Intermitant popping and backfiring on startup after new fuel system.
08-20-2009, 11:16 AM
#1
Intermitant popping and backfiring on startup after new fuel system. A couple of months ago I switched over to a boost referenced fuel pressure regulator( BRFPR ) and external magnafuel pump. Ever since I switched over, the car has acted like it has a bad cam sensor. All the symptoms are identical. Sometimes it fires right up and sometimes it wont catch. Key off. Try it again and then it'll backfire a little thru the exhaust or it'll start right up. Doesn't mater if it's cold or hot. Doesn't mater how long it sits either. We checked the wiring to the cam sensor just to make sure and it seemed ok.
The only thing that I can come up with is that the fuel pressure is at 60# with the key on and the car off (no vacuum). As soon as there is vacuum, the pressures drops to 45#. The car is tuned to idle at 45#. Am I maybe getting too much fuel at start up and flooding it every now and then? Is this a common issue with these setups? It's my first one like this. Or do I need to go back and take a hrader look at the cam sensor again?
The only thing that I can come up with is that the fuel pressure is at 60# with the key on and the car off (no vacuum). As soon as there is vacuum, the pressures drops to 45#. The car is tuned to idle at 45#. Am I maybe getting too much fuel at start up and flooding it every now and then? Is this a common issue with these setups? It's my first one like this. Or do I need to go back and take a hrader look at the cam sensor again?
