Bent crank, delerership taking me for a ride?

[sswloski]

Hello

 

I have a feeling the dealership is taking me for a ride

I'm not a mechanic and am lacking knowledge and technical terms, but I believe the problem is well described below.

 

My 1995 Legacy LS wagon (253,000 km) began inconsistently misfiring a few months back. At first it was only on the highway so I didn't feel the car jerk but did see the check engine light flash. My mechanic couldn't pinpoint he cause so had me continue to drive, asking me to bring her back if the problem got any worse. Over a few months, she began to misfire somewhat more consistently and now at city street speeds (at this speed I could feel the car jerk), so I brought her back to my mechanic who still couldn't pinpoint the cause and so sent me to the dealership. After a 1600$ repair bill where they worked on this and an issue I had where she was sluggish for 5-10 min of driving from a cold start, the dealership informed me that the Crank Pulley is bent, dowel pin for crank is worn and crankshaft is getting worn due to the dowel pin. While the sluggish behaviour from a cold start seems resolved, she's still misfiring. At this point it's back to being less consistent, most of the time at highway speeds but occasionally at street speeds. I brought her back to the dealership and they promptly told me that it's because of the bent crank. They went on to say that this was a diagnosis they could only make once they were working on car and disassembled the components to some level. With the engine running I can see a slight wobble in the lower wheel that the timing belt passes around (sorry for the non technical terms).

The misfire codes Subaru recorded were P0304 & P0303. same error codes persist after the work they performed.

 

Is the bent crank somethign that should have advised me to before any work was done or are they now trying to cover their asses from an oversight on their part?

[GeneralDisorder]

There's no way. They are feeding you a line.

 

The crank pulley, sprocket, and keyway may be messed up but that's easily fixed by welding the key in place at it's proper location then torqueing the components down properly.

 

They all have some wobble to the crank pulley. It's just how they are typically. The rubber in them doesn't last forever and may be thicker or thinner in some areas leading to the illusion that it's wobbling. Doesn't really matter as long as it runs and doesn't throw the belts off.

 

GD

[Ricearu]

that is definately a line.

 

now on the problem, have you replaced your ignition coil? it could be failing with heat, so a cold test could not show a problem. the p0303 is cyl 3 misfire, and p0304 is cyl 4 misfire, and they are both driven by the same pole on the coil. You could also have junk wires on it. Dealer spark plug wires are WAY better than aftermarkets, although I have had good luck with NGK wires, there is no way in gods green earth I would buy house brand wires. Check at night, open the hood, and look for blue "sparks" jumping from either of the rear two spark plug cables with the engine running. Watch out for belts and such. :cool:

WITH ENGINE OFF, You can also pull one rear spark plug wire off at a time and check it for dark spots or abrasions. A dark spot around a pinhole is from carbon building up every time the spark "jumps" to somewhere on the engine.

[johnceggleston]

my experience with 95 legos with wobbling crank pulleys, it will only get worse and then fail all together. as the bolt loosens and the key, key way, and sprocket wear, the timing starts ot change and can cause a mis fire. and eventually the engine will quit. not no internal engine damage so no worries there.

 

so you need to re-do the timing (and probably the belt, idlers, and water pump depending on how old they are) and replace any worn parts on the crank, like the sprocket, key, bolt and pulley. a decent mechanic should be able to do it with the correct info, like what to look for, what to replace and how to put it back together correctly.

NOT the ARROWS, NEVER the ARROWS.

 

but the 3 -4 mis fire does make me suspect the coil. but i would have thought a dealer would have checked for that. the coil has 2 halves, the front half fires 1 & 2, and the rear fires 3 & 4. so a 3-4 mis fire could be a bad rear half of the coil. it may not be the coil but it could be. the symptoms fit. and if there were no other symptoms, that would be my first guess.

Edited July 24, 2012 by johnceggleston

[sswloski]

The dealership replaced the ignition coil, spark plugs and spark plug wires as part of their 'fix'. The plugs and related wires I though were a little suspicious as they were replaced about a year ago by my regular mechanic with NGK products. But the dealership claimed that as they weren't the manufacturer original parts they were causing issues.

 

 

that is definately a line.

 

now on the problem, have you replaced your ignition coil? it could be failing with heat, so a cold test could not show a problem. the p0303 is cyl 3 misfire, and p0304 is cyl 4 misfire, and they are both driven by the same pole on the coil. You could also have junk wires on it. Dealer spark plug wires are WAY better than aftermarkets, although I have had good luck with NGK wires, there is no way in gods green earth I would buy house brand wires. Check at night, open the hood, and look for blue "sparks" jumping from either of the rear two spark plug cables with the engine running. Watch out for belts and such. :cool:

WITH ENGINE OFF, You can also pull one rear spark plug wire off at a time and check it for dark spots or abrasions. A dark spot around a pinhole is from carbon building up every time the spark "jumps" to somewhere on the engine.

[sswloski]

Thanx for your reply

The coil was replaced by the dealer

 

my experience with 95 legos with wobbling crank pulleys, it will only get worse and then fail all together. as the bolt loosens and the key, key way, and sprocket wear, the timing starts ot change and can cause a mis fire. and eventually the engine will quit. not no internal engine damage so no worries there.

 

so you need to re-do the timing (and probably the belt, idlers, and water pump depending on how old they are) and replace any worn parts on the crank, like the sprocket, key, bolt and pulley. a decent mechanic should be able to do it with the correct info, like what to look for, what to replace and how to put it back together correctly.

NOT the ARROWS, NEVER the ARROWS.

 

but the 3 -4 mis fire does make me suspect the coil. but i would have thought a dealer would have checked for that. the coil has 2 halves, the front half fires 1 & 2, and the rear fires 3 & 4. so a 3-4 mis fire could be a bad rear half of the coil. it may not be the coil but it could be. the symptoms fit. and if there were no other symptoms, that would be my first guess.

[Fairtax4me]

They're just not doing a good job of explaining the issue.

A wobbly crankshaft pulley is a pretty common problem, and it could mean that the timing is off. Being off by a small amount will cause inconsistencies in the cam and crankshaft position sensor signals, which the ECU reads to determine fuel and spark timing.

 

That's one possibility. Another is that it could just be a bad knock sensor or temp sensor. Temp sensor is usually pretty obvious if you look at the readout on a diagnostic scanner, but the knock sensor can be bad and cause all sorts of trouble and a scanner might not show that.

 

Timing is fairly easy to check, just have to remove the belt covers. The knock sensor is easy to check with a simple visual inspection. You have to remove it from the engine to get a good look at it but that only takes a minute.

Check out my knock sensor 101 thread for the nitty gritty on inspecting/ replacing that. You can get new ones on eBay cheap that work just fine.

[presslab]

Is your problem all the time, just sometimes, or only for a second?

 

It sounds like an electrical problem to me. I'd start by cleaning the big engine harness plugs and the throttle position sensor. You may have a bad ignitor as well.

[sswloski]

It's an intermittent problem. The most common time for it to occur is when on the highway. It's just as likely to happen when accelerating, as when decelerating or running steady on cruise control. In a 3h drive it'll generally happen 4-6 times, but the timing between seeing the check engine light flash seems random. It can happen anywhere from a few times an hour to not at all for well over an hour. When it does misfire (once or a few times), it can happen anywhere in the beginning, middle or end of the drive.

 

 

 

Is your problem all the time, just sometimes, or only for a second?

 

It sounds like an electrical problem to me. I'd start by cleaning the big engine harness plugs and the throttle position sensor. You may have a bad ignitor as well.

[presslab]

It's an intermittent problem.

 

If it were a constant problem, I could possibly believe that it was something to do with the crank and the engine cam/ignition timing. But being intermittent it would be unlikely for the timing to be just fine one second, bad the next, and then back to fine if it were a mechanical problem. It sounds like an electrical problem.

 

Does it happen worse when the engine is cold? Hot? Cold outside? Hot outside? On bumpy roads? Any pattern you can think of?

[johnceggleston]

another possibility is the igniter. it feeds the ciol in halves as well. so if part of it were bad, and they can be, it could cause a 3-4 miss.

[presslab]

another possibility is the igniter. it feeds the ciol in halves as well. so if part of it were bad, and they can be, it could cause a 3-4 miss.

 

Yes, I agree. :-p

 

You may have a bad ignitor as well.

[Ricearu]

what kind of spark plugs are in it? subaru engines also HATE bosch platinums. they are junk.

 

grab a junkyard ignitor and try that first. they rarely RARELY fail, so likelyhood of a junkyard one working is really high.

[sswloski]

Unfortunately it's not shown a pattern I can recognize.

It's most likely to occur on the highway, but has shown its self at city street seeds as well. While in the highway, it can show when acceleration, decelerating or running steady with cruise control. When it does happen, it can be several misfires in a short period of time, a isolated incident or nothing for well over an hour of travel

 

 

 

 

If it were a constant problem, I could possibly believe that it was something to do with the crank and the engine cam/ignition timing. But being intermittent it would be unlikely for the timing to be just fine one second, bad the next, and then back to fine if it were a mechanical problem. It sounds like an electrical problem.

 

Does it happen worse when the engine is cold? Hot? Cold outside? Hot outside? On bumpy roads? Any pattern you can think of?

[jarl]

I'm sorry if I'm misreading something. You are saying you paid these people $1600, and they returned the car essentially in the same shape as before? For that kind of money you could almost buy a remanufactured engine with a warranty...

 

What do the receipt says they did?

[sswloski]

They fixed another issue, but the misfire (the reason I brought the car in) is still happening. When the problem re-surfaced, I brought the car to my regular mechanics who read the codes to find the same two misfire codes present.

 

I can send you a copy of the invoice if you like (but some of it is in French)

 

Sasha

 

I'm sorry if I'm misreading something. You are saying you paid these people $1600, and they returned the car essentially in the same shape as before? For that kind of money you could almost buy a remanufactured engine with a warranty...

 

What do the receipt says they did?

[jarl]

Français? Pas de problème

 

Even if the pulley driving the accessories is wobbly, it doesn't mean the timing pulley is wobbly as well. If they argued to have fixed the problem -and charged you doing so- they should at least try to diagnose it. They have the means to measure all the parameters being fed to the ECU, if that's what they say is the problem.

 

Can you borrow an igniter from someone/somewhere to see if that cures the problem?

[ivans imports]

all mising the very first step comp test then start to diagnose problems if comp is low will never run good my gess plugs and wires or burt valve or low comp

[Mugs]

It's an intermittent problem. The most common time for it to occur is when on the highway. It's just as likely to happen when accelerating, as when decelerating or running steady on cruise control. In a 3h drive it'll generally happen 4-6 times, but the timing between seeing the check engine light flash seems random. It can happen anywhere from a few times an hour to not at all for well over an hour. When it does misfire (once or a few times), it can happen anywhere in the beginning, middle or end of the drive.

 

 

What you are describing is exactly what my 96 lego wagon was doing. I pulled the timing covers off to see if something was going on in there, and found that my (as described by other posters in this thread) keyway was worn and hogged out my crank and crank gear. So it was "in time" sometime and then would shift out of "time" as well. My crank key slot was so toast that I would have had to split the case and take the crank and have a machinist fix it or just put in a new crank. I bought a used engine from the wrecking yard for 500 bucks, threw a timing belt kit at and called it a day. That was 6 years and about 80k ago...haven't had a problem since.