I have a 1991 Honda Civic Dx that I just purchased about a month ago. It has 40k on the motor and tranny and has been running just fine up until last night. I got a full tank of gas yesterday in the afternoon, drove it to work, parked, drove to a friends, parked, and sat it for about a half hour. When we got in the car to go somewhere it started to run really rough. I have an oil leak where the previous owner had an oil pressure gauge hooked up and didn't plug the hose but after I plugged it, it still ran rather rough. It's putting out a gas and oil mixture out of the exhaust and the idle is really rough. I cleaned the IACV and adjusted the tp screw. I could really use some help on this, it's my dd. Please let me know, thanks.

 

Did it run out of oil then? The only way that oil comes out the tailpipe is from a major mechanical problem. A compression test would be a good idea.

 

It wasn't full out of oil. Explain what you mean about the compression test

 

Compression test is where you remove the spark plugs and connect a gauge to the cylinders one at a time to see how much air pressure they can generate when the engine is cranked. (obviously it won't run with no spark plugs, also the ignition system should be disabled to prevent damage to the ignition coil). The pressure result will reveal if there are internal problems with the valves, rings, pistons, etc.

 

Alright, I'll try that. Thanks a lot, I'll let you know what I find out.

 

Cylinder 3 acted like a geyser and was shooting gas out. Changed the fuel injector and checked the wiring and its no longer shooting gas out of the tail pipe or the cylinder. Still runs a little rough, a little studder but it might be the axles or something. If anyone has any input on that please let me know.

 

I guess it was a stuck-open injector. I'd change the oil after you replace the plugs and wires (if they have lots of miles on them).

 

Oil and plugs were changed like 2 weeks ago, but after all the problems that went on I guess it wouldn't hurt. Do you think the shaking could be anything suspension wise though?

 

When there is an injector stuck open, a lot of gas will get into the oil and dilute it's lubricating properties. So change the oil again even if it was new.

Shaking at low rpm and high throttle is usually misfiring due to weak sparks.

 

...not if it shudders while the car is not moving. I have to wonder how the other injectors are doing.