Replaced valve seals timing chain and intake manifold gasket....head gaskets as well start up the vehicle has shaking rough idle but clears up after 2500 rpm.. 3000 rpm is perfect. The test drive feels like decent low rpm is crap... also would like to know if I have a wire in the wrong spot do not have a diagram for coil to plug..No smoke I'm about to set it on fire and push it over a cliff no intake vacuum leaks.....idk what to do (will a off timing chain allow it to idle rough and be perfect at 3000 rpm????)runs sooo smooth at exactly 3000 rpm, also will this idle clear up after being driven?? It seems to (almost) disappear after warm thanks Matt 9807299880 My car has 187000 miles. My car has an automatic transmission.
My car has 187000 miles.
My car has an automatic transmission.
This may be a sign of a faulty MAP sensor as the vehicle responds adversely to a load put on the motor (i.e. putting it in gear, making turns (which makes use of the power steering pressure switch) turning on AC or engaging the brakes). The Manifold Absolute Pressure (MAP) sensor senses engine load and generates a signal that is proportional to the amount of vacuum in the intake manifold. The engine computer then uses this information to adjust ignition timing and fuel enrichment. When the engine is working hard, intake vacuum drops as the throttle opens wide. The engine takes in more air, which requires more fuel to keep the air/fuel ratio in balance. When the computer reads a heavy load signal from the MAP sensor, it adjusts the fuel mixture to slightly more rich than normal so the engine can produce more power. The computer will then retard (back off) ignition timing slightly to prevent detonation that can damage the engine and decrease performance. This may also be caused by other closely related components such as a dirty or failing mass air-flow sensor, a faulty throttle position sensor or potentially a vacuum leak. I would recommend having an expert from YourMechanic come to your location to diagnose and inspect your vehicle.
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