others have noted.

 

If the pressure still comes up low, regardless of what the problem is the head will have to come off. So it would be safe to say that the head gasket has failed even though it may not have, since in any case removing the head will require the installation of a new gasket.

 

Your spark plug wire is probably stuck because oil has gotten into the spark plug hole in the head and degraded the rubber spark plug boot causing it to glue itself in place. Sometimes the boot/wire has to be cut out. You likely need new valve cover seals (its not the cause of your main problem though, just another thing to change).

 

BTW: I just came across my first internally blown phase II head gasket, but it looks like it had the common external left side coolant leak first, lost a lot of coolant and blew the right gasket. The right head is warped, and possibly beyond repair. Owner was panicked until he realised that Subaru's engine warranty is 5yrs/100,000km unlike the big three.

[gotsubarus]

I agree with everyone in here! There have been alot of people that have gotten alot of miles on there 96 and 97 and havent had a problem. But they wouldnt make an upgraded headgasket at Subaru if there wasnt a problem with these year models. Hey out of all the ones i own i only had to do one set of head gaskets on my mothers 97GT and will be doing headgaskets next week on one i sold to a guy last year.

 

I wasnt saying it was a head gasket but it cant be ruled out. It could be a bad spark plug wire or a crank or cam sensor going bad. I have replaced all three at one time or another to fix some cars that run bad. A few of my buddies have had to fix some heads do to running them to long with bad headgaskets or otherwise. These are just some of the things that i have run across... But i agree with getting someone else to do a compression test or buy the guage and do it yourself when changing the plugs and wires.

 

Thats what i do on mine and my dads cars. I guess when you have 2 foresters, 3 GT's, and 2 outbacks, and 6 legacy's, and 4 SVX's, and an XT6, and 1 GL..... and sold 5 outbacks and 3 imprezas and 8 legacy's, 1 loyal, and 1 SVX, and parted out 12 others this year... well ive had my share of problems with these things......

[bustah1]

I've got a 98 with similar problems. Details: 112k miles, no problems. Recent preventive maintenance tune-up changed plugs, wires, etc.

 

CEL came on with Cyl 4 misfire. Mechanic changed plugs & wires again, tested coil & compression. CEL came on again. Mechanic changed O2 sensor and injector. CEL came on again. Mechanic gave up!

 

I took it to Subaru dealer for diagnosis. They say most likely "floating valves" and bad valve seal and estimate at least $2500 for them to take it apart and reassemble and another $900 for valve job. That's IF nothing else is wrong.

 

HELP!!! Anyone have a solution to this problem (other than the $3500 solution)?