Hey guy n girls I have a 2002 vx commodore with a ls1. Did my normal 5000k service fluids filters and throttle body clean. Ever since its missed feels down on power. The only thing different this time I have a new exhaust on with decat pipes. Car run fine up until I did the throttle body clean. Has a madness tune by oztrack 4 into 1 s/s tuned headers 3" decat pipes and a 2.5" decat back system. plugs r 5 to 10 thousand old as is leads. Have had a visual at plugs and leads look like new , New fuel filter. Have also had a good look at pcv s can't find a split or anything out of the ordes. Have had it scanned came up nothing no codes being thrown. No engine check light either. My next check will be compression. Have I missed anything here. I can't work it out nor could mechanic

 

did u remove the headers to fit the exhaust?

 

exhaust and headers installed about 5 k ago this was the first sevice since full exhaust system upgrade. I replaced leads and plugs after I installed headers same.day . It was trouble free until I serviced it. Car went perfect until I did a throttle body clean 5k after exhaust fitment .

 

If everything started because of the throttle body then the guess would be a bad gasket or the throttle blade shaft is leaking air. That's assuming you didn't mess with the iac valve and did any idle relearn that the pcm wants.

Of course it could be as simple as not having a sensor fully plugged in. I've had to unplug every major connector and replug them in until I found a plug that wasn't seating correctly on a project car. I eventually replaced the offending pigtail, but not before being very confused a few times.

 

Get a multi meter and ohms check your ignition wires.

And also if they haven't been replaced for years put two new oxygen sensors in it (but it should be throwing a code if the O2 sensors are bad)

 

Coil
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