I've got a 93 Accord 5spd that I use for work (I deliver pizzas)...it has been giving me some problems lately. It's been sputtering pretty bad at idle (the sputtering is very rhythmic and percussive, like someone's hitting a bass drum in perfect time), and whenever I'm in neutral and hit the brakes, turn the wheel, or use the AC, the RPMs drop considerably to the point where it seems like the engine might die. A couple times on really hot days with the AC going it did actually die, then wouldn't start back up for a few minutes. The only thing that makes it start again is opening the hood and letting it air out for a few minutes, although the temp gauge doesn't indicate any overheating and the thermostat was replaced recently. During acceleration and at cruising speed the car runs smooth as silk. Also, whoever owned the car before me did the timing belt himself and put it on too tight so there's a pretty loud whine...but when I bought it there was a sizable exhaust leak so I couldn't hear the whine over the loud exhaust until I fixed it. Clever bastard...

Anyways...
I took it to a place by my house & they informed me that cylinder 3 wasn't getting any compression...that it was essentially dead, so that's why the car would die because it wasn't getting enough power. Quoted me $800-1000 for the repair. They checked plugs, wires, and the distributor as well, which were all fine. But the curious thing is, every once in a while when I start it up, it'll run perfect...no sputtering, no power loss, nothing (except the whine). This happens most frequently in cooler temperatures. I wouldn't think a dead cylinder would magically turn back on for no reason, so could it possibly be something else, maybe something electrical? Or could the two problems be related, like it's not timed right or something so it's causing the misfire? Also curious is that the check engine light comes on after a couple minutes of driving, but no one has been able to get it to spit out a code.

I would really appreciate your input. If the repair is not very invasive, I'd much rather fix it than sell it. Everything else on the car is great...

Thanks!

 

Is Check Engine Light on steady or Off?

From your description, the Idle Air Control Valve (IACV) is not functioning. This usually means the IACV is totally clogged w/ carbon gunk. Cleaning throttle body bore, throttle plate, and IACV should fix the problem unless there's an electrical fault w/ IACV. If slightly opening throttle w/ foot pedal improves starting, IACV and throttle plate blockage are confirmed.

See IACV Cleaning in DIY forum for guidance and download a manual from the Online Manuals post links in DIY forum. Any manual from 90-93 will be fine for your 93 Accord.


Since car runs smooth under acceleration and other times, you can discount the shop's diagnosis of a dead cylinder. A dead cylinder will produce a strong vibration under acceleration and very poor idle.

good luck

 

Thanks for the advice. Check engine light is off when car is first started, then comes on steady after 1-5 minutes of driving (varies).

 

Sorry, one more tidbit of info--when the shop was diagnosing the car, they pulled the plug wires out of all 4 cylinders one by one. When the wire was removed from cylinder 3, it was sparking, but there was little to no change in the engine. When wires removed from any of the other 3 cylinders, the car died.

 

What was the compression on each cylinder?

It sounds like you have a compression problem. Now it could be from the piston rings, the head gasket, or the intake/exhaust valves. The next step would be a leakdown test.

 

Did they actually measure compression? Or did they just check by pulling the plug wires like you described? If they didn't measure it, then we don't really know - it could be an injector not firing so that one cylinder doesn't get fuel.