I will try my best to describe the problem:
When the car sits for quite a few hours it basically will try to fire up , but can take 4,5,6 seconds before it will actually start. It is a fast turn over just as if your car was going to start normally, but it just takes time. This is not a slow turn over as in a battery problem, or a very cold weather thick oil problem.
After the car starts the initial time, you can turn it off and start it and it fires right up.
When I turn the key to the on position, I can hear the Fuel Pump. I have tried doing this a few times in a row, but it doesn’t help the initial start.
This has been going on for about 8 months, and I have basically ignored the problem. The last few starts the same issue persisted except instead of firing up after 4,5,6 seconds it just shuts off. After this I turn the key over and it still fires right up.
Hope the explanation is clear and thanks for any insight!
I think your fuel pump is not keeping pressure. There is a one way valve that keeps the fuel from draining from the lines back into the tank when it sits. I think this valve if faulty.
When it does start…even for a second or two…the pump fills those lines.
You’ll need someone to test the fuel pressure and weather that pressure drops off much when the engine is shut down. It should maintain good pressure always, and if it drops much when shut down, you will need a new fuel pump.
Hi thanks for the reply, where is this valve located? I assume since you say I would need a new Fuel Pump that the valve is built into the pump?
Yes and I doubt that the valve is available separate or can be replaced on the unit.
Yosemite stole the words from me. It seems that you dont have the needed Fuel Pressure to start the car initially. Then once she is running…you build up normal pressure and can start up quickly afterward.
Yosemite is partially correct. The Job of MAINTAINING FUEL PRESSURE…DOES NOT Fall on the Fuel Pump…But on the Fuel Pressure Regulator Which is located somewhere at one end of the FUEL RAIL. The valves involved on the Fuel Rail to test fuel pressure is a simple Schrader valve and IS REPLACEABLE…
On the Fuel Rail you will have the FPR (Fuel Pressure Regulator) on one end of this Fuel Rail you will have the return line that runs back to the tank. The Fuel Rail is supposed to have pressurized fuel AT ALL TIMES that has built up from while the fuel pump was running… Either the FPR is leaky and is sending fuel back to the tank via the return line…or something else is causing the Fuel Rail to lose pressure while the vehicle sits for a little while…this can be the Fuel Pressure Test Nipple with the Schrader Valve. You need to check n see.
INSPECT your Fuel Rail for leaks… It can leak from the Regulator (Which will be an Internal leak back to the tank via the fuel return line)…This would be when the Regulator has gone bad and is not able to Hold Working Pressure for any length of time. Or the valve at the Pressure test nipple is not holding pressure.
You need to take a looksie at your FUEL RAIL and let us know what you see. Sometimes you can Spot OR SMELL the issue. Its PROBABLY A FAULTY FUEL PRESSURE REGULATOR…Kinda common issue. Let us know what you gots. When they fail…they let fuel leak back into the tank Pretty simple fix actually…
The next time you know it’s going to take long to get the engine started, cycle the ignition key on and off a half dozen times and then try starting the engine. If the engine starts right up the problem is with the anti drain-back valve on the fuel pump.
How this valve works is, once the fuel pump shuts off, the valve will hold what is called residual fuel pressure in the fuel system. This residual fuel pressure will slowly bleed off over 15 minutes to half hour until there’s no fuel pressure in the system. But the valve is suppose to prevent any fuel in the fuel rail(s) and line from draining back into the fuel tank. If the valve doesn’t prevent this from happening, it takes longer for the fuel pump to refill the fuel line and fuel rail(s) and build the proper fuel pressure so the engine can start.
To check if this is the problem, a fuel pressure gauge is connected to the fuel rail. The ignition switch is turned to the run position to run the fuel pump and then shut off. Then the gauge is observed to see how quickly the residual fuel pressure bleeds off. If the gauge immediately drops to 0 PSI, the anti drain-back valve on the fuel pump is no longer working. And the fuel pump requires replacement.
Yes I would go with what Tester and Yosemite say. I thought the valve that held pressure inside the rail was on the rail itself. I think Tester and Yosemite have me corrected and the valve actually IS on or associated with the pump. These guys have it correct…I’ve made the proper mental notes for next time
OK thanks for your replies, I did have to replace the Fuel Pressure Regulator as it was leaking gas, but the bad thing is this is my wife’s car and she doesn’t always make me aware of issues when they first arrive. So at this point I can’t remember if this was happening before the FPR was replaced.
On a side note Advance wants $200 to rent the Fuel Pressure Gauges(ha ha).
To “tester” I have cycled this on and off a few times in the past and the problem still existed. Tomorrow morning I will cycle on 7-8 times to see what happens and report back here.
I cycled the pump on 8 times today and the car was still slow to start.
I was also able to get a fuel pressure gauge today. When turned to the on position the gauge shoots up to about 40 psi and then bleeds out to 0 within about 10 seconds.
I then clamped the return line closed(with the key in the on position) and the gauge held at 60 psi, with the clamp on and engine running it held at about 80 psi.
So, I guess now I am confused as to why the 8 time cycle didn’t start the car immediately.
In old cars that was an indication of bad timing. Might be a bad injector or fuel pressure regulator or fuel pump, my wag
Sounds as though it may be something as simple, inexpensive, and easy to fix as the fuel regulator which sits at the top of your car’s engine and is very easy to remove and replace with simple hand-tools. A shade-tree mechanic can do the job of replacing it in about 20 minutes and the part can be obtained at Autozone.
Friz, you need to read all the posts. OP has already replaced the fuel regulator.
I replaced the fuel regulator quite a few months ago because it was leaking gas. It’s been so long that I don’t know if the slow start was before or after the replacement. I have read online about quite a few defective brand new regulators.
Can anyone explain the results of clamping of the return line?. When I clamped off the return line and the pressure held at 60psi with the key in the on position.
My main question here is if the Pump Check Valve was bad would the pressure had leaked back the supply line?
If I understand correctly the fuel pressure tests you did, that sounds like a problem with the fuel pressure regulator. The pressure shouldn’t bleed back down in 10 seconds after turning the pump off, but since it doesn’t bleed down if the return hose is clamped, then it can’t be the pump check valve that is leaking. If it was the pump check valve, it would bleed down either way.
I don’t have any experience with your make/model, but from what you are saying, the fuel delivery system is configured like my Corolla. The pressurized fuel from the pump goes to the FPR, which has a rubber diaphragm/spring ass’y in it, so it holds a constant pressure at the rail. Any extra fuel from the pump not needed to maintain that rail pressure is sent back to the tank through a passageway in the FPR, then to the return hose.
I realize you’ve had that part replaced, but it seems the new part may have failed as well. One thing your shop could do, there should be a vacuum hose from the FPR to the intake manifold. Remove that hose at the FPR and see if there is any gasoline inside the hose or inside the port the hose connects to. If so, that’s a sign the FPR is bad.