Chronic misfire and 420 code - what does the future hold?

[Green96GT]

First things first: '96 GT Wagon, 201,000 miles.

 

About 10K ago, one of the timing belt pulleys self-destructed. Since then, the car runs a bit rough and shakes noticeably when at idle. A competent Subaru garage told me that there was most likely damage to a valve(s) when the pulley went, and that there's nothing I can do short of taking the heads off, valve job, etc. It's not the kind of thing I'm willing to tackle, or pay for (it's a beater). I was told that the car could continue to run indefinitely with the valve issue if I could put up with the shaking.

 

Last month I started getting a flashing CEL, and the code was P0420. The flashing comes and goes. I get it when the car is idling, or running at low RPMs, and it usually stops when the car gets up to around 40 or so.

 

I've read the threads about that code: check exhaust leaks, use the non-fouler trick on the O2 sensor, etc. I'm going to try those.

 

My questions: Was the P0420 caused by the misfire (i.e., incomplete ignition, and more bad stuff going through the cat)?

 

Will the misfire eventually clog the cat, or am I OK if I can get rid of the CEL with the sensor trick?

 

Any other longer-term issues that I need to worry about with the misfire? I'd like to keep the car for another 25K or so, at least.

 

Recently (starting before the CEL went on) I've been having a really hard time with cold starts (after sitting overnight at below 20 deg. or so). Any thoughts?

 

Thanks!!!

 

Jim

[GeneralDisorder]

Yes - the P0420 code is being caused by extra unburned fuel going into the cats - you have burned them out and now they are no longer functioning correctly.

 

You can install the non-fouler to eliminate the code.

 

You should rebuild the heads or replace the engine with a 2.2. Letting it run like that is only inviting more problems.

 

GD

[Green96GT]

Yeah, the mechanic replaced all of the pulleys and the belt. I can't recall how much it cost, but a replacement engine was going to be much more expensive, so I took the cheaper way out. Again, the car had lots of miles at that point anyway, so I figured I'd roll the dice. I wasn't advised about the impact of that choice - I should have asked you guys

 

Luckily, there's no emissions testing where I live, so there's no issue about that.

 

You mentioned "long trips." Is there a particular risk that I am facing because of the particular problems I described? The rest of the car is in pretty good shape. I'm planning to give it to my girlfriend to run until it's dead, and it would be good to know what she's up against. I don't want to ruin the relationship

 

 

Thanks again!!!

[Rooster2]

I'm planning to give it to my girlfriend to run until it's dead, and it would be good to know what she's up against. I don't want to ruin the relationship

 

 

Thanks again!!!

 

I don't think giving the car to your girlfriend is the best of ideas. Guys don't necessarily care, but don't like a car to break down. Women are much more concerned about getting stuck with a car that breaks down. If fact they live in fear that a car may break down. Just my 2 cents worth.

[Green96GT]

Relationship advice on USMB - who would have thought .

 

Yeah, I agree. She's a pretty self-sufficient country girl, but after full disclosure, she has declined the offer.

 

I'll keep the car for a little bit longer, then it'll be an organ donor.

[Gloyale]

 

Unfortunately any EJ engine built after 1996 is an interference engine and is pretty much garbage once the timing goes unexpectedly. Best bet is EJ22 swap, and make sure the timing is done on this one.

 

.

 

Actually, it wasn't until late 97 that the 2.2 became interference.

 

All EJ18's are non-interference.

 

And I've seen 2 cases personally on SOHC 2.5s where the belt slips 3 or 4 teeth,(siezed pulley) without any valve damage.

 

They aren't always garbage after lossing a belt.

 

But for this poster, with a DOHC, he definately has bent valves. If you can I.D. which side it is, you can service one head and reinstall for 500-800 bucks.

 

Heck, I've got a few heads I could sell cheap. PM me.