Thread: Throttle Body? MAF? What is what?

Hello! We just got my son a 2005 Grand Prix 3.8L. His car will start, idle hard then stall. If we give it a little gas when starting, it fires right up. It does not do this every time.

I've poked around the forums enough to know that I should try cleaning the throttle body. I am a newbie to shade tree mechanics, so bear with my "stupid" questions. I have attached a photo to help clarify any words I happen to type here that make no sense whatsoever.

So, I had my son put the car in ON and press the gas to open the throttle body valve. Sure enough, the inside (closest to the engine) looks black and gunky (verified by the thick nasty stuff under my fingernails after reaching in there). Okay, I bought the Throttle Body Cleaner I've seen on here.

Before I go spraying inside there, I read that I need to remove the MAF. I have conflicting posts as to just where the MAF is located. I thought the MAF was the black plastic thing attached to the side of the TB. But, I read that the MAF is actually to the RIGHT of the TB between the air filter and the TB. I have no idea.

I am trying to clean the TB without removing it from the body of the car because I am pretty sure I would fudge it up. Can a TB cleaning be done while it is still attached? I have read posts where the poster said they "just sprayed in there and wiped it clean" - though I wonder how they cleaned it because I cant get my fingers in there to save my life.

Do I need to remove the black plastic thing on the side of the TB before cleaning? Would it make it easier to clean? Should I just roll the dice and remove the whole TB to clean it?

Sorry for my convoluted question, but I do not want to mess it up nor do I really want to take it to a mechanic if I can do it myself.

Thanks!

Originally Posted by Hippo Machine

Um? no. don't ever clean your maf with anything other than MAF cleaner. And this forum is very active with alot of people who know what they are doing.

i have recently come back on here. If i'm wrong I'm wrong

Hippo: Thanks for the link! Though that article wasn't for my son's model year, the article you sent me to had a link that DID work for me (er, well, I guess we'll figure THAT out tomorrow, eh).

I appreciate the help!

Not sure why someone would recommend going to a Mustang forum, but thanks for the reply.

Thanks to everyone else for pointing me in the RIGHT direction. :-)

I realize this is not a big deal to motorheads, but for a newbie, I have managed to change out the passenger headlight wiring in the car and, with my Father-in-Law's guidance, change the oil in the thing.

I will unplug the MAF and see if it behaves better. If it does, I'll know to replace it. Thanks for the tip!

Thanks, me too! It has about 206k miles on it, and aside from a few ticky things (like this TB/MAF thing), the car is in WONDERFUL shape. It has great pick-up and drives like it was new. We had to change the oil because the previous owner hadn't changed it in.. umm.. probably 50k miles. Seriously. Nasty and very little left in there. UGH. Of course, the reason there was very little? Ah, yes, that would be the "hey, I think 'finger-tight' should hold the filter on..." they had done. Yeesh.

I digress (often).

Anyway, he LOVES the car!

Oh, and sorry for the reply to my reply, but I disconnected the MAF and the problem persists. So, that should mean the MAF is okay, right? Tomorrow: TB removal and cleaning. Wednesday: take car to REAL mechanic.. Haha, just kidding (er, I hope)!

Originally Posted by 01gpgt01

Why do you come on here and tell people to go to mustang forums?

because there are many people who go on there with problems with something other than Mustangs. There is also alot more traffic on it. People with Hondas occassionally ask advice on there. Sorry for the suggestion guys....jeez

So far, I haven't been able to do it. Yeesh. Give the boy a car and he thinks he can just get in and drive it! Haha! Looks like this will be a weekend project (meaning Saturday, most likely). I was going to do it last night, but the engine was too hot when I got home (he had driven it to school) and it was too dark by the time things cooled. I did unplug the MAF and the car ran the same, so that (according to what I've read here and other places) means the MAF is most likely *not* to blame. I am going to go ahead and clean it too though, since I'll already have the thing apart.

I will update when I get the job done (good, bad, or ugly).

UPDATE: The deed is done! It took longer than I expected, but only because I did not have a small wire brush to help get the *crud* out of the throttle body. Also, when you read "coolant will leak out," that is no lie. it is only about an ounce or so, but it can make a mess. in my case, I had loosened the top bolts to the TB first, so when I loosened the bottom ones, the TB tilted forward a little. the coolant ran out of the TB through the body itself. I had envisioned it coming at the marriage wall. Nope. So, my carefully placed rag (to catch the coolant) was useless. Just watch for that when/if you try this at home.

The unit itself came out fairly easy enough. A lot of folks complain about the location of the bottom two bolts. You *must* have a 10mm deep socket. Period. it helps you get in there and the bolt on which the nut is attached requires a deep socket.

All tolled (yes, I spell it that way, even though many don't, but that is a story for another time), it took about an hour to clean. This was because of the lack of stiff brush, but also because it had 206,000 miles worth of buildup. I used short, small bursts from the cleaning fluid. Then I wiped it with a rag. For a couple spots, I sprayed and immediately (gently) used a brillo pad to break through the top layers.

this is a "rinse, lather, repeat" kind of deal. Take your time and eventually, you will see shiny motor parts again!

When I connected everything back up, we fired up the car, and it ROARED to life! Holy cow, what a difference! The car starts great now and sounds like it did when it was first put on the dealer's lot six years ago, I imagine. Wow!

Thanks to everyone for the tips! The only thing I suggest in addition: buy a new TB gasket ring for good measure. Ours looked and felt fine, but I would sleep better knowing I had a brand new one to go with the shiny clean TB.