Misfires in 98 Subaru Outback w/ 2.5

I bought a 1991 Honda Civic a little over a year ago when it had 120k miles. At 130k it started knocking and there was no check engine light. It only knocked when given too much throttle for a given engine speed, but never in 1st gear. It definitely related to the load on the engine. I assumed it was an ignition problem, and as part of my troubleshooting I eventually coughed up the money for a timing light. I found my timing to be way off and found the timing belt off by a tooth.

I guess what I am trying to say with this post is that your timing belt could be installed improperly, and you may not even notice serious driveability problems immediately. Since you were able to experience the car with the belt properly installed, can you remember a decrease in performance after you did the seal job?

P.S. - I took the car to a chain mechanic who rode with me around the blocks a few times, and I made it knock for him. I don't know if he could hear it or not, but he said some crap like, "That's what I should expect for a car with that ind of mileage". BS

Mark

Seems that some mechanics are still stuck in the stone age, when it was amazing to get 60k out of a car without serious engine problems or a complete replacement. Honestly, any car made within the last 10-15 years should be capable of over 200k miles, given proper care and maintenence.

-Matt

You must've been buying some rather crappy cars, back then -- if you were buying any cars at all in the "stone age". Perhaps you bought VW Beetles, or early Subarus, or early Toyotas, or a Chevrolet Vega (was there anyone dumb enough to buy two?), or any of many other examples of engineering mediocrity. Either that or you watch too many ads on TV.

Contrary to your implication, automotive durability did not suddenly appear (boom!) in 1990. It didn't even become universal around that time. In 1990, one could buy a Yugo or a Hyundai Excel or a great many other cars wholly incapable of 200K miles even pampered and given heroic maintenance. Guess what? You still can, right now, today! Hey, Subaru didn't fix their piston slap problem in the 2.5 until Y2K when it was redesigned for non-interference. But I digress. Y'ever hear of the slant-6? How 'bout the 318? The 350Y? The 232, the 258, either of two different-make 3.8s, The B16, the B18, the B20, the B30? All of those and many others routinely made it well past 200K miles (before 1990!) with nothing more than normal maintenance, even with yesterday's relatively inferior oils, filters, etc.

It's a common error to believe that the dawn of engineering rectitude coincided roughly with one's own birth, and that "newer" necessarily means "better". Fortunately, there are plenty of counterexamples to this sort of stinkin' thinkin'.

DS

I just had the chance to take the timing belt cover off to verify that the belt is aligned properly w/ the cam pulleys and the crank pulley as well as the marks on the timing belt cover, etc. It looks like everything is lined-up perfectly! I was originally thinking that I could have the belt off a notch or something, but I don't believe that's the case. I've replaced the belt in the past and this looks just like it should.

Has anyone with subaru experience seen this type of problem (Cyl 2&4 misfiring even after replacing coil, wires, etc)? Does anyone w/ Subaru experience have any ideas as to what I might be fighting?

Is there some kind of ignition module or other electronic component in the ignition system that might be causing a misfire in cyl 2 & 4?

A very common cause of persistent misfire is as follows:

Misfire occurs due to secondary voltage leak down spark plug insulator to ground. First component replaced is spark plugs, but plug wire boots have also been affected, so affected plug boots continue to allow voltage leakage. Misfire persists, so spark plug wires are replaced, but plugs are left alone since they were just replaced. But, faulty plug boots caused leakage path on plug insulators. Back and forth and back and forth. Often a persistent misfire of this nature will go away when plugs AND wires are replaced at the same time.

Daniel, that's a great point. This is exactly what I've done. I replace the plugs, THEN the wires and now I've got my problem again (it did seem to work fine for about a thousand miles though). Do you think that since the misfire has started occuring again (maybe due to damaged plugs?) that the new plug wires I recently put in (about 1200 miles ago) might now be damaged and in need of replacement at the same time as some new plugs?

Gilles Gour, Can you expand on the igniter a little bit? I haven't seen it in the Haynes manual. Where is it, what does it do, and how can it be tested/replaced?

Thanks for the input!!!

Yep, that is a distinct possibility. When the spark "leaks" down the side of the insulator, it forms a conductive path on the insulator AND the inside wall of the boot. Fixing half the problem (replacing the plugs OR the wires) will generally reduce the leakage path's severity enough to get you a thousand miles or so of good running, but it's not a long-term fix. Replace the plugs AND the wires. Or, if you feel like trying to save your almost-new components, wipe the plug insulators and swab the plug boots' interiors THOROUGHLY with denatured alcohol (Q-tips work well for the boots) until they are squeaky clean. Apply silicone dielectric grease liberally to the plug boots, and reinstall everything.

Vehicles with distributorless ignition do not use ignitors.

DS

Sorry Daniel, but my 96 Legacy has a distributorless ignition and has an igniter. The igniter is the electronic component that triggers the primary circuit of the ignition coil. On my car - and I think on most if not all Subarus - the ignitor is in the middle of the firewall. The wires going to the coil's primary circuit will lead you there. On page 2-16 of the Chilton's manual in the «Distributorless ignition system», one can read: «The Ecu receives signals from the airflow sensor, water temp sensor, crank angle sensor, cam angle sensor, knock sensor and other verious indicators to judge the operating condition of the engine. It then selects the optimum ignition timing stored in the memory and immediately transmits a primarun current OFF signal TO THE IGNITER to control the ignition timing.» I could give you the testing method for the igniter when I put my hand on my Haynes manual. Chilton's does'nt give any.

Hmmmm My 98 Impreza outback is distributerless and it sure as heck does have an igniter.

The igniter is on the firewall, just below the rubber hood insulator.

I stand (sit) corrected!

Gilles Gour wrote in news:UvXId.2459$ snipped-for-privacy@wagner.videotron.net:

The '99 Toyota Tercel and other newer Toyotas also have igniters. The igniter in those cars is in the same housing as the coil, on top of the spark plugs.

I did look through the Haynes manual again and it said to test the igniter, I would need to connect a LED light between the battery and two outside conductors on the harness connecting to the coilpack. I went outside and confirmed that there is an igniter present. Now I'll try to find an LED testlight to test the igniter if Daniel's suggestion of replacing these two spark plugs and cleaning up the cables and using the grease does not fix the problem.

In relation to the fuel related suggestions earlier, I kind of doubt that there's something wrong w/ the fuel rail on the drivers side of the engine, because the fuel path coming out of the tank is through the filter, through the rail feeding the two problematic cyls on the driver's side (2 & 4), and then over to the rail that feeds 1 & 3. I would think that if there was a blockage of sorts, it would affect Cyls

1 & 3 more since they're farther downline. I could, however, make a case for the injectors on 2 & 4 being clogged sooner than 1 & 3 if debris happened to make it past the filter.

Just > The igniter is on the firewall, just below the rubber hood insulator. >

long-term fix.

haven't seen