i just changed the lower intake manifold on my 98 grand prix v6 3.8 not supercharged, but im having acceleration problems, tonight ui was driving the car on the highway doing 90km/h started going up a hill, pedal to the floor and it was only driving at 80 km/h, and would not go any faster but once i get over the hill the accelerations slowely climbs up again, any ideas, please help, ive changed the spark plug wires also

just seems to holding back can someone help me please:th_nervous:, I also notice when the car is in park and i rev the engine up it seems fine! any answers please help, thanks

Welcome to the site!

Would it just not rev past 3k RPM? if so, I would suspect your catalytic converter is clogged and would need replacement.

Are their any SES lights being thrown?

Did you change plugs recently? what are they gapped at?

Where are you located in Ontario?

Sounds like a clogged cat to me.

yes im in ontario, it semms odd that it would be a clogged catalitic converter to screw up on mme right after the job was done, im gonna check my fuel injectors,vacuum lines, cause it could be because not enough gas is going to the engine, once i put it to the floor, the torgue of the engine is not receiving the gas it needs, i dont know!

doesnt really rev past 3k when im driving it, when its stopped in park it does!

the engine is under a much greater demand when its pulling the car then when its in park i say hook it up to a scanner and look at ur intake vaccuum thats the only way i found my clogged if the vaccuum is real low its telling you the engine is working to force the exhaust out. my cat was clogged but it still did its job of cleaning the exhaust so i never tripped a SES light

also how long ago did you change ur fuel filter?

yes, but where in Ontario are you located? Toronto? Ottawa?

After your other posts I really think it is a clogged cat like I mentioned in my first post.

Their is no load on the motor when it's in park so that doesn't matter.

If it were not getting gas then it would lean out and you would throw an SES light, probobly P0171.

im located in timmins up north, ya maybe it just gave out i dont know maybe the best thing is to bring it in but the funds are not there at the moment so im trying to figure this out before thats my option

I don't blame ya. But we have seen this a few times on this board alone.

Oh, I've never been to Timmins but my brother drives up there all the time delivering stuff for Bardon's (company).

You can get a hi-flow cat for fairly cheap. You can even get an aftermarket 3" downpipe for fairly cheap and that would come with the cat.

Try joining OQCGP.net and post a "looking for" thread there and see if anyone has one for sale.

yo i just noticed i have a faily large crack running along my muffler would that have anything to do with it you figure?

no, it would just make your car louder but would have no affect on this.

ok nevermind lol

ill take a looka that site though

No acceleration, although the engine and tranny are in good shape now. You had a leak that could introduce some nasty stuff into the exhaust system. Sounds like my 85 Firebird, and the verdict came back that the car had a bad catalytic convertor and bad tranny rebuild. You said nothing about the tranny, so I'm really leaning towards a cat.

Welcome to the site. Good bunch of folks here that are willing to share their info without flaming anyone. Be sure to post your fixes. Oh, and pics! We love pics here! Be sure to read our FAQ sections.

OH, shut your face, Rick!

Is that considered flaming?

No, Steve's blower is flaming.

Now how am I to close my face? I have no open, festering wound. Unlike that space between your chin and nose.

Wow, I AM good at this, arent I? I should try my hand at that other site, huh?

Hi, Randall. Please dont hurt me. lol

Well let's hope his leaky oil pan doesn't splash any oil on that flaming blower, otherwise those painted flames would be real!

Would you like one? LOL.

i was driving the car on the highway doing 90km started going up a hill, pedal to the floor and it was only driving at 80 km, and would not go any faster but once i get over the hill the accelerations slowely climbs up again, and the tranny seems to be shifting ok

thanks guys for sure on your thought on my problem, definetly alot more info than what ive been getting!

Clogged cat man, we can't put it any other way.

You can get a universal hi-flow magnaflow cat from Canadian Tire for under $100 CAD. Get one of those and have it welded in.

forget that, buy a DP with no cat, then never worry about that issue again

ok well ill go from there hahaha ya im persistant i guess! what can i say !

i have dual exhaust so its gonna cost a little more but ill go from there i guess, hahaha

we have emissions testing up here, we can't run no cat.

running with no cat doesn't free up much horsepower anyway, a hi-flow cat isn't very restrictive and not running one makes your car very stinky.

it's not true dual exhaust and their is only 1 catalytic converter on our cars.

The front exhaust manifold dumps into the rear which then goes thru a single downpipe then to the cat. then a u-bend (get rid of this) then thru a resonator and then after this it splits into the dual exhaust.

What?

oh ok didnt know that!hmm ill have to take a look at the muffler system and recongnize everything!, either way the funds are not there so ill be waiting alittle for that , just got laid off so things are pretty extreem at the moment lol

He thought that because his was dual exhaust he'd have 2 downpipes and 2 cats, so that would be expensive.

Sorry to hear that man, seems to be happening alot around here too.

Here is a pic of our exhaust all laid out. At the top of the pic is the resonator. Just ahead of that, though it's not pictured, is the u-bend that houses your rear o2 and just ahead of that would be your cat and downpipe.

ok but the cat isnt on that pic right !

correct. The cat would be further away from the camera by about a foot or so.

ok im gonna take a look under the car ill brb

ok, but you probably won't see anything wrong with it.

maybe after a few hard WOT runs and highway driving you could look down there and see the cat glowing bright orange.

or if it smells like a POS then you'll know

how do you load up pics on here ill try to take a pic and show ya

upload them onto photobucket, its free to make an account.

then copy and paste the image URL then youre done !

k will do

the FAQ section has all the instructions you will need.

nevermind lol to much work, im not gonna get a descent pic anyways, so its cool

eww, snow, I am so glad that is finally gone for the year!

There isn't really much to show us about the exhaust/cat, you can't visually detect a clogged cat unless you can actually see it glowing bright orange.

takes like 2 minutes lol, but WOW get new headlights ASAP.

i sent some pics not very good but i guess it will do hahaha

i put more pics in the album

i had to jimmy the vacuum ohse the one going to the fuel pressure regulator and the one going to a sensor i think then they both go to the throttle body

ya i hate snow to what a pain in the ass, most of it is going but up here who knows!

holy quadruple post batman.

that is one dirty engine bay.

the vacuum hoses are fine, I have one like that as well using wiper fluid hosing lol.

there ya go lol

ya it has 180000k on er so ya its a little dirty lol

Pic 1 is the res with the u-bend to the right of the pic

pic 2 is, from left to right: resonator, u-bend, cat.

What year GT is that again? 97? Time to clean that bay, dude.

Replace those headlights, quick. Our lights arent the best in the world to begin with, then your lamps have to contend with hazed lenses, too?

I like the color. Has some great potential.

so the cat is the long pipe, before splitting of to the mufflers?

ok i see

wait a minute, I'm doubting myself here. Did you take the pics from the passenger side of the car (as I thought at first, when I posted above), or from the driver side (as I'm wondering now)?

If it is from the driver side, reverse the component locations.

i havent gotten around to changing the plugs yet i know there cheap,but i did change the spark plug wires, im wondering if that would have something to do with it also

no, the long pipe that leads to the split is the resonator. Guess I have my perspectives mistaken.

drivers side

for the GT, use Iridium or Platinum plugs. The copper is for use in boosted or blown applications. We notice better overall performance using the precious metal plugs and OE wires.

its a 98

pic 1 from left to right is: Cat - U bend

Pic 2 from left to right is: Cat - u bend - resonator

ahhhh ok !

ok. From driver's side, cat to the left, then u-bend, then res, then aft y-pipe, then muffs, then tips.

You have 2 O2 sensors: one on the down-pipe after the forward y-pipe, and the other in the middle of the u-bend.

Once you replace the cat with a high-flow magnaflow/3" d/p, replace the O2 sensors as well. Expensive, but worth it.

cool!

Darn you, Randall! This was MY baby! You go and take your bolt-ons and play somewhere else! Let those who are man enough to get things done on engine alone talk like adults. Take your riff-raff elsewhere! LOL

j/k, Randall. Thanks for pitching in.

haha, sorry but I always thought my elders were wiser, you really dropped the ball on this one, Rick. tsk tsk. How can you live with yourself? :p

It took me a second to figure it out as well hah, I forgot the stock cat was so long and triangular shaped so I had immediately assumed it was the resonator.

I wouldn't replace the rear o2 though, it's really not needed.

thanks guys deffinetly appreciate the help!

Oh and Rick, if you pay for shipping I will give you my blower but you gotta promise to put it through it's paces! Then we can both talk riff-raff.

And no problem Jeff, hope you get it all straightened out, let us know how it goes.

ya well my buddy had to get all 3 o2 sencors changed on his tahoe they seem to all go at once or it started with one then the other i dont know but the mechanic said hes never seen 3 go out at the same time !

i will for sure !, thanks again, i guess ill go from there well see what happens

That would kinda bite.

what would the shipping be for a blower and intake mani from the frozen wastes down to the Deliverance location?

WAIT! WHAT AM I SAYING!!!

Shipping only for a blower and the manifold, huh? we just might be starting to talk here...

Well, actually it is just the blower, I still need my LIM. The blower is just one of a few parts you'd need. Either l67 heads or a machined LIM with injector bosses, fuel rails, pulley/s and possibly belts depending on how you went. Oh, and a tune.

BTW, it's no longer frozen where I am lol, it's getting nicer.

I do believe shipping is a little pricey because of the weight. Andrew (4drgt) shipped a blower to my area and it cost him quite a bit I remember, you may want to PM him and ask if he remembers.

It's only fair that a nice GP like yours has something that whines in the engine and not just in the passenger seat! (tell your wife I'm sorry lol, I'm sure she is a lovely woman)

Lol. Rick's wife is the brunt of every joke today!

hahahaha!

I sure tend to like my wife a lil. 'Sides, she spends a vast majority of the time driving the GP now that I have my F-body.

So instead of the frozen wastes, it's just the wastes?

The top-swap part requirements are all in the FAQs by now, so if this is something that I wanted to pursue already, I can just look up the rest of the shopping list.

So, are you the one in the passenger seat whining while she is the one driving?

All the more reason to top-swap. I can just see it now, you always wanting a fast car so you're cruising in the Camaro when all of a sudden some hottie in a red GP pulls up next to ya, rev's it, rolls down the window and BAM, it's your wife, then she blows your doors off with the blower, beats you home and to add insult to injury she leaves you to bring in the groceries. It's a cruel world.

It's more like the sandy wastes right now, they haven't cleaned the roads up yet so their is all the left over sand and salt.

Yep, all in the FAQ and countless threads. If you seriously want to do it, it's yours. I offered it to my brother for his Imp but I don't think he wants it.

not sure if this is the path I wanna pursue right now. Lemme check shipping costs. how big of a box? how heavy?

I think the supercharger is 30 pounds. Box size doesn't really matter and I'm not sure the size.