'91 Grand Prix 3.1 running rough, gasoline smell. misfire?

[Psych0matt]

It's been an amazing reliable car, with 180k I've been driving it every day (with a few exceptions) to work and back (15 miles one way), and I haven't had to put a dime into it aside from a quart of oil because of my next thought. I drove home last monday evening normally, everything was fine. Monday evening I back it out of the driveway because I decided to drive the blazer to my parents house. I noticed it was running rough but I thought maybe it was because I jumped in and started her so quickly just to roll it 30 feet. Tuesday I jump in to drive across town and its running really rough, a little bit of smoke when I take off from sitting at a light, and the smell of gasoline. Now, the smoke didn't appear to look or smell like oil, just unburnt fuel. I grabbed a timing light and checked all my wires and I'm getting at least what appears to be decent spark from all 3 coil packs, because that was my first thought. I need to pull all the plugs, but beyond that I can't think of much until I get a chance to dig in. Anything that would just all the sudden pop up like this and not have any warning signs, but is still drivable but just rough? Any ideas?

[swift13]

with out knowing too much about it....suggest vacuum leak, icm, iac tps...etc...etc (sensors should throw a code tho) check pcv valvle , may have come undone.

[Jonpro03]

I think the fuel pressure regulator gave up. Pull the vacuum line and see if there's any fuel in it.

 

Also, could be a vacuum leak. The line that goes to my trans loves to come undone.

[Psych0matt]

both good thoughts! It's not throwing a code though, forgot to mention that. I'll check on the vac lines and FPR

[AL]

Check the MAP sensor too

[RobertISaar]

check the carbon cannister and it's vacuum lines while you're at it.

[alec_b]

Early 3.1's have a problem of burning up PCM's too. I had a '91 lumina come in that ran just like that, started hard ran super rich, never threw a code. Turned out to be a bad PCM, but there were other symptoms (SES light didn't work, speedo would come and go, etc).

[Psych0matt]

well, Its currently not throwing a code (I;ll check to see that the SES light is functional tomorrow when I tear into it), but the speedo has been off since I got it, at 70mph it shows about 105 I might take it into midas/meineke/"insert favorite auto shop" tomorrow just to get their opinion, since I also have to take the truck in for an alignment