replaced engine in car, but something is messed up [Archive] - Forum


View Full Version : replaced engine in car, but something is messed up

01-15-2004, 09:39 AM
well everybody, i replaced my 2.4L engine in my 97 grand am gt this past weekend, but there is something wrong, i have black smoke coming out of the exhaust and lots of it.....does anybody know what is causing this? and if so how do i fix it?

01-15-2004, 10:45 AM
Any SVS or SES lights? Did you make sure that all of your sensors are hooked up and working properly (especially 02 sensor)? Those suggestions are a good place to start....


Paul Reed

01-15-2004, 01:25 PM
yes, we went through and double checked all of the wiring, everything is hooked up correctly, and my buddy also has a grand am, same yr. and everything, so we used that car as a model when we put it all back together. the low coolant light is on for some reason, and the check engine light is on. i think that some of my plugs might not be firing at all times, so i might try to replace the plugs. if that doesnt work then im out of ideas

01-15-2004, 07:08 PM

Black smoke is usually unburned fuel getting into the exhaust system....either from an overly rich tune or possibly a problem with the timing. How does the car run? Smooth or rough?

I'd have the coil tested at an auto parts store just to be sure....most do that for free.

Possibly faulty ICM?

Are the spark plugs new and gapped correctly?

Are the plug wires in the correct location?

And where did you get the motor from?? Possible that the assembler is at fault and screwed up the many possibilities....

01-15-2004, 08:13 PM
um, the car has fresh gas in it, let it run for about 20 min. and put dry gas in. the plugs are good, they are from the old engine, and they were practically brand new. im gonna try to change the plugs tom. and see what it does. it does run really rough though.

01-15-2004, 08:35 PM
My vote goes to plug wires not in correct order.

01-15-2004, 08:39 PM
there is no plug wires on a 2.4
Sounds like timing, or a stuck injector.

01-15-2004, 08:42 PM
??? No plug wires? Okay... news to me :D
Yeah probably timing then.

01-15-2004, 08:50 PM
sounds like a bad engine... might have to try another lol joking!

might be kinda odd, but check your spark plug gaps.... should be .060

and if your check engine like is on... DEFINETLY get a code reader. it should tell you whats up.


01-16-2004, 10:33 AM
well, i figured out why it is smoking! bad news its cause there is gas in my oil.......not good, could this be from a messed up injector?

01-16-2004, 02:23 PM
or bad rings.

01-17-2004, 12:22 PM
You have any weird sounds coming out the engine block?
my cuz 96 grand am has a bad cam in it and it was getting gas in the oil b/c the valves not moving - had to take the covers off to find it

01-17-2004, 03:31 PM
it runs really rough, but there isnt any weird sounds, just runs rough and has black smoke coming out the exhaust........

01-18-2004, 08:10 PM
umm well then check u'r vacume lines with a tester, sometimes they get suction locked and that the PVC valve has not failed.
Just think off the top of my head now lol g/l just the same

01-18-2004, 09:13 PM
it is running good now, just changed the plugs and it has been running good for 2 days now

01-19-2004, 07:17 AM
Great new :)
sometimes the easy things are a pain hehe
hope that gets all the problems done

01-19-2004, 09:01 AM
IF you had trouble starting the engine initially you will get gas in the oil. YOu should change it asap though, thin oil will mess up your engine.

01-19-2004, 11:55 AM
ok, will do

01-19-2004, 02:02 PM
sounds like you got a bad salvaged motor.Sorry to here that.Maybe try a rebuild next time, eh
In most older cars I've owned .Black smoke is usually the sign of burning alot of oil.A cracked head maybe .Bad gaskets.Or blown piston Rings are usually the culprits....

01-20-2004, 08:32 AM
no more black smoke! no more anything, its running great ( knock on wood ) thanks to all for your help!