First, I'd like to thank everyone for the previous advice on the engine stalling at low speeds and when in park. I cleaned the MAF sensor and no longer have that issue. Cost me about $8 for the cleaner.
My I-30 now has about 120K miles and so far since about the 80K mark I have changed all engine coils and spark plugs, cleaned the MAF and changed all O2 sensors. If I can get this last issue resolved, I think that I will be set for a little while.
Here is the final issue I am dealing with: In the morning, or after the car has set for 4-5 hours, there is basically nothing when I press the gas. Literally, I press the gas and the car decelerates and the RPM goes down. After I drive for a minute or two, all is well for the most part...though it still will hesitate a little when accelerating at highway speeds. It feels like I'm pressing the gas, but the gas can't get to the engine or something.
Any ideas? Are the fuel injectors clogged or something? I would appreciate any assistance.
Thanks,Jeremy
2000 I-30 Engine Sputter at Startup
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loystock
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Re: 2000 I-30 Engine Sputter at Startup (i30atl80)
Problem is most likely due to a failing fuel pump, dirty fuel filter and/or faulty fuel pressure regulator. You need to connect a Fuel Pressure Gauge downstream of the fuel filter to check the fuel pressure and leak-down. You can buy or rent a gauge from AutoZone. Harbor Freight sells it for @ $12 (not sure about current pricing).
To check the basic condition of the fuel pump, set Ignition Switch to ON (do not start). The fuel pump should run for about 5 secs. The fuel pump is mounted in the fuel tank and is accessible behind the rear seat, pax side. If the pump is noisy (it hums when running normally), the pump is on its last leg and needs replacement.
Before connecting a T-fitting to the fuel pressure gauge, ensure the fuel line is empty – FIRE HAZARD. With the engine running, pull out the fuse for the Fuel Pump and let the engine die. Crank the engine at least once to ensure the fuel line is empty.
Remove the Fuel Filter (mounted on firewall, besides brake booster). Blow air thru the fuel filter (in the direction of fuel flow). There should be low or no resistance at all if the filter is good. Otherwise, replace the filter.
To check the Fuel Pump output and Fuel Pressure Regulator, connect the Fuel Pressure Gauge and re-install the fuse. To verify, do the following:-set Ignition to ON (do not start) and check fuel pressure is @ 43 PSI (pump will automatically shutdown after 5 secs if Ignition is left in the ON position)-Start the engine - at Idle the fuel pressure is @ 34 PSI.-Turn OFF the engine - -fuel pressure drops to @ 30 PSI and should remain steady for several minutes. Then it will drop further to 20 PSI or less.
If the fuel pressure drops immediately after turning off the engine, the leak-down is bad and the regulator needs to be replaced. The Fuel Pressure Regulator is mounted on top of the engine, driver side.
The fuel injectors may be dirty. Use quality Fuel System Cleaner like Red Line SI-1 (@ $8) or BG44K (@ $18) every 6 months to keep fuel injectors clean as well as the combustion chamber intake valves, etc. I have used BG44K for a long time but switched to Red Line this year after they changed the BG formulation.
To check the basic condition of the fuel pump, set Ignition Switch to ON (do not start). The fuel pump should run for about 5 secs. The fuel pump is mounted in the fuel tank and is accessible behind the rear seat, pax side. If the pump is noisy (it hums when running normally), the pump is on its last leg and needs replacement.
Before connecting a T-fitting to the fuel pressure gauge, ensure the fuel line is empty – FIRE HAZARD. With the engine running, pull out the fuse for the Fuel Pump and let the engine die. Crank the engine at least once to ensure the fuel line is empty.
Remove the Fuel Filter (mounted on firewall, besides brake booster). Blow air thru the fuel filter (in the direction of fuel flow). There should be low or no resistance at all if the filter is good. Otherwise, replace the filter.
To check the Fuel Pump output and Fuel Pressure Regulator, connect the Fuel Pressure Gauge and re-install the fuse. To verify, do the following:-set Ignition to ON (do not start) and check fuel pressure is @ 43 PSI (pump will automatically shutdown after 5 secs if Ignition is left in the ON position)-Start the engine - at Idle the fuel pressure is @ 34 PSI.-Turn OFF the engine - -fuel pressure drops to @ 30 PSI and should remain steady for several minutes. Then it will drop further to 20 PSI or less.
If the fuel pressure drops immediately after turning off the engine, the leak-down is bad and the regulator needs to be replaced. The Fuel Pressure Regulator is mounted on top of the engine, driver side.
The fuel injectors may be dirty. Use quality Fuel System Cleaner like Red Line SI-1 (@ $8) or BG44K (@ $18) every 6 months to keep fuel injectors clean as well as the combustion chamber intake valves, etc. I have used BG44K for a long time but switched to Red Line this year after they changed the BG formulation.
Re: 2000 I-30 Engine Sputter at Startup (loystock)
Wow. Thanks for the detailed advice on diagnosis. I have a busy week and a busy weekend, so I probably won't get to this until the weekend of the 24th, but I will keep you posted and let you know the outcome of my testing. Hopefully it is just the fuel filter, but we shall see.