HELP- 1993 grand prix 3.1L - back exhaust smoke, intake backfire

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test - 25 May 2005 16:26 GMT

the car was running like crap, and i noticed that the ignition
pack was cracked and arcing, so i replaced it with a used one,
and it started up fine. and i was doing an "idle learn" for pcm
and the idle came down and it started to surge. then after a
minute the idle leveled out and about 5 minutes of idle i was
going to turn it off, wait 10 seconds and start it up again to
finnish the idle learn when it wouldnt start without giving it
some pedel. and when i ran it it wouldnt idle and puffed black
smoke like mad. and it was running like an alchohol funny car.
"not so funny" heheh i wasnt impressed as i just purchased the
car and was planning on swapping a 2.8L i just put $4K into of
performance and rebuilding.

my guess would be intake gasket?
i want to swap the motor and use the 1993 pontiac topend(gen
3??) on my rebuilt 1988 bottom end 2.8L.

i just dont want it to act the same, hopping its not the pcm
would a sensor cause it?

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Shep - 25 May 2005 21:32 GMT

Check fuel pressure, possible vac hose offe the reg, or it is leaking fuel
into the vac. hose? Also I believe you have a map sensor on that engine?
make sure you have vacuum to it, no check engine lite?

> the car was running like crap, and i noticed that the ignition
> pack was cracked and arcing, so i replaced it with a used one,
[quoted text clipped - 21 lines]
> * http://www.newsleecher.com/?usenet
> ----------------------------------------------

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test - 26 May 2005 04:08 GMT

yes s.e.s light comes on once in awhile, runs better when light
is out sometimes .. doesn tlike the settings it "learnt" ? so
runs better when light is on "pcm returns to set pcm settings"?

today i wrode in it and it starts better... it sometime idles a
bit chunky after start up.... and when you feather the pedel it
runs decent(not good) but trying to get up to a speed it starts
to hesitate and buck. flooring the car to the mat, it doesnt
hesitate, but get syou up to speed pretty quick.
at a set speed say 100K/H it bucks/hesitates. so im guessing
that it might be T.p.s ? it doesnt like an RPM/or throttle
position?

the car is at my bros house, and my tools are here, so sometime
afer work i might stop by and check the TPS, and see what codes
the engine pcm is throwing. (prolly 12) lol *rolls eyes* i dont
have a fuel pressure gauge, and not sure how to test the MAP
sensor
it also has a air density sensor? in the airbox.

id love to get this motor running good before i do the big swap
otherwise wifey is going to get pisse dif i do the swap and its
still running like crap. hehe
shes allready throwing the "coulda got a newer car" card hehe

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=?x-user-defined?Q?=AB?= Paul =?x-user-defined?Q?=BB?= - 26 May 2005 04:33 GMT

A tps won't make fuel smoke out the pipe.
Shep is correct.
Pull the vac hose off the pressure reg and see if gas comes out
or if you can smell raw gas in the hose.

> yes s.e.s light comes on once in awhile, runs better when light
> is out sometimes .. doesn tlike the settings it "learnt" ? so
[quoted text clipped - 20 lines]
> still running like crap. hehe
> shes allready throwing the "coulda got a newer car" card hehe

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test - 30 May 2005 23:44 GMT

UPDATE---

no gas in vacuum lines
T.P.S reads .46 closed / 4.20 wideopen, with smooth operation on
the digital volt meter

when it starts it doesnt need and pedel anymore, it runs a touch
rough then imediatly revs up and then i heard a clicky-bang
sound and it whent down to idle rpm and was running smooth

still acts funny when you drive it (as described before)

i felt the exhaust while it was idling and it felt very weak,
not like my 2.8L which litteraly throws your hand back with each
lump of the exhaust. lol. although it is done up max
*dreams* cant wait to get that motor in there *dreams*
i just want to make sure that the 3.1 in the grand prix runs
like its saposed to befor ei swap the motor, cuase then if it
runs the same, its going to be a big mess diagnosing it with a
supped up motor ?

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