Its '91 auto maro 3.1 50,000 miles. Ever since i got it ,it idle a bit funny, also when I take of from stop it some times feels like its running out of gas. Fuel pres okay, idle sensor okay.
When I get gas it has a LOT of presure from the tank, and purge valve runs VERY hot. Can this be connected???




Thanks .

 

Change the fuel filter

 

Also check for vaccum leaks. Your car is 11 years old the rubber and hard lines are most likely brittle and could most likely stand to be replaced. You can fix and broken or bad spots in the hard lines by using a pice of rubber hose and lsip it over that spot. Check you air filter a cloged air filter can cause this problem to.

Have you given your a major tune up sence you baught it? Most of the time when you buy a used it is in desperate need of a full around tune up. Including a new fuel filter that was suggested above.

 

I have done complete tune up as soon as the car came home and fuel filter. checked no vacume leaks.


Any ideas??

 

the lack of power can be timing. set to around 12-13. Mine(AND OTHERS) have said it works alot better.

 

Maybe your throttle position sensor is worn out. A bad one can cause a rough idle. Have you checked the computer for codes? I assume the SES light hasn't come on, but maybe there's a code anyway.

Check for exhaust leaks, too. Pull some spark plugs out, and check the gaps on them to make sure they didn't widen out past 0.045". Also, see how "clean" they are. If they're very dirty, they're either the wrong heat range, or you might have a weak spark. A plug that's too "cold" (heat range) will not reach it's self cleaning temperature. Your plug for your 3.1 has a heat range of "3", which is hotter than the range "2" for the 82-87 2.8's. If you had a range "1" plug installed, that's a cold plug, and the electrodes would look black & oily.

Does this happen all the time, or just when it's cold out and first started, or when the engine's hot and running for 3 hours, or ... ?

 

I put in new ngk plugs, they looked very good after 2,000 miles.
Cold it starts normal, then for about 10min it will boog alittle at low throtle. Then it gets better, but still boogs a little on tack off, unless i give it more gas. Other then that, the car runs great, lots of power for V6

 

My car was doing something like that. It would give a little bit of rough idle and when I hit the gas, it feels like it would only let a certain amount of power go, then I press it a little more and the same thing. It was a wierd hesitation. I replaced the HEI module this week and it seems to have taken care of the problem. I hope this helps you a bit.

~Josh~

 

Have you checked the timing?

 

Its fixed :lala:
It was the vent hoses going from the fuel tank to the charcole canister. The insides where flaking, causing small pieces of the hose to get stuck in the purge valve, causing it not to work all the time. This caused a vacume leak.
I replaced all of the ruber vacume lines in that area, and sprayed the inside of the purge valve with WD40 to clean it out.
Now the pugre valve works like it should ( cliks everytime)


The car never ran so smooth :hail:


Thanks for all you sug. I hope this can help someone to..

 

Thanks for the update! Glad to hear you found the problem. I should replace those hoses on my car... the outsides of the hoses look bad, like the hoses are ready to disintegrate.