Thread: Car Dont start after engine swap

Hi guys ..changed out 3.8 L in my 2005 grand prix and now doesn't start. Car has spark at plugs and there is pressure on the fuel rails...any ideas as to what may be the problem?..The motor is out of a 2005 grand prix as I was told.

Thx for replies

Originally Posted by Scottydoggs

double check all your grounds, starter wires and harness plugs are in place. icm ground too.

Everything is hooked up including the icm ground and the 2 grounds on the bell housing bolts...1 thing I thought of was the salvage yard said the motor has been sitting inside on a shelf for a quite few years(it turns over fine thou)....it only has 43000km at least that's what they told me and wrote on the bill. I used the wiring harness off my original motor( the one that plugs into the icm , crank and cam sensor as the salvage motor had a wire broke at the icm connection plug(I also took due care in routing it around the crank pulley to make sure it was in the wire secure clips so there was no chance of it being damaged.
I. After it didn't start I swapped the whole coil pack.

Originally Posted by Scottydoggs

oh and my car has 3 grounds to the bell housing, one fat cable, the bat neg ground, and two thinner wires.

Hmmm mine only has 2 connecters at bell housing grounds...unless there are smaller ones going into one of them....cant look at the moment as my car is in my sisters garage.

Originally Posted by machinegunsquid

Since you say it has spark, I'm assuming the motor turns over freely?


Make triple sure all spark plug wires are routed correctly.
Make triple sure all fuel injector connections are correct.
Make absolute sure the crank position sensor is plugged in correctly, same with the cam position.

Once that's done, let us know if it still wont start.

Spark plugs are wired correct....fuel connections are labelled so i'm sure they are right also....and crank and cam sensor are plugged in right .

Wouldn't the engine light stay on at the key on position and not turn off until the engine started?

Originally Posted by Scottydoggs

try a shot of starting fluid in the intake. maybe its got cob webs inside it.

you did give it a tune up right, new plugs and wires?

yes new plugs and wires on it.

Originally Posted by Scottydoggs

mines a 98 so yours maybe different, cant hurt to look for a stray laying around. some cars dont fire up due to one of the grounds being broken off the eye loop.

Worth a look when I get up there tomorrow, but I don't believe that is the problem as I didn't see them when I put 2 new tranny lines on it as they looked seedy and may have a small leak in 1 of them and it so easy to do when the engine is out.

If the motor that I put in wasn't the same year as mine.....would the knock sensor stop it from starting?

Could get out a multimeter check to see what your getting at the injectors. Did you do a compression test when you put it in?

Sent from my LG-L38C using Tapatalk 2

Originally Posted by chamberlain198437

Could get out a multimeter check to see what your getting at the injectors. Did you do a compression test when you put it in?

Sent from my LG-L38C using Tapatalk 2

Didn't do a compression test...not sure how to check the injectors, but I could always google it

Originally Posted by Scottydoggs

do this^^^^^^ see if the the bulb flashes. sounds like your injectors are not getting power. check all the fuse box fuses and make sure everything is plugged in.

just turn the ignition to on or all the way as if I was gonna start the car?......also do I have to do this to each injector?

Lets us know what you find out. I hope you get it figured out soon, I'm sure it's driving you crazy...

Sent from my LG-L38C using Tapatalk 2

Originally Posted by chamberlain198437

Lets us know what you find out. I hope you get it figured out soon, I'm sure it's driving you crazy...

Sent from my LG-L38C using Tapatalk 2

Is it ever!