Foxtrot Posted January 24, 2023 Share Posted January 24, 2023 Hello, I need a little help in figuring out what could be causing this issue. A few days ago, I parked my Reatta in my garage like I usually do, and the next morning it cranked right up, ran for about 4 seconds, then the rpm's dropped lower and lower until it stalled out. I tried starting it, and it would just crank and sputter but not start. I tested the fuel pump fuse, the relay, and they're all working. Since I have no way to power the primer, I decided to check whether the pump is getting power or not with a multimeter. When I turned the key, it would read 12V for 2 seconds, then back to 0. To my knowledge this is normal operation. I decided to change out the fuel pump, then tested the old one with a car battery, and lo and behold, it worked. Odd, but I guess I'll keep it for backup. Car worked just fine after that. Then, one morning about 2 days later, I tried starting it, cranked right up, ran for about 4 seconds then it stalled. I'm right back to where I started; good relay, good fuse, and the pump is still getting power but I don't hear it run. Was it just a defective pump? are they getting clogged? is there a short somewhere? I'm completely lost here. Any help is greatly appreciated. Link to comment Share on other sites More sharing options...
Ronnie Posted January 24, 2023 Share Posted January 24, 2023 45 minutes ago, Foxtrot said: When I turned the key, it would read 12V for 2 seconds, then back to 0. To my knowledge this is normal operation. That's normal. Are you putting pressure gauge on the fuel rail when it won't start to see if the pump is building enough pressure? Instructions for testing in the How-to guides here on ROJ. 1 Link to comment Share on other sites More sharing options...
2seater Posted January 24, 2023 Share Posted January 24, 2023 As per above the fuel pressure is important. Was the fuel pump installed using the old pulsator or was a hose installed instead? If a hose was installed, was it hose clamped? The pressure check will tell the tail. Also, pull the vacuum hose from the pressure regulator on the front of the fuel rail and check for fuel getting through the diaphragm. It should be bone dry. Link to comment Share on other sites More sharing options...
Padgett Posted January 24, 2023 Share Posted January 24, 2023 Was the new pump a Delco ? Did you replace the filter on the driver's frame rail ? What is the fuel rail pressure doing ? Need 35-40 psi to idle. Link to comment Share on other sites More sharing options...
Foxtrot Posted January 25, 2023 Topic Author Share Posted January 25, 2023 28 minutes ago, Padgett said: Was the new pump a Delco ? Unfortunately, due to time constraints and budget, I was only able to find a NAPA pump. I've heard favorable reviews from people who've bought from them so I thought it'd be okay. Link to comment Share on other sites More sharing options...
Foxtrot Posted January 25, 2023 Topic Author Share Posted January 25, 2023 (edited) 1 hour ago, 2seater said: As per above the fuel pressure is important. Was the fuel pump installed using the old pulsator or was a hose installed instead? If a hose was installed, was it hose clamped? The pressure check will tell the tail. Also, pull the vacuum hose from the pressure regulator on the front of the fuel rail and check for fuel getting through the diaphragm. It should be bone dry. I used a new strainer, and the old pulsator. I havent changed out the fuel filter up on the fuel rail, though. I guess I should check that too. I unfortunately don't have a fuel pressure testing device but that's my next step. I should mention the engine exhibits every symptom of fuel starvation, and the pumps motor isn't audible at all. It usually is. I think it just isn't running whatsoever, but I could be wrong. I'll check the vacuum hose when I get home Edited January 25, 2023 by Foxtrot Link to comment Share on other sites More sharing options...
rogold Posted January 25, 2023 Share Posted January 25, 2023 Maybe check the fuel filter too. Link to comment Share on other sites More sharing options...
2seater Posted January 25, 2023 Share Posted January 25, 2023 (edited) 3 hours ago, Foxtrot said: I used a new strainer, and the old pulsator. I havent changed out the fuel filter up on the fuel rail, though. I guess I should check that too. I unfortunately don't have a fuel pressure testing device but that's my next step. I should mention the engine exhibits every symptom of fuel starvation, and the pumps motor isn't audible at all. It usually is. I think it just isn't running whatsoever, but I could be wrong. I'll check the vacuum hose when I get home I suspect that the pulsator connection leaks causing the fuel pressure to immediately disappear from the priming shot. A squirt of fuel into the intake may allow the engine to start . A fuel pressure test will tell the tail immediately. I had this happen on the car my son now has. The fuel pump had been replaced at some point and the short substitute hose was installed but it was not clamped allowing it to leak the pressure away after it accumulated some miles. If the new pump is the turbine type it may be quieter so not as obvious. Edited January 25, 2023 by 2seater 2 1 Link to comment Share on other sites More sharing options...
Foxtrot Posted January 25, 2023 Topic Author Share Posted January 25, 2023 14 hours ago, 2seater said: If the new pump is the turbine type it may be quieter so not as obvious. Forgot to mention, I appreciate the replies. Last I checked, the pump is piston driven, as I'm trying to keep the car as stock as possible. But, quick question: Wouldn't the pump's motor still be at least somewhat audible even if the fuel isn't flowing? (assuming it's functional and powered) Link to comment Share on other sites More sharing options...
Ronnie Posted January 25, 2023 Share Posted January 25, 2023 Go to AutoZone or Advance, borrow a fuel pressure tester and check the pressure. Take the guesswork out of it so we can help you get your car going. 1 Link to comment Share on other sites More sharing options...
Foxtrot Posted February 14, 2023 Topic Author Share Posted February 14, 2023 (edited) On 1/25/2023 at 12:59 PM, Ronnie said: Go to AutoZone or Advance, borrow a fuel pressure tester and check the pressure. Take the guesswork out of it so we can help you get your car going. I've confirmed there is 0 pressure at the fuel rail. The pump is not audible at all, but the priming connector reads 12 volts for 2 seconds when ignition is turned on. The pump is brand new and works if removed and directly connected to a battery. I tried buying a new battery (since the one I had was starting to go out anyway) and checked the ground junction to the body and behind the battery box. No difference. Edited February 14, 2023 by Foxtrot Link to comment Share on other sites More sharing options...
Ronnie Posted February 14, 2023 Share Posted February 14, 2023 21 minutes ago, Foxtrot said: the priming connector reads 12 volts for 2 seconds when ignition is turned on. That is normal reading on the prime/test connector each time you turn the key to the run position. It will have 12 volts continuously once the engine starts. 23 minutes ago, Foxtrot said: The pump is brand new and works if removed and directly connected to a battery. I think you have proved the pump is good. Have you tried connecting 12 volts from the battery to the prime/test connector? The pump should start running continuously when you do that and you should have pressure on the fuel rail. If it doesn't run like that, check to see if you have 12 volts at the pump connector at the tank. Link to comment Share on other sites More sharing options...
Foxtrot Posted February 14, 2023 Topic Author Share Posted February 14, 2023 1 minute ago, Ronnie said: I think you have proved the pump is good. Have you tried connecting 12 volts from the battery to the prime/test connector? Would it be safe to run a wire directly from the battery to the prime connector with no fuse? I don't want to accidentally fry anything. Link to comment Share on other sites More sharing options...
Ronnie Posted February 14, 2023 Share Posted February 14, 2023 Yes, as long as you don't short the wire out while doing it. That is what the prime connector is for. They did that at the factory to prime the fuel system for the first time. 1 Link to comment Share on other sites More sharing options...
Foxtrot Posted February 14, 2023 Topic Author Share Posted February 14, 2023 6 minutes ago, Ronnie said: Yes, as long as you don't short the wire out while doing it. That is what the prime connector is for. They did that at the factory to prime the fuel system for the first time. Will report back once I get home and do it. Praying to hear that annoying little hum again. 1 1 Link to comment Share on other sites More sharing options...
Padgett Posted February 15, 2023 Share Posted February 15, 2023 Hum and no pressure: clogged fuel filter, sock, or line. Link to comment Share on other sites More sharing options...
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