1995 astro problem rough idle

[tysons]

my problem with my van is. it will run rough at idle but only when it's been driven to normal engine temp. example drive to work 20 minutes into the ride, i'll catch a red light and have to stop while waiting a few minutes it'll start missing (the engine) spudering, smell of unburnt gas.
light turns green and with a touch of the gas pedal it's gone until the next light. if tryed a few things like tune up and fuel filter. my auto mechenic thinks i shoud leave it alone b/c it hasn;t let me down yet. he thinks it would cost $$$$$ it start changing parts until the problem is fixed. the only code the engine reads is o2 senor.
anyone have any ideas?

[95silverado]

If the O2 sensor is bad, the engine will run too rich. That would explain the rough idle, and smell of unburned gas. You can take the truck to most auto parts stores, and they will hook it up to a scanner. It should tell you which O2 sensor to replace.

[ytbdej]

Had the same problem with a 90 Astro. Like to pulled my hair out. Tried all of the stuff, O2, fuel filter, tune up. Noticed one day with the hood out and engine running there is a air cond. line one the drivers side that loops over the engine. I cought out of the corner of my eye water dripping. As I watched this the air would kick on and the pipe would have condinsation build up, when the air would kick off the water would drip onto the valve cover run down and drip onto the center spark plug wire boot, this would cause an ark an a miss on that cylinder. I replaced the plug and wire. Went to Lowes and got some pipe insulation tape with metal cover. Taped up the pipe and ever since the van runs like a top.

Originally Posted by tysons

my problem with my van is. it will run rough at idle but only when it's been driven to normal engine temp. example drive to work 20 minutes into the ride, i'll catch a red light and have to stop while waiting a few minutes it'll start missing (the engine) spudering, smell of unburnt gas.
light turns green and with a touch of the gas pedal it's gone until the next light. if tryed a few things like tune up and fuel filter. my auto mechenic thinks i shoud leave it alone b/c it hasn;t let me down yet. he thinks it would cost $$$$$ it start changing parts until the problem is fixed. the only code the engine reads is o2 senor.
anyone have any ideas?

[tysons]

thanks for the reply, i'll check that out. i did a tune up a few months ago, so i don;t think i'll be as lucky. i'll let you know how it goes. it likely is something stupid like that for sure!

[dmmosko61]

Originally Posted by tysons

thanks for the reply, i'll check that out. i did a tune up a few months ago, so i don;t think i'll be as lucky. i'll let you know how it goes. it likely is something stupid like that for sure!

I had a somewhat simial problem, see 2001 Astro van keeps stalling. Not only would our van idle rough at stop lights it would ultimately stall unless I kept my foot on the gas. After much effort to resolve, it was ultimately corrected by replacing the PCM. Not only is my stalling resolved but my idle is noticeably smoother. This is a great bulletin board.

[SMarquez]

I've had to replace the injectors twice. Seems like some kind of design flaw. Cost at mech is a little over $600. I bought one on E-bay for $180 and with a manual was able to do it myself in 90 mins.