280Z Fuel Pressure Regulator Question

[DaleMX]

Is the Pressure on the injectors controled by vacuum? If so then what is the pressure range?

 

The reason I ask is at idle I am really rich and I am having vacuum problems.

 

Thanks for any help,

Dale

[Guest bastaad525]

Yes, the FPR adjusts fuel pressure based on vacuum/boost. The more vacuum there is present in the intake manifold, the more fuel is allowed to bypass the FPR, resulting in less pressure. Being really rich at idle can be caused by a lot of things. If you do suspect fuel pressure, it's very cheap and easy to set up an inline pressure gauge. It's one way to know a lot more about things your car is or might be doing. The parts can be had for all of $10-15 and installed in less than 30 mins easy. Here is a pic, it's in the lower right hand corner coming off the fuel filter... not the best pic, sorry but at least you can get an idea:

 

 

This was made with common cheap parts from Home Depot.

 

This will tell you right away if you're running rich because of problems with fuel pressure.... however, I usually find whenever my car starts acting up running badly, it's almost always something electrical with the EFI.

[DaleMX]

Thanks, I thought so. I have so many vacuum leaks. The car I got has not run in 10 years so all the vacuum hoses are brittle and cracked. Also some idiot must have worked on the injectors because at least 3 of them are missing the seals and sucking air. I've parked the car until I can get the leaks and seals fixed. Also there was no thermostat, and he has a wire run to the positive battery post that will cause the car to not run if it is disconnected. All the fuseable links have been replaced with wires. There was no air cleaner. Ahh, the joys of used car buying. The cars body is in good shape, thats why I got it.