08-24-2017 | #1 |
Join Date: Jun 2016
Location: Prior lake
Posts: 65
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New fuel pump. Takes much longer to start
So I recently put in a new fuel pump in. Seemed pretty straight forward. Now it turns over for quite a bit longer before it starts.
Thoughts? |
08-24-2017 | #2 |
Join Date: Feb 2012
Location: Ledyard,CT
Posts: 8,230
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Re: New fuel pump. Takes much longer to start
Some of the new fuel pumps are coming out with defective hoses; from small leaks to in time splitting the full length of the hose.
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08-24-2017 | #3 |
Join Date: Nov 2007
Location: Squires (near Ava MO in the Mark Twain N'tl Forest) - Missouri
Posts: 6,493
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Re: New fuel pump. Takes much longer to start
One thing at a time: I'd suggest you'd first want to know the fuel pressure readings at the rail with the key ON, before turning the starter (to see if adequate fuel pressure is present), before hypothesizing further or raining parts on it.
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08-24-2017 | #4 | |
Join Date: Jun 2016
Location: Prior lake
Posts: 65
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Re: New fuel pump. Takes much longer to start
Quote:
Never done that before. I assume there's a video somewhere on how to do it? |
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08-24-2017 | #5 |
Join Date: Aug 2005
Location: Scottsdale, AZ
Posts: 2,452
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Re: New fuel pump. Takes much longer to start
When I start my car I turn key to on position, let pumps pressurize system then turn to start, hold key longer than a regular car to avoid backfire, after replacing both my pumps my car starts faster now than it did with old pumps
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08-25-2017 | #6 | |
Join Date: Nov 2007
Location: Squires (near Ava MO in the Mark Twain N'tl Forest) - Missouri
Posts: 6,493
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Re: New fuel pump. Takes much longer to start
Quote:
Turning the ignition switch to ON and pausing (as PhillipsLT5 described), you should see the pressure in the mid 40s (e.g., ~45± 2#). (And, BTW, after turning the switch OFF, the pressure should hold to a pound or two for 10-15 minutes or so. If if falls off faster, either a check-valve in one of the fuel pumps is bad, or there is one or more leaking injectors; neither is a good thing - especially if it is leaking injectors. But, that is getting further off topic!)
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08-25-2017 | #7 |
Join Date: May 2007
Location: Peoria, AZ
Posts: 9,155
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Re: New fuel pump. Takes much longer to start
How much longer ?
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08-25-2017 | #8 |
Join Date: Mar 2007
Location: Crystal Lake, IL
Posts: 7,193
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Re: New fuel pump. Takes much longer to start
Longer crank can sometimes mean the check valve is not working on a pump
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08-26-2017 | #9 |
Join Date: Jul 2010
Location: Woodstock, Ontario, Canada
Posts: 1,275
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Re: New fuel pump. Takes much longer to start
Cycle the key once to cycle the pump. That will pre pressurize the system before you engage the starter to crank the engine.
Since the new symptom occurred concurrently with a pump change, something in the pump or near the pump is letting pressure back into the tank. I agree with Lee on this one. The start of this video explains the potential issue. https://www.youtube.com/watch?v=5YLRtA_QHa8
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