This is concerning my 2002 Grand Prix GTP w/3.8 supercharged engine. I am going to be changing my fuel injectors out pretty soon. Anyone here know how much work this going to be? I scoped it out, and it looks pretty simple, (famous last words...). I can hold my own as a mechanic, and I've already replaced the injectors on my 280zx. The fuel rail on that thing was a bitch to get back on! Anyway, it's my wifes daily driver, so I can't afford mistakes or very much down time! Thanks, Brian
i haven't done it before, but if i could guess.... injectors are on the intake.. so take the "3800 series II" engine cover off... i think they just clip in... not positive but check it out, i'm doubting it's very hard
My dad change ours one time and didn't have any trouble. By the way, have you ever had any trouble with your mass air flow censor? The one on our 93 Bonneville keeps messing up.
Pretty straight forward repair. Why does it need injectors?? Early 90s GM MAF sensors failed often. Are you buying reman or new?? John
This an '02 so it probably different to the early 90's. The reason for the injectors is, it has been surging at idle for a mothn now. Just over the last few days it has gotten a whole lot worse. If you are stopped in gear or in Park, doesn't matter, it will start revving up to about 2400 rpm and then right down to 200 rpm, then up, down, up, down, until you rev it or take off. When it goes down to 200 rpm, it shudders and almost dies, but jumps right back up to 2400 just before it is able to die. I caught the SES light come on again, and it flashed 40 times then went solid. It has done it before, but this time I counted. (which probably won't tell me jack anyway!). I took it to a local shop that I trust, and they said for what they get get out of the scanner, it's pointing to the #3 injector misfiring. Some of the codes point toward that, but they felt I should have a dealer check it out. They didn't want to start guessing and run up a bill. The codes were " injector misfire" And, it smells like it is running rich. My fuel filter is new, and the car has 57,000 miles on it. No ignition parts have ever been touched on it. I'm thinking I may just buy a whole set of performance injectors and be done with it. But...... if it doesn't fix it, then alot of money for nothing. I'm always glad to hear any kind of ideas, "cause you never know what may fix it. Thanks, Brian
just for the record. before you plunk down $60/injector do yourself a favor and head on over to either www.clubgp.com or www.regalgs.org and ask around. both boards have fairly knowledgable people who could PROBABLY answer this for you for free. it doesn't sound like an injector to me though.. sounds like a computer issue... give those sites a try, i'd try regalgs.org first they're typically more civil.. go give clubgp a try if they can't answer it, more users there but is full of BS too.
Brian, Before you go the injector route, I would check the Idle Air Control Valve. While your at it, remove the throttle body and clean it. This does not sound like injectors to me.
It sounds like the throttle body to me. Im with Larry on this one. Clean the throttle body and plate first! Bet thats the problem. Very common.....
Thanks guys for all of the good advice I have so far! :TU: That's one reason why I use that shop. They are car guys and are cool enough to say they aren't sure rather than gouge me trying to fix it. They checked it out and replaced the fuel filter all for 37 dollars. And that's parts and all. I feel they treat me right every time I need something just checked out, they sometimes don' even charge me for it! They also did my exhaust. I can't help but wonder if it possibly plugs or wires, but they did say it was throwing injector misfire codes. Thanks, Brian :beer
i would have to agree with lary because my truck had the same problem. all i did to fix it was clean the idle air contrle seleniod and the vavle it controlled with carb cleaner. drives like it was brand spankin new!
I will certainly check out the throttle body and the Idle Air Control Valve too. Any recommendations on the proper cleaners for those parts? I want the good stuff! I want to do it right! There is a ton of sprays and such and it makes it a guessing game....... Thanks, Brian
The injectors on the SC motor are in the head not intake as there really isn't any. I just pulled mine and had them cleaned and flowed and o-ringed. Amazing difference ....car starts IMMEDIATELY now. Hot or cold. Well worth the $$$. I am told cleaned OEM injectors are better than most replacements. Job isn't hard. Unplug all injectors, unbolt fuel rail, pull rail off with injectors attached. Vacuum out injectors holes....keep it clean. But...I say your problem sounds more like IAC. Bruce
Sounds like a code P0303. Cylinder #3 misfire. If the SES light was flashing that means the ECM shut down that injector to save the cat converter. I would look at the ignition system first. Either way the major change in idle RPM does not sound like an injector or ignition problem. I would look for vacuum leaks. Also pull the MAF sensor and clean it. Use an ELECTRIC PARTS CLEANER not carb spray or brake clean. You may need a scanner or scope to fix this one. HTH John
Brian, The guys over at www.regalgs.org all seem to speak highly of Seafoam products. They make a cleaner that decarbonizes the throttle body as well as the combustion chambers. GM also makes a carbon cleaner. You introduce it into a vacuum line until the engine stalls, let it sit, then start it back up, and beat the balls out the car. I think I would do a good cleaning of the IAC valve and throttle body. It can't do any harm, and it's cheap. The cylinder misfire could be a symptom of another problem. The OEM wires on these cars are spiral core and excellent. Sometimes they are damaged when they stick to the plug, and you forceably remove them. When was the last time you changed the plugs? Here's the site for Seafoam products. http://stevenbigler.tripod.com/scoutco/id12.html
Larry, the plugs are original. Nothing has been replaced on it yet. I will try the cleaning idea that you have posted, along with some of the other ideas also. Since it starting doing this, it went from maybe once a week, to every time you drive it. Then it went from hardly ever to everyday within about a week. I probably won't be able to work on it untill the weekend. I will check out that regalgs.org site today. Thanks, Brian :beer
sea foam is great stuff! i use it every time i change my oil. the first time i used it it was a night and day difference in the way the car started and performed. also my gas milage went up. just be sure that you use it in a very well ventalated area like outside! i would recomend putting it in through your brake booster hose. this is the easyest hose to find and most of the time the easyest to get to. hope you figure it out curtis
Brian, I am sure all here mean well but....... They're all guessing!!! Including you. Yes, you probably needed a fuel filter, your throttle plates could use a cleaning, your injectors, although a poor design should not have failed....yet. Before spending any more money GUESSING what is wrong, go FIND A GOOD SHOP. You stated how good the shop you currently go is because sometimes they dont charge you.... (not a good sign) or tell you when they cant figure something out. This screams to me thay have no clue!!! They might be great people but to tell a customer to go to the dealer......GEEEZ :rant: You will save money paying a professional to diagnose the symptom and then repair the failure. A misfire code is not an injector code. It could be caused by numerous things. You can find a quality shop at www.ase.com www.asashop.org www.1800autotalk.com Or just take it to Oakville Automotive, 3001 Telegraph rd St Louis. (he's the closest shop I know near you)
