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94 E420 new fuel pumps filter regulator plugs and wires. Idles then dies. Fuel pressure slowly exiting.

Posted by brucestelly on


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  • 14 Answers

SOURCE: 1992 gmc chevy 350 wont idle when warm

This could be a number of things but i think that your problem sounds like a vacuum leak or an EGR problem. Try listening for leaks and try un-plugging the EGR solenoid valve one time.

Posted on Apr 17, 2009



  • 169 Answers

SOURCE: 91 Jeep wrangler New everything idles rough, no Power then dies

you check for miss how is compression

Posted on Aug 29, 2009


daniel hendrickson

  • 1922 Answers

SOURCE: 94 toyota camry dies at low idle. replaced plugs,

replace the 02 sensor or the egr valve in the intake manifold needs replace or cleanout and is carboned up

Posted on Oct 11, 2009


Jeffrey Turcotte

  • 8984 Answers

SOURCE: 1999 olds 88. I

recommend you check your MAP sensor. You will need a voltmeter.
If you don't have a vacuum gage, just use your mouth to pull a vacuum on the hose and see if the voltage drops when you do.
Let me know if you have questions.

OPERATION The Manifold Absolute Pressure (MAP) sensor, used on 1996-99 vehicles, measures the changes in intake manifold pressure which result from engine load/speed changes, and converts this information to a voltage output. The MAP sensor reading is the opposite of a vacuum gauge reading: when manifold pressure is high, MAP sensor value is high and vacuum is low. A MAP sensor will produce a low output on engine coast-down with a closed throttle while a wide open throttle will produce a high output. The high output is produced because the pressure inside the manifold is the same as outside the manifold, so 100 percent of the outside air pressure is measured.
The MAP sensor is also used to measure barometric pressure under certain conditions, which allows the PCM to automatically adjust for different altitudes.
The MAP sensor changes the 5 volt signal supplied by the PCM, which reads the change and uses the information to control fuel delivery and ignition timing.

TESTING See Figures 1 and 2

  1. Visually check the connector, making sure it is properly connected and that all of its terminals are straight, tight and free of corrosion.
  2. With the ignition ON , check the voltage between terminals A and B (probe the back of the connector to connect to these wires). It should be above 4 volts. Apply 15 in. Hg of vacuum at the MAP vacuum port and check the voltage again. The voltage should be 2 volts now.


Fig. Fig. 1: Manifold Absolute Pressure (MAP) sensor circuit
When pumping up and releasing the vacuum, check to make sure the voltage readings are smooth. When applying vacuum to the sensor, the change in voltage should happen instantly. A slow change in voltage could point to a faulty sensor.


Fig. Fig. 2: MAP sensor voltage specifications

  1. If the sensor voltage is not within specification, check for a 5 volt reference at terminal C. If the reference signal is found, the sensor is faulty.
  2. If the sensor and circuits are functional, the PCM may be faulty.


3.8L (VIN K) Engine
See Figure 4
On these engines, the MAP sensor is mounted to the PCV valve cover.

  1. Disconnect the negative battery cable.
  2. Detach the MAP sensor electrical connector.
  3. Carefully bend the locking tabs holding the MAP sensor to the PCV valve cover, just enough to remove the MAP sensor.
  4. Pull the MAP sensor straight out of the PCV valve cover.

Fig. Fig. 4: On the 3.8L (VIN K) engine, the MAP sensor (1) is mounted in the PCV valve cover (2)

To install:

  1. Make sure that the seal is installed on the MAP sensor and that it is not damaged.
  2. Position and install the MAP sensor to the PCV valve cover. Make sure the locking tabs engage to hold the sensor to the cover.
  3. Attach the sensor electrical connector.
  4. Connect the negative battery cable.

Posted on Nov 27, 2010


Ronnie Meister

  • 2 Answers


1998 ford escort sport engine started making a tapping noise and engine light started flashing. Had oil and water at normal level.
Car has 110,000 miles. Been serviced regularly!

Posted on Mar 30, 2011

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