JustAnswer > Car
Ask A Question|Register|Login|Help
JustAnswer

Car

Ask a Car Question, Get an Answer ASAP!

Have your own Car question?

35 Auto Mechanics are Online Now
characters left:
Not a Car Question?

Related Car Topics:

  • Car
  • ,
  • Low
  • ,
  • Maf
  • ,
  • Lt1
  • ,
  • Pcm
  • ,
  • Set
  • ,
  • Wet
  • ,
  • Code
  • ,
  • Flow
  • ,
  • Fuel
Bookmark and Share

Question

No Comment Added

Submitted: 481 days and 20 hours ago.
Category: Car
Value: $9
Status: CLOSED
+
Read More

Optional Information

Optional Information:
1997 Pontiac formula LT1 V8

Accepted Answer

XXXXXXXXX,

The LT1's had a common problem with the fuel pressure regulator diaphram going bad. I would start there by pulling the vacuum line to the regulator and checking for raw fuel in the line. If the line is wet inside with fuel, replace the regulator.

Check fuel pressure. Hook a pressure gage to the schrader valve on the fuel rail and start the car. Pressure should be 41-47lbs. If it is low and the fuel filter has not been changed in a while replace it and recheck pressure.

The Mass Airflow Sensor is another place to check but should set a code in the PCM which would turn on the check engine light. You can try unplugging it to see if the car will respond. If the engine will respond with the MAF disconnected, replace it. Also check the hose that runs from the mass air flow sensor to the throttle body for any leaks. Holes, tears, loose clamps. Anything that will allow air to enter the engine after the mass air flow sensor will be unmetered air that cannot be compensated for by the PCM and will cause stalling.

Lastly, check for vacuum leaks. Lines and manifold gaskets leaking will cause a lean condition and stall the engine. A vacuum gage is a good cheap tool to use for checking. Hook the gage to a manifold vacuum port. Normal vacuum for idle should be around 50hg.

The fuel pressure regulator is on the fuel rail that the injectors connect to and will have a single vacuum line running to it.

 

 

 

Shawn



Edited by LSx Tech Shawn on 7/28/2008 at 1:08 AM

Picture
Expert: Shawn
Pos. Feedback: 100.0 %
Accepts: 
Answered: 7/28/2008

ASE Certified Technician

PA Certified Inspection emissions, ASE Brakes Suspension, Lead diagnostic Tech.20 years exp

+
Read More

Related Car Questions

  • Why does the axle make a clicking sound when I make full ...
  • How much would it cost to replace the front bumper ...
  • I have a 2002 Jeep Grand Cherokee. Sometimes it shakes ...
  • how do i replace the neutral safety switch on a 1996 suburba...
  • how does the rear caliper compress on a 1999 infinity ...
  • How do I recharge a BMW Z3 ignition key??
  • How do i change spark plugs on a 1996 vw jetta?
  • Electrical Problem please help



Disclaimer: Information in questions, answers, and other posts on this site ("Posts") comes from individual users, not JustAnswer; JustAnswer is not responsible for Posts. Posts are for general information, are not intended to substitute for informed professional advice (medical, legal, veterinary, financial, etc.), or to establish a professional-client relationship. The site and services are provided "as is" with no warranty or representations by JustAnswer regarding the qualifications of Experts. To see what credentials have been verified by a third-party service, please click on the "Verified" symbol in some Experts' profiles. JustAnswer is not intended or designed for EMERGENCY questions which should be directed immediately by telephone or in-person to qualified professionals.
Question List | Become an Expert | Terms of Service | Security & Privacy | About Us
© 2003-2009 JustAnswer Corp.