Helle,

I was told to do a fuel pressure drop test to see if the to see if the injectors are leaking down. Can anyone tell me how this is done?

Thanks,

Bill

 

I think they're telling you to (temporarily at least) install a fuel pressure gauge so that you can watch how long it takes for the fuel pressure to drop after the pump shuts off. The assumption is that if the pressure drops off too fast one or more injectors are leaking, or bad regulator, leaking hose, etc.

Find F-96 in the '93 manual at www.iluvmyrx7.com/ for instructions on installing a pressure gauge. If you splice a 'T' fitting into the fuel line with a 100-PSI gauge attached you can then read the fuel pressure for testing. After you're through just remove the gauge and plug the fitting, or if you get a quality gauge you can leave it installed, but you may need to support the added weight of the gauge using tie-rap or something.

Be sure and follow manual's precautions on releasing the fuel pressure before you start, and be careful about any sparks or flames.

Also, if you find that your injectors are leaking, consider trying several applications of a good quality injector cleaner before just pulling them out for service. It still may be required, but if the cleaner works its a lot less expensive in both time and money.