Seafoam ?

So...

what's the verdict on this stuff? I have heard some that swear its the best thing since sliced bacon, and some that claim it does essentially no good...

I ask because (along with my oil burning issues) my idle recently started to act up. It is not too bad, but when I am sitting at a light, it will not idle very smoothly, it will sit at about 900 rpms and then every few (maybe 10 or so) seconds, it will drop to around 700 and jump back up... it makes the engine shake a little too that I can feel in my pedal. It seems like it usually does not do it quite as bad if the car is in park, but sometimes it is just the same regardless of park or drive...

I don't know what is causing it - i recently replaced the PCV and air filter. To me, it feels like I've got a vacuum line that is acting up (not completely off, because it would probably die, not just idle rough, right?) but maybe like not exactly on like it should be... But I couldn't find any that look astray or screwed up or anything.

So I thought, maybe if this Sea-foam stuff works, I should throw some of that in there and see if cleaning the injectors/valves/etc might get rid of my problem...

How much is a can, just like a few bucks? If so, I'll go ahead and give it a shot (assuming some of y'all think it might help)... If it doesn't help, I'm probably gonna go and get a tune-up w/ new plugs this weekend and have them take a look and see if there really is a vacuum line that I can't see causing problems or something...

:banghead:

and my buddy last night who drives a 05 Mustang (the base version, not the GT) was convinced that his car was faster than mine... I wanna smoke him b/c I know that I can, but I want to make sure I'm running at full potential before I make the challenge... Looking at specs, I've got about 40 hp and about 65 ft-lbs of torque on him, and I weigh in about 35 lbs heavier - but he weighs about 35 lbs more than me, so there's your offset there! :evillol:

Ideas on my rough idle?

I believe that Seafoam and lucas make the two best fuel system cleaners out there, as far as pour-in-tank cleaners go. I believe Trans-X is the best trans treatment out there. Don't expect any treatment to work once the injector/valve/solenoid is completely stuck/clogged, as the treatment can't help what it can't reach. I'd give the Seafoam a shot, it's relatively inexpensive, and there's a good chance it will help.

is it just as simple as pour the can in the gas tank? Looking at seafoam's website (http://www.seafoamsales.com/motorTuneUpTechGas.htm), it says you should put it in the throttle boddy throat, in the gas tank, and in the crankcase (which would mean I'd need a few bottles)... I would imagine I should follow the directions on the bottle and go for all 3. I am a bit lost on exactly where I should put it in under the hood? The website gives a couple of different places depending on engine type. I got a 98 GP GTP.

Any help is greatly appreciated - I'm gonna try this and hopefully clear up my problem this evening

Might want to check the Idle Air Control valve (IAC). It's in the throttle bore just above the throttle position sensor.

The pintle will get carbon on it from the EGR valve and can cause a rough idle.

The SeaFoam won't hurt and it's only about $6 a can. Be sure to mix it with a FULL tank.

Your car has multi-port injection, and the upper plenum is air only. DO NOT pour the seafoam into your throttle body, they are referring to old TBI units, not MPI. Put it in the tank as you fill up, that way it gets mixed up thoroughly.

good, i didn't. I put a can in the gas tank last night...

I think it has helped, but it has not eliminated the problem - although I would imagine that it will take a little bit more driving before the effects really take...

might go ahead and get a tune-up this weekend anyways... will update

oh, one thing i noticed - tell me if this is odd or normal.

When I was about to put in the Seafoam, I thought I was going to have trouble, as I only had a funnel with a short neck on it. But it worked fine because that little metal piece that covers the neck going to the gas tank ("under" the gas cap) was not completely shut, like the spring that keeps it shut was bad.

Does that little piece have any effect, I mean - I just got an emissions check done, and they check the gas cap, and it was good...

maybe nothing, but just something I remembered, and thought, hmmm...

The metal flapper is just a "vapor block" so when you pull the gas nozzle out of the neck, it shuts off and keeps vapors from entering the atmosphere.