1998 Trans am need help
Thread Starter
Teching In
Joined: May 2014
Posts: 3
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1998 Trans am need help Hi I'm new to the whole ls1 gm motors . First Trans am i got but I don't really know much about em. I picked it up over the weekend drove down to Indiana. The guy told me it had a misfire that comes and goes. It has a 2004 aluminum 5.3 motor in it with a 5.7 intake manifold. 799 casting heads pace setter headers to dual flow masters. I got the car back home looked at it more and found a bunch of vacuum lines not hooked up. I hooked em up ran my obd2 scanner came up with a code for the egr and cylinder 8 misfire. Changed the coil out with a new one and checked for codes again nothing this time besides the egr. Drove the car around the block then it started smoking blue scanned it once again for codes and now cylinder 8 misfire came back, egr and a code for the 02 sensors even tho the car doesn't have em. Before when I first scanned it the code never came up. I need help tryna get this thing up and running right.
Any help would be greatly appreciated thanks
Any help would be greatly appreciated thanks
Could you please post up the codes that are popping up..?
If you've replaced the coil for cylinder 8 with a new one and your still getting a random misfire on it, check the spark plug wire and make sure it's not damaged. Also pull out the spark plug and make sure it's gapped right, check if it has oil or any fuel on it.
As for the o2 sensors, again the codes would help but if they are the back o2 sensors you should have them deleted off the pcm since you have headers, if they are the front ones going off then check the wiring from the o2 sensor to the wiring harness for damage and to test it if it's on one side just switch the o2 sensors from left to right and if it follows you know the sensor itself is bad.
And lastly the blue smoke you mentioned could be oil & fuel mixing. Not good obviously... So you might want to do a compression test and i'm having a gut feeling that it might be in that cylinder # 8 that could be causing it. So when you do the compression test check all cylinders and I believe they have to be within 10 % the highest compression ratio.
Hopefully you check it all before driving it too much, goodluck!
BTW if I got anything wrong please correct me, thanks!
If you've replaced the coil for cylinder 8 with a new one and your still getting a random misfire on it, check the spark plug wire and make sure it's not damaged. Also pull out the spark plug and make sure it's gapped right, check if it has oil or any fuel on it.
As for the o2 sensors, again the codes would help but if they are the back o2 sensors you should have them deleted off the pcm since you have headers, if they are the front ones going off then check the wiring from the o2 sensor to the wiring harness for damage and to test it if it's on one side just switch the o2 sensors from left to right and if it follows you know the sensor itself is bad.
And lastly the blue smoke you mentioned could be oil & fuel mixing. Not good obviously... So you might want to do a compression test and i'm having a gut feeling that it might be in that cylinder # 8 that could be causing it. So when you do the compression test check all cylinders and I believe they have to be within 10 % the highest compression ratio.
Hopefully you check it all before driving it too much, goodluck!
BTW if I got anything wrong please correct me, thanks!
Thread Starter
Teching In
Joined: May 2014
Posts: 3
Likes: 0
Could you please post up the codes that are popping up..?
If you've replaced the coil for cylinder 8 with a new one and your still getting a random misfire on it, check the spark plug wire and make sure it's not damaged. Also pull out the spark plug and make sure it's gapped right, check if it has oil or any fuel on it.
As for the o2 sensors, again the codes would help but if they are the back o2 sensors you should have them deleted off the pcm since you have headers, if they are the front ones going off then check the wiring from the o2 sensor to the wiring harness for damage and to test it if it's on one side just switch the o2 sensors from left to right and if it follows you know the sensor itself is bad.
And lastly the blue smoke you mentioned could be oil & fuel mixing. Not good obviously... So you might want to do a compression test and i'm having a gut feeling that it might be in that cylinder # 8 that could be causing it. So when you do the compression test check all cylinders and I believe they have to be within 10 % the highest compression ratio.
Hopefully you check it all before driving it too much, goodluck!
BTW if I got anything wrong please correct me, thanks!
If you've replaced the coil for cylinder 8 with a new one and your still getting a random misfire on it, check the spark plug wire and make sure it's not damaged. Also pull out the spark plug and make sure it's gapped right, check if it has oil or any fuel on it.
As for the o2 sensors, again the codes would help but if they are the back o2 sensors you should have them deleted off the pcm since you have headers, if they are the front ones going off then check the wiring from the o2 sensor to the wiring harness for damage and to test it if it's on one side just switch the o2 sensors from left to right and if it follows you know the sensor itself is bad.
And lastly the blue smoke you mentioned could be oil & fuel mixing. Not good obviously... So you might want to do a compression test and i'm having a gut feeling that it might be in that cylinder # 8 that could be causing it. So when you do the compression test check all cylinders and I believe they have to be within 10 % the highest compression ratio.
Hopefully you check it all before driving it too much, goodluck!
BTW if I got anything wrong please correct me, thanks!
I'll get you the codes when I get off work and get back to the car it's. I'll do all that and let you guys know what I come up with
