Why GM 5.7L TBI Truck shows code 44 lean exhaust. Engine light comes on after about 8 miles. Fast Idle after warms up only.
Still sounds like an air or vacuum leak with that high idle...did you check the brake booster, or plug off that line?
Can you observe the cone pattern of the injector spray? Is it a fine mist and a clear cone pattern? No problem with drips or clogs?
One way to check for intake gasket leak into the valley: close off ALL vacuum lines, every one from the intake manifold. Then run the engine and take off the oil filler cap. There should be a slight pressure, but if there is a vacuum at the filler cap, there is an intake gasket leak into the valley. I haven't tried this, but I read it on a buick forum once, so let me know if it works or not.
Jan 22, 2016 |
Cars & Trucks