Allpar Forums banner

1 - 4 of 4 Posts

·
Registered
Joined
·
2 Posts
Discussion Starter #1
My son's 91 New Yorker is having problems staying running when coming to a stop. It only does it occasionally, most times it will start right back up, but a couple of times he has had to wait 2-3 min to get it to start again. Sometimes he has to press on accellerator to get it to start again. Have checked fuel pressure, seems to be within normal specs. Changed crank sensor, and fuel filter. Had battery disconnected to chang power steering pump 2 weeks ago, and went through re-learn procedure. I checked codes with key on-off sequence, and only code that comes up is code 12, memory standby power receintly lost. I have read that this code should go away after12-15 starts. It has been many more than that and code is still there.
Please help!!
 

·
Super Moderator
Joined
·
21,351 Posts
Welcome to Allpar.The fault code 12 is usually the code that many fault code reads start out with, then you get your real codes and the sequence ends with a 55. It may be normal.
If you suspect that you are losing battery memory back-up to the PCM, see if your scan tool shows 'starts since set'. A 0 starts since set would confirm that the battery supply to the PCM is being truly interrupted.
Which engine? It sounds like a possible rich or lean die at idle. Make sure that the throttle body blade and bore are clean and free of carbon. Do not adjust the minimum air screw, the PCM controls idle speed. The AIS (and other components) can act up and not set a fault code. It is always nice and easy when they do.
Fuel pressure regulator vacuum diaphragms can rupture and raw fuel will then be sucked into the intake manifold through the vacuum hose and cause a rich condition. If you pull the vacuum hose and the inside is wet with gas, this is a leaking regulator. Replace it. This is one of those 'invisible' fuel leaks.
 

·
Registered
Joined
·
2 Posts
Discussion Starter #3
Sorry I forgot to say what engine. It is the 3.3 V6 engine. I have checked the vacuum hose at pressure regulator and am not seeing any gas. I went through and checked all ground locations that I could see and cleaned them. Also checked for vacuum leaks and am not seeing anything obvious. I tested my TPS according to my Chilton's manual, and all voltages seem to be within range. I do not have a vacuume pump to check the MAP sensor.
This seems to be kind of an odd problem, because it went from a problem with dying under acceleration to a problem with dying at stops.
 

·
Super Moderator
Joined
·
21,351 Posts
If the idle improves by pulling off a vacuum hose (i.e.-PCV hose), that could confirm a rich condition. Fuel pressure OK?
How do the spark plug tips look? Black would be rich. Many times they will tell a story. Having to hold down the gas pedal to start sounds rich.
An ignition problem would be likely evident whatever the engine speed. Is this worse warm or cold?
Any reaction by wiggling wires harnesses?
 
1 - 4 of 4 Posts
Top