My car has trouble starting. I’ve had the spark plugs replaced and the gas pump checked but it still seems to have a lot of trouble firing up… battery is new and definitely not the issue…it constantly seems like the gas isn’t getting to the engine to fire. But the electronics say the pump is fine and it seems to run perfectly normal once running. Help me out guys! 
What electronics? How was the fuel pump tested? Have you had the electrical system checked (ie the starter too) to make sure that’s it’s a fuel problem? When the plugs were replaced, did you use the OEM plugs? Did the trouble starting start before or after you had the spark plugs replaced and the fuel pump checked?
I’m unaware of any electronics that can do this. Can you elaborate?
Same here, I said it to OP who said that originally…
Is there any pattern as to when it will not start? first thing in the morning, after short trips, after a long drive, in the rain etc.
It might be the fuel pressure is leaking down when the engine is off, so it takes some time for it to re-pressurize enough that it will start the next time. You need a fuel pressure test to have the ability to hold rail fuel pressure assessed. There’s check valve in the fuel pump ass’y that can fail and cause this for example. The symptom is cranks ok, but takes a lot of cranking to finally start, but then runs and performs fine as long as the engine remains on.
The next time it’s difficult to start the engine, turn the ignition switch on so the dash lights come on for two seconds, and then turn the ignition switch off.
Repeat this a half dozen times and then try starting the engine.
If the engine starts right up, it points to a problem with the anti drain-back valve on the fuel pump.
Tester
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Please clarify: when you try to start, does the engine turn over at its normal speed, but fail to actually start and run?
If so, Tester’s “key dance” is the thing to try. Each time the key is turned to Run (not all the way to Start) you may hear the fuel pump in the gas tank run for a few seconds, then turn off. When you turn the key to Off, then to Run, it should run again briefly. Each time, there is more fuel and fuel pressure brought up to the fuel injectors. When you turn the key all the way to Start, it may fire right up and run. Hope so. Let us know and good luck.
Hey everyone! Thanks for all of the interest. I’ll try to provide more information by the categories listed below
When does this typically happen?
- This seems to happen after running the car in hot weather for 20min or more. It almost seems like there is a sensor that identifies overheating and doesn’t allow the fuel pump to turn on. I’ve stopped to fill up with gas on long trips and it seems like I have to let the car cool down for 10-15min then it will fire up again.
The “Key Dance” Seems to work and I’ll add that a little pump of the gas peddle sometimes seems to help.
I tried turning the key to “Run” and actually opened the fuel tank to see if I could here any hum from the fuel pump…couldn’t hear anything. So my guess is that it’s the fuel pump or the sensor for the fuel pump.
The place I took it to said that their electronic diagnostic equipment said there were no issues with the car, but they found that my spark plugs were bad and that I had a little oil leaking into the area where the spark plugs fire. So they replaced the spark plugs replaced the seals on the engine into that area and it fired right up. I drove away happy to have the car running again. But the starting issue is still there. I’ve been doing the “Key Dance” and letting the car cool down now for over a week trying to figure out my next move. I’m leaning towards it being the fuel pump not working at all. Anyone have any other thoughts?
BTW Tester thanks for the suggestion of the anti drain-back valve. I think that might be part of the problem.
Thanks for the anti drain-back valve on the fuel pump. I’ll have my guys check that.
Thanks! That’s great help! I’ll have my guys check that!
If the fuel pump is not working at all, at times, the fuel pump relay, also called main relay, is suspect. It is probably under the dash board not far from the steering column. Many reports over the years of it not working esp. with hot interior temperatures. Not expensive, and some have repaired them by resoldering bad connections inside them.
You could also have a leaking injector. If you pump the gas pedal, that actually brings more air through the cylinders and helps clear an over-rich condition. Often a fuel system cleaner chemical in the gas will help fix a leaky injector. Car Talk guys used to recommend ones with Techron.
You have to take it back to the mechanic and have them test the pump properly.
This consists of them installing as fuel pump pressure gage on the test port on the fuel rail.
Then they can read if the fuel pressure is within spec’s. Then they will shut off the engine and see if pressure is maintained at the fuel rail. If the pressure drops, this means that the drain back valve is bad.
Yosemite
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