go my Pontiac last night
- Thread starter lilredpon
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the pump is supposed to run when the engine is running you may have a bad regulator
http://www.fierostore.com/Tech/Default.aspx?Id=423
http://www.fierostore.com/Tech/Default.aspx?Id=423
cammerjeff
Well-known member
I am Assuming a 1984 2.5 TBI engine.
Most of the time excessive fuel is due to a high MAP signal to the ECM. Depending on the equipment, it could be due to a severe vacuum leak, leaking EGR (causes the symptoms above, runs ok, but has bad idle), or a bad MAP sensor. Thinking back, the PCV is less likely as this would be similar to opening the throttle with SD. It would cause a high idle. The EGR is definatly suspect if the problem only appears at idle and is sporatic. The valve can be blocked open by coke, causing a lousy idle.
I would 1st check for Vacuum leaks and repair any found, check around the throttle body base plate, any old Vacuum lines (I would just replace all the Vacuum lines as they are 30 years old now) If that does not help I would remove the EGR valve and check that it operates when removed by applying Vacuum to the port. And Clean any coke build up from both the mounting surface and the Valve. Replace the Valve if it does not operate when vacuum is applied.
If those 2 things do not help, I would replace the MAP sensor.
Most of the time excessive fuel is due to a high MAP signal to the ECM. Depending on the equipment, it could be due to a severe vacuum leak, leaking EGR (causes the symptoms above, runs ok, but has bad idle), or a bad MAP sensor. Thinking back, the PCV is less likely as this would be similar to opening the throttle with SD. It would cause a high idle. The EGR is definatly suspect if the problem only appears at idle and is sporatic. The valve can be blocked open by coke, causing a lousy idle.
I would 1st check for Vacuum leaks and repair any found, check around the throttle body base plate, any old Vacuum lines (I would just replace all the Vacuum lines as they are 30 years old now) If that does not help I would remove the EGR valve and check that it operates when removed by applying Vacuum to the port. And Clean any coke build up from both the mounting surface and the Valve. Replace the Valve if it does not operate when vacuum is applied.
If those 2 things do not help, I would replace the MAP sensor.