5.0_faithful

MY car has been bucking and near Stalling when I start it up after I drive it a couple minutes. When I accelerate from a stop the car bucks pretty hard so I back off then it lets up. When I'm at a stop the idle wants to drop down real low like 600 rpm's or 550 rpm's. It feels like its gonna die out but if I give it a little gas when I start to drive again it bucks again. It repeats this for 5minutes or so until The car is at normal temps, then it seems to dissappear. Its been raining here for almost 2 weeks and not sure if this is a possible cause. I need help to figure out whats wrong I need to fix because I'm selling my car and dont want to pass on problems to someone else. THANKS>

90GTRagtop

The way you describe it going away after it warms up makes me wonder if moisture is getting into the distributer cap. Also, check all if the normal idle stuff (Vacuum leaks, MAF Cleaning, IAC, Clean the Throttle Body, etc.)

creepshow

I dunno for sure, but check the tube from intake to mass air and see if it's cracked??

5.0_faithful

My car is speed density so no MAF. I cleaned the IAC, Throttle body,etc.. My tps is .985. Can I take off the cap and just look in it to see if moisture is in there? I'm not sure how to check for vacuum leaks, any info would help. This is only my second Mustang and my first 5.0 so I still have a lot to learn about troubleshooting .

P Zero

Sounds like you need new ignition wires...... just a tuneup in general. Cap,rotor,wires plugs. Easy way to check for the wires is, at night mist your wires with water, if theyre arcing youll see it. Id say do a tuneup it should take care of all of your problems.
-P.

5.0_faithful

At first I thought it might be a timing issue, but when I adjusted timing to 11*, 12* and 13* it did the same thing so when I put it back to 10* where it was originally it still did the same thing so I figured that wasnt the problem.I was using 89 for the timing adjustments, with some octane booster/ fuel injection cleaner. So does it sound like a tune-up to every one else? My cap, rotor, plugs and wires only have 9000 miles on them . I used Motorcraft parts. My oxygen sensors have 10,000 miles of use on them. And if so how often do wires,plugs, cap, and rotor , need to be replaced in general?

90GTRagtop

Yes you can look into the cap, but it can have moisture that's not visible. Couple of ways to check for vacuum leak. One is to use a vacuum guage. Another is to spray throttle body cleaner or starting fluid around spots where leaks could be with the engine running and listen for RPM changes. Look in your cap and on your button for signs of corrosion as well. Like others said, a general tune up could be a good idea.

hollywoodstang89

There is a product called "Wire Dry", made just for this. You can find it at any Advanced, or Pep Boys. Spray it in the cap, and it should get rid of any moisture. I used it once, and it worked. I left the cap to air out, just to be safe, but it worked. Hope this helps.

5.0_faithful

I'm gonna try that wire dry stuff , and get parts for a tune-up. Thanks and I 'll still look for any other input... You guys are alright !!!!