Please help! Idling issues.

[Js04sILVerBullet]

Originally Posted by 1990 NC SSP

Is it okay to add Sea Foam or other cleaners once a month? Will post as soon as I have an update. Hopefully when I get most 87/89 octane fuel in my car it will help the cold idle issue I have. I thought that putting 93 octane in my car was helping, little did I know that it could be hurting my car. Thanks again for help.

It's ok to run the Sea Foam thru the car if done properly, but to much can actually not be good for it.

It's usually a good idea to check your spark plugs after doing it, because it can actually foul out your spark plugs since it works "that good". But again it really depends on how and how much you run it thru the car.

[FHP0827]

I don't think it's any type of "fouling" issue.......unless it's fouled spark plugs possibly. These engines are always filthy inside since they re circulate crankcase vapor back into the intake, but apparently it doesn't bother them at all. Really sounds like a vacuum leak to me is the most likely cause. Incidentally, what kind of plugs are you running in it? I have found that they really don't seem to like Bosch Platinums for what it's worth.

[1990 NC SSP]

I completed a base idle reset again and it seemed to be idling ok. When I turn the heat the idle lowers and nearly turns off. I will see how she runs in the a.m.. My car has motorcraft spark plugs, but it need to probably change them soon for a tune up. There is also a pretty bad exhaust leak on the passenger side I will address as soon as possible. I wish she was ready for the 50th Anniversary Mustang car show in Charlotte, but she is not ready. Maybe I will be able to show my car at the 51st Anniversary next year. Thanks for all of the help.