Glanzone1

I've owned this car since new. It's been a very reliable car but with 205k miles some things are starting to pop up. Currently it will start right up but not continue to stay running. I'm not getting any codes from the OBD system but I went ahead and changed the crank position sensor anyway. That didn't help, so I'm thinking about looking at the fuel system ie. relay and fuel pump. I'm going in this direction because before while driving up hills and demanding more throttle from it, the car would stumble a bit and sometimes would take a few seconds to catch up to the throttle input. I've read several of the threads on the site about similar issues so I checked those things as well with no problems from those systems, ie..immobilizer, battery, alternator, and.key fob. So back to the fuel system, is there diagram to show which relay is for the fuel pump on the main power panel? Also, if it is a fuel pump by chance is there a way to check it first other than by sound? Thanks for any input in this issue.

DaIll1

I'd start with adding an injector cleaner to the fuel. When I bought my new pump (to add a high flow) the parts guy said it's unusual for an RDX to need one.

Glanzone1

I will add fuel injector cleaner to my next tank but I don't believe this is the source of my problem. I'm going to test the fuel pressure at a fuel line just before the injector rail. As I'm saying this I was wondering if there is a special tool needed for the removal of fuel line couplings just before the fuel rail. Any input is appreciated.

Glanzone1

I was able to put a fuel pressure gauge in line at the fuel rail and the pump is putting out 52 psi. No leaks through the injectors. While the car runs for 3-4 seconds pump maintains 35-38 psi. Still starts every time quickly but dies after 3-5 seconds.

DaIll1

Air, fuel, spark are the 3 things involved. Sounds like air and fuel are good. Perhaps the ECU is getting bad info and making stupid decisions. You may want to check the sensors. Have you cleaned your MAF sensor?