[cfiiman]

Hey all,

I just finished tuning up my stang (90 5.0)...Put in new plugs, wires, cap, rotor, air filter, checked MAF to make sure it was clean, and set the timing...Car runs really good it seems except for idle...And at idle it is not bad the rpm gauge does not jump around or anything, it just seems like their is a little more vibration than there should be...The steering wheel vibrates a little...I guess I'm having a hard time explaining this but it just seems like it is not as smooth as other "newer" mustangs that I have test driven...Maybe this is just the way the 87-93 5.0's were but I thought I would ask...Like I had a 05 v6 for a rental car the other day and when it was at idle it was so smooth...My car does have 130000 miles on it so I'm sure that may be part of it not being as smooth as a new car, but is there anything else I can do on the tune-up that will make it smooth out or is this the way all your 5.0's are too?

Thanks,
JSK

 

[ocgirl]

I was having the exact same problem with my 96. Hard to describe except sometimes a bad vibrating at idle, worst if it was in drive. Car drove great rest of time. I took it thru inspection and it threw off codes. One was involving the Purge Canister solenoid system. I checked the canister and lines, all good. My solenoid was bad. I removed it yesterday. Right now running without it while I go up to pick up the new part in a couple hours. Even without it the vibration has stopped 90% of the time. It still doesn't idle quite right but the difference is bad enough that i'd bet this is where the problem is coming from. Have you seen if you have any codes?

 

[cfiiman]

Thanks for the reply, no I haven't checked it for any codes but I should...Is there a way to jump it to make the light flash codes????(I do this with my blazer)...When you say bad vibration how bad is it...Mine is not that bad...It is more just that it is not as smooth at idle as other cars i've driven...

Thanks

 

[ocgirl]

my vibration wasn't that bad at first. But over the course of a couple weeks it got worst. It only does it while idling. It is much worst in drive. Alot of times it comes to a complete stop when in park but sometimes it still does it in park, only much less worst. If you have an autozone near you they can pull the codes for you. My check engine light was on as well. If your light isn't on there may not be any codes. When I bought the car the previous owner had disabled the check engine light and I didn't notice it.

 

[jerry_dawg]

My 5.0/auto idles butter smooth. Well one time it didn't, I got done setting the timing after installing my intake and forgot to plug the spark plug wire back in... Genious! Suprisingly it wasn't that bad, must be the 7 extra cylinders.

 

[cfiiman]

jerry, i'll check that...you mean it could run and drive ok and even squeal the tires a bit on 7 cylinders...I just think I would have noticed that...I mean wouldn't it be much worse?

 

[meangreen92]

Verify 13726548 firing order. Could also be a bad balancer giving you an improper reading.
You should scan it for codes and check the fuel pressure. You want 39-40 lbs.