I’ve got an 86 Olds Cutlass with only about 66k mi. It doesn’t start (or stay started long) without giving it some gas. This gets worse in the cold. After it gets started and I drive down the road to one of two stop lights, after I start to move again the engine usually wants to die - letting up on gas then back down somewhat heavily helps. When the gas pedal is barely pressed down, it sounds and feels as if the engine is getting less gas rather than more. When I finally turn off the car, there’s sometimes a funny burning smell, not like brakes or tires. Someone mentioned it might be the catalytic converter. I passed my NJ state inspection after getting a new exhaust system. Could this all be related to a problem with the idle? Do I need a new fuel filter or something?
A clogged catalytic converter can cause some of the symptoms you have, but I don’t think that’s the problem just because of this:
This makes me think its more of a fuel type problem. It could be a lot of things, though.
If the fuel filter is clogged, when you step on the gas it’s going to suck in more air, and since the fuel is being restricted it’s going to screw up the air/fuel mixture and cause the engine not to run right.
If the carburator isn’t adjusted right or its clogged you’ll get kinda the same problems since the engine could be starved for fuel. When I had this problem on a VW engine I have though I didn’t get the “feels like its getting less gas” when you press on the accelerator symptom though.
I’m also wondering about the spark advance on the distributer not working right. This might be due to a problem with the distributer or it might be a vacuum leak. A vacuum leak is easy to check for. With the air cleaner off, hold your hand over the carburator intake (you’ll probably want to wear a work glove for this in case it backfires). Slowly lower your hand so that you start choking off the air going into the carburator. If the engine actually starts to run better, it’s because its getting too much air, which means you’ve got a leak in your vacuum lines somewhere.
Does the problem get worse when it’s wet also? I would start looking at the distributer (and its cap) and spark plug wires. This might account for that burning smell too. If your engine is like the 87 monte carlo I used to have, there’s an electronic module inside the distributer that might make a burning smell if it was starting to go south. If the spark was starting to burn through some of your wires instead of going to the spark plugs that would also make a burning smell.
Do any of the belts squeal? I’m wondering if maybe the bearings in something like the alternator or the power steering pump or maybe the air compressor are starting to go, making it hard to turn. This would add a big load to the engine, and the added belt friction might also account for that burning smell.
Your check engine light isn’t on is it? You didn’t mention it, but I thought I should ask.
(disclaimer - I’m just a backyard hack mechanic, someone with more knowledge will surely be along soon with better advice)
Our second car, a 1988 Pontiac Bonneville, had symptoms very much like the ones you describe last winter. No check engine light was on; the sucker just would quit running. It took 3 trips to the mechanic before we tried the last (but of course, most expensive) repair: replace the computer. Haven’t had any trouble since.
No check engine light.
I haven’t noticed whether it’s worse when it wet or not. I’ll keep the distributor in mind.
I get a belt squeal when I turn the wheel all the way over either way; I’ve been told this is due to power steering. Makes sense to me, though I’m not sure if it’s the belt or the pump.
I get a funny noise when the A/C is on and I’m at idle. If I had to guess I’d say it could be the belt making the funny noise. (fyi, this car has many separate drive belts, not one long serpentine belt.) This is after driving for a bit. I obviously never have the A/C on when I start the car or until I’m after the aforementioned stop lights where I sometimes stall.