94 Gs300, Running Rough

[peterdfowler]

101k on drive train. Changed all belts (including timing), plugs wires and hoses at 80k. Has a valve cover leak. diagnosed to be the 4th cylinder. Codes show both a lean and rich condition, not sure what the actual codes are. Runs rough all the time, some times more than others. Is it possible to be the injector? and if not what? Thank You In Advance:) Pete

[TigerFish]

101k on drive train. Changed all belts (including timing), plugs wires and hoses at 80k. Has a valve cover leak. diagnosed to be the 4th cylinder. Codes show both a lean and rich condition, not sure what the actual codes are. Runs rough all the time, some times more than others. Is it possible to be the injector? and if not what? Thank You In Advance:) Pete

Was it running rough before changing the belts/leads/hoses? Or just since? What hoses did you change? Where abouts is the valve cover leak?

[peterdfowler]

101k on drive train. Changed all belts (including timing), plugs wires and hoses at 80k. Has a valve cover leak. diagnosed to be the 4th cylinder. Codes show both a lean and rich condition, not sure what the actual codes are. Runs rough all the time, some times more than others. Is it possible to be the injector? and if not what? Thank You In Advance:) Pete

Was it running rough before changing the belts/leads/hoses? Or just since? What hoses did you change? Where abouts is the valve cover leak?

The car just started running rough a month ago (3/29). The work described was done 2 years ago and only changed the front hoses. The valve cover leak is in the rear and is on the drivers side (near the #4). My machanic thinks it's a fouled plug, but I conviced him that that wouldn't give a lean condition, he agreed.

He also said that when he stopped spark to all but the #4 cylinder it ran rougher. When stopping spark to the #4 it ran the same. The check engine light is not lit all the time and comes on and goea off periodically.

[TigerFish]

From what you have said, I would say a fouled plug Or something along the spark route to #4. Dizzy cap, lead, cap, plug. If it was an injector, you would expect some difference in engine note if you stopped the spark to #4 unless the injector had completely failed. No idea what codes can be reported, so don't know if it would bring up a fault code on an injector to pin point one. When I got water down the plug wells when I had to change the heater valve, that caused a similar problem which I thought would dry out. It didn't so I had to take it out and clear it all up and then everything was hunky dorey. Could be equally as simple for your problem.

[peterdfowler]

It was in the end a valve cover leak causing my plug to foul. Woohooo 150 parts and 120 labor, it now runs like the lion of old:)

From what you have said, I would say a fouled plug Or something along the spark route to #4. Dizzy cap, lead, cap, plug. If it was an injector, you would expect some difference in engine note if you stopped the spark to #4 unless the injector had completely failed. No idea what codes can be reported, so don't know if it would bring up a fault code on an injector to pin point one. When I got water down the plug wells when I had to change the heater valve, that caused a similar problem which I thought would dry out. It didn't so I had to take it out and clear it all up and then everything was hunky dorey. Could be equally as simple for your problem.