how do you diagnose a bad fuel pump
Asked by steelhorse84 Feb 27, 2015 at 11:51 AM about the 2001 Ford F-150 Lariat Crew Cab 4WD SB
Question type: Maintenance & Repair
I have a 2001 F150 supper crew 4x4 that will start fine and the next time will just turn
over and over. I can cycle the ignition 3 or 4 times and it will crank and run great. This
will last a day or 2 and then it will do it again. I can recycle the ignition 2 or 3 times
and it will crank and run. It has been doing this a couple months but is now happening
more frequently I don't want to be somewhere andget stranded so I am looking for what
this may be. I am kinda thinking it is the fuel pump going out. Any help we be greatly
appreciated.
4 Answers
This could be either fuel or electrical, and that just occurred to me I am stating the obvious. What I mean is there are so many things possible, too much guesswork...maybe the anti-theft immobilizer acting up, some sensor sending no or wrong signals to the PCM. I suggest an OBDII scan, some parts houses will do it free. But if you do that, have it scanned, don't buy the firt thing the guy tells you, some know what they are doing and some not. Electrical parts can not be returned if you buy a part you don't need, and to avoid that, get the codes, they begin with a P and have four numbers. Bring the codes back here and post them and myself or somebody will be happy to help at leat point you in the right direction. OR, do a Google search "Ford OBDII PXXX" and you will get a page of sites that have causes and solutions. http://www.obd-codes.com is good and also http://engine-codes.com
I forgot to add the even if your CEL Check Engine Light is not on it still may have thrown a code If you do get a code, put it in a new question so we will know, and not miss it ------- For example if you get a P0230 means bad circuit, no power to fuel pump, P1233 is related to fuel pump..but remember these are only examples ..AND you do have a 4.6 engine right?
migration_lilwrench answered 9 years ago
I agree with FordNut, to many possibles. check with Ford (on line) and see if there is a recall on that fuel filter. Just remember the codes only point you in the general direction. A lot of systems cause a problem code. You or a mechanic will have to test,diagnose,fix what ever is up stream of the code.
It may just be a bad fuel filter. Try to change the filter. It is an easy and cheap thing to do. Usually located undrethe gas line. When it happens, try to just turn the ignition switch on , but not all the way..Have someone listen at the gas cap(take it off), they should hear the fuel pump turn over for about 2 seconds. Also when it happends , try to spray some starter fluid into the throttle, if it runs, you will confirm a bad filter, or clogged filter.
