e6bill
Full Member
2003 Av Z66, 250,000 miles.
I've had a misfire for a long time with mostly a P0300 code. This week I finally took the plunge and pulled the intake manifold to replace the gaskets. Also replaced the knock sensors and harness due to a CEL for the rear sensor (it was rusted badly).
While I had it all apart, I also replaced the injectors.
I got everything back together today and cranked it up. Seemed to run some better at idle, but not perfect. Before, it would shake at idle, but run OK at speed and ping some under load.
Went for an extended drive (30 min) and picked up a flashing CEL after awhile. Had the codes read and came up with P0300, P0172, and P0175 (both banks rich). Never had these codes before now. Was a bit lean before.
Checked for loose connectors, vacuum leaks as best I could, and for loose bolts. All looked OK. MAF isn't dirty, filter isn't nasty.
What might I be missing? Maybe the new injectors aren't up to scratch? Some degreaser likely got on the MAP sensor and might be a possibility. The MAP sensor also seems loose in its port and may have a tweaked seal, but nothing changed when I wiggled it with the engine running.
Opinions?
I've had a misfire for a long time with mostly a P0300 code. This week I finally took the plunge and pulled the intake manifold to replace the gaskets. Also replaced the knock sensors and harness due to a CEL for the rear sensor (it was rusted badly).
While I had it all apart, I also replaced the injectors.
I got everything back together today and cranked it up. Seemed to run some better at idle, but not perfect. Before, it would shake at idle, but run OK at speed and ping some under load.
Went for an extended drive (30 min) and picked up a flashing CEL after awhile. Had the codes read and came up with P0300, P0172, and P0175 (both banks rich). Never had these codes before now. Was a bit lean before.
Checked for loose connectors, vacuum leaks as best I could, and for loose bolts. All looked OK. MAF isn't dirty, filter isn't nasty.
What might I be missing? Maybe the new injectors aren't up to scratch? Some degreaser likely got on the MAP sensor and might be a possibility. The MAP sensor also seems loose in its port and may have a tweaked seal, but nothing changed when I wiggled it with the engine running.
Opinions?