i bought this car in Feb’05 w 45k miles. in less than two years it has 82k. so after a cross country trip, i took it to mechanic because it smelled like it was overheating but never had. diagnosis was leaking seals dripping on the manifold and making the smell. since it was kind of a job to repair i decided to do timing belt and more at the same time even though i had another 30k miles to go. here’s the list: timing belt w idler rollers and tensioner, power steering belt, alt belt, water pump, crank shaft oil seal, cam shaft seals. a week later the ‘check engine’ light came on. testing showed 4 cyl misfire so had plugs and wires. about 100 miles later the light came on again. then in a while went off. has been going on and off for a while always showing the same cyl misfire. one day it started flashing and had 2 codes. the original and also cyl 2 misfiring. had the coil replaced and a leaky valve cover gasket. i was planning to sell the car to keep from going crazy and broke but, alas, today the light came on again. i am going to cry. mechanic said he checked timing twice. other mechanic thinks it should be checked again. there is never any symptom of misfiring…the light just comes on. anyone have any ideas? thanks.
Just to clarify. You’re saying that you’re getting misfire codes and the engine is apparently running fine? No slight hesitation, bucking, surging, slightly rough idle, etc.?
The first thing I think you should do is drop by a local AutoZone, etc. and have them pull the codes. Post any results here. AutoZone will do this for you free.
Also, you have 2 mechanics talking about timing. Are they referrring to cam timing or ignition timing? One would hope it’s the former since the latter is computer controlled and the car does not have a distributor.
the codes are from auto zone. and no there’s no hesitation, bucking or anything. the light just comes on, stays on a while, then goes off. i think that mechanic #2 thinks that since the timing belt itself was changed that the timing is off. oh, and the code is always cyl 4 except that one time when the light started flashing. then it came up both two and four. mechanic #1 (who did all the initial work) said that 2 & 4 are controlled by a different part of the coil than 1 & 3 so it must be the coil (i may not have stated that quite correctly but you get the idea, right?).
wow, i am so sad. i found a site called subaruforester.org and discovered that the first foresters made (mine), had serious engine problems. it seems that it is not a matter of if it will blow it’s head gasket, but when. i may never find the problem that is causing the light to come on. one person said theirs came on the day after they bought it and stayed on for 4 years. at that time it got a cracked block or something. the knock sensor seems to be a common problem, but from what i understand, it would show a code. sounds like the '98 might have been a lemon…anybody? oh the other minor problems were the neutral switch on manuals (mine), and catalytic converter. the only subaru dealer is 80mi. and i really don’t know if it would help to take it to them, although i’m sure they’d find something to fix!!
Often a head gasket leak on these cars is an external one. It may drip coolant and you may smell it but it does not affect the way the engine runs nor will it set a code.
I’m assuming here you have a 302 and a 304 code?
While I realize that most shops or techs may not do this, I believe that every time an engine has a performance problem a compression check should be performed. The spark plugs are out anyway, or should be, and this only takes a few minutes to do. It can halt the parts replacement process of trying to cure a mechanical fault.
A compression test should be used along with several other methods to verify any internal head gasket problem that may be causing this problem. The other methods are a coollng system pressure test, hydrocarbon test, and the use of a vacuum gauge.
Since you have a vehicle that appears to run fine other than setting those codes this could mean the misfire is so slight as to not be noticeable to you.
I’ll throw this out there for consideration. This engine should use mechanical valve lifters which means a certain clearance is required. It’s possible that a valve or two on cylinders 2 and 4 could be tightening up too much.
The less than required clearance (called lash) is too tight even on a cold engine. As the engine warms up metal expands and the clearance will shrink even more. It could be that a valve or two is being held slightly open when the engine is warm and this could cause the problem you have.
IF, this is the case then the valve lash should be inspected and adjusted as necessary as continued operation over the long term can cause cylinder head valve/seat damage; spelled c-o-s-t-l-y.
With a warmed up engine the use of a vacuum gauge could also possibly show if this is the case here.
One other possibility could be a vacuum leak on one side of the intake manifold. Since 2 and 4 are the problem cyls. it is possible to have a vacuum caused misfire on one side of the intake and not the other due to the Subaru intake design. A vacuum gauge will tell the tale.
Sadly, many techs don’t use a vacuum gauge or run compression tests when diagnosing a problem. At this point I would not assume the head gasket is the problem just yet.
(And don’t worry about cracked heads and blocks. The chance of that is near zero and cracked whatevers is a diagnosis that is erroneously tossed around way too much.)
Hope you can glean something out of all of this.
thanks so much. i will print this out and take it to the shop. this is a small town so i don’t know what they use. i may have to take it somwhere else. but i will carry this w me everywhere. thanks again.