This relates to a lean fuel condition which can be caused by many different things such as:
Intake air leaks Faulty front heated oxygen sensor Ignition misfiring Faulty fuel injectors Exhaust gas leaks Incorrect fuel pressure Lack of fuel...
Not exact matches
But if the raised
air intake leaks, the cylinders will draw in water; avoiding engine carnage would probably be unavoidable and we'd be stuck waiting for the tide to wane before being towed, red - faced, to safety.
The Soapy Water Test has you putting water in a spray gun with a bit of soap on areas of the
intake system that are suspected
air leak points.
Two
leaks were detected, the first was in the
air intake hose, and the was coming from the throttle body.
But check all Vacuum hoses on eng especially on computer control EGR control Valve A big
leak or blown hose will cause the DPE code, Plus if hose blown (melted) will cause stalling, rough idle and smell through the
air intake duct..
The question is here: Diagnosing P0171 2007 Toyota Corolla I only have a OBD2 reader, I just bought a scanner, which should come on Monday but when I was looking around my engine for
leaks and such, I saw a little crack where the PCV pipe connects with the
air intake pipe.
If the engine continues to run after blocking the
intake, this is a clear indication that the engine is drawing
air from an alternative source, i.e. a
leak.
Since the
intake manifold pressure is directly measured to calculate the
intake air volume and decide the amount of fuel to inject, a vacuum
leak theoretically can not contribute to a lean condition like this.
, condition of various sensors (
air, lambda),
intake leaks
An
intake manifold
air leak is therefore most likely.
Remember you'll need new gaskets to do this or your new engine will have plenty of issues (like vacuum
leaks in the
intake which will allow unmetered
air into the
intake system, and exhaust
leaks which will allow
air into the exhaust track allowing for really crappy gas mileage.).
You might also check vacuum lines and
intake manifold gasket for
air leaks.
Start a vacuum -
leak smoking expedition by plugging up any obvious potential ports in the
intake manifold, starting with the inlet to the throttle body from the
air cleaner.
A vacuum
leak from items like a broken
air intake boot, broken / disconnected vacuum lines, or a
leaking intake manifold gasket can lean out the
air / fuel mixture or disturb
intake airflow enough to...
Stalling at idle could be due to a faulty mass airflow sensor, faulty camshaft or crankshaft position sensors, worn spark plugs, wires or defective ignition coil (s), inadequate fuel delivery or pressure (clogged fuel filter, injectors, faulty fuel pump or pump circuit), contaminated or old gasoline, defective throttle position sensor, faulty idle
air control valve,
leaks in the EGR system,
intake vacuum
leaks, and so forth.
This could be anything from a mechanical issue (low oil pressure,
intake air system
leak, etc.) to an electrical problem (throttle position sensor, oxygen sensors, etc.).
An
intake gasket
leak would allow unmeasured
air into the
intake and create a lean condition, not an overheating issue.
Hi - I suspect your rough idling is an
air leak (loose hose or crack in the
air intake), or dirty idle
air control valve.
Fuel related misfires can be caused by many different things such as low fuel pressure, faulty or dirty fuel injectors, a faulty O2 sensor, a dirty or failing mass
air - flow sensor, a faulty or dirty idle
air control valve or a vacuum or
intake leak.
If you've just cleaned the throttle body but now have an MIL on with DTC P2279 (
intake air system
leak), MIL on with P0507 (idle control system rpm higher than expected) and / or a fluctuating idle, it's likely that the throttle plate is now in a different position from the one that the ECM / PCM had learned.
Check carefully under the hood to be sure there are no
air large
air leaks in the
intake system, such as the big boot at the throttle body or any other large vacuum hoses.
One thing that can cause that is an
air leak that enables
air to enter the
intake system without passing first...
A dirty throttle body (which you have already checked), a dirty idle
air control valve, a failed throttle position sensor, an
air leak in the
intake (loose or split hose,...
If there are
air leaks in the
air induction system (e.g., the snorkel) that allow unmetered
air into the
intake, that circumstance could cause the two codes, P0171 and P0174.
In a more technical jargon, vacuum or
intake leaks are called «unmetered
air», as the
air enters the
intake system through a damage
intake boot or other
leak is not metered by the mass
air flow sensor and therefore the the engine computer can not calculate the amount of fuel injected properly, causing the engine to run «lean».
An
air leak anywhere between the engine
intake and the air filter is usually called vacuum or Intake
intake and the
air filter is usually called vacuum or
IntakeIntake leak.
«For under $ 100 in most markets, you can get your system examined by a professional who can spot
air duct
leaks,
intake blockages, mechanical failings, electronic failings and more.