auto_editor

Well, she's hit the 170,000 miles mark with her engine and transmission never needing any attention, but that lower-end banging thing (and all of the other signs I've mentioned in earlier posts) points to the fact that my luck is going to change.

Until then--seeing as I'd have to completely re-do or replace her 307 I might as well keep nursing it along for as long as I can--there is really only one (I think) issue that's REALLY worrying me: hesitation.

I can drive around town no problem, but after something like five minutes of steady expressway-style driving (even under 45 mph) as soon as I come to a stop her engine starts stumbling, the oil light flickers, and she seems dead-set on stalling.

Start rolling again and the light goes out but the gas pedal feels like it's got a towel under it and throttle response is jerky at best. But after you've putt-putted along for a couple blocks, everything just goes back to golden again on its own.

Is it overheating? Is it a carb problem? Is it yet another sign that I need to keep my AAA membership current because my "borrowed" time is about up? I need to know!

I'm already not taking the freeway anywhere and driving her at a pace even Miss Daisy would call too slow. I've had the coolant replaced and am changing the oil every 1k miles or so in the hopes that I can eke a few more weeks (or more!) out of her. And apart from this hesitation issue, it seems to be working.

If that's "just what happens before the big kablooey" I guess that's terrible but understandable. It's the NOT KNOWING part that's getting to me.

So thanks, as usual, in advance...

GTI_Guru

with 170K on an original engine, I would check your timing chain. Easily done with rocking the crank back and forth with the distributor cap off to see how much play there is. Those engines have a nylon covered top gear (noise reduction) and when they start coming apart, the pieces can clog the oil pickup screen in addition to causing funny/strange performance issues.

Here's a detailed link to check it yourself

http://www.misterfixit.com/chanslop.htm

If that's all good, then it's possibly an ignition or carburation issue. Usually, you'll get a lot more noise or oil pressure issue (idiot light on at all times at idle) if there's something wrong with a bottom end. With proper maintenance and easy driving habits, there's no reason a bottom end can't go well over 200K miles. The nylon timing gear is usually the weak link. I've spun several of those off older V8's over the years.

-Jeff

johnstonad

I checked the link GTI_Guru. And it is really detailed one. I've learned to fix the issue for it. Thanks.

Destructor

At some point GM stopped using nylon, at least Chevy did. When I replaced the intake gasket on my 88 Caprice's 305 I was able to see the top gear from the valley (through an oil hole) it was all steel, though it is still a good idea to check the chain. I sold the car to a friend and I know he took it to over 150 K. It would be interesting to see if it is nylon or when GM switched to steel.