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2001 mustang 6cly won't start

I have a 2001 mustang convertible in good cond. A 6cly that I have had very little trouble with over the past year. I put in a new battery then, just after I bought it from a dealer. The dealer had gone over it with fluids etc. and I had a friend look it over when I bought it. He said it was very clean and a good buy.
So, last week I started having trouble starting it in the morning. It would crank but would not fire. I turned the key off, and then tried again, Same result, cranks but doesn’t start. I turned it off again and being worried about draining the battery, I turned everything off, radio, heat and fan, lights. Then I tried to start it again and, it started. I’m thinking I need new plugs, but I ignored the problem and went to work. A couple days later I was leaving the grocery store, turned the key and same thing again, cranks but doesn’t fire. I knew what to do. Turned off everything and tried it again, it started. Ok, so now some repair, possible plugs, is on my priority list. I need to get this fixed before the bad winter weather comes.
Yesterday, after a long day at work, I was ready to go home and I it happened again. This time it’s terminal. No matter what I did I couldn’t get it to fire. This morning it’s sitting in the office parking lot and I need to deal with this today. Could be plugs, could be the fuel pump. Before I call the dealer and pay 4x what I should for this, what do you think it could be? Has anyone had a similar problem with a similar 3.8 6cly.
The car is sitting on a slight incline, in the parking lot. Gravity pulls fuel from the engine to the gas tank, if a fuel pump is going bad this could be why I can’t get it to start. I’m going to roll it to a level area and hit it with starting fluid to determine if the pump is bad. I’ll also pull a couple plugs.
Anything you can offer would be appreciated, thanks for your interest.

It’s not the fuel pump fuse, I checked the fuse in the box under the hood and it’s fine.
Has anyone replaced a fuel pump in a 3.8 6cly, is it do-able for an amature mech?

You need to find out what the problem is before you start replacing parts. How much are you willing and capable of doing by yourself?

When it doesn’t fire up, first check for spark. This can be difficult on a COP (coil on plug) but if you have a lost spark system or a distributor, you can pull a spark plug wire and check for spark while someone cranks the engine. I prefer to use an old spark plug for this as I can do it by myself this way.

The fuel pump is located inside the gas tank. You up for dropping the gas tank?

If you pull the spark plugs yourself, you can get an idea of any issues by looking at the tips. Google for a guide on this. If you see white or yellow crystals forming on the spark plug tips, you have a head gasket problem. I believe that was an issue on this engine, but not sure that your year applies.

Yea, check for spark. right, I got it. Thinkin a gas tank fuel pump is just beyond my ability, but I have a friend who does this sort of thing, if that’s what I need. For now, I got it running.

I had a friend drive me in to the work lot and first we checked for the sound of the fuel pump, must be a real quiet pump cause we heard nothing at all, over the damn ignition beeper signal. Assuming it was running anyway, I disconnected the air intake and sprayed a generous amount of starter fluid directly into the manifold. Then I tried starting it again. It fired right up…

So, I changed out the old plugs w/original Motocraft plugs @ 4.95 each (when did plugs get so expensive?) and I bought an extra can of starting fluid, which is in my trunk along with a screwdriver for the air intake. Driving it home, all the power and acceleration are there which wouldn’t be if there were a fuel pump problem. I’m thinking clean out the fuel system with an additive, Lucas make one and I trust them but I really don’t like throwing stuff in an engine to “fix” it.
The plugs were spent, dark brown and deposits, they look like the original plugs and there is a lot of rust on the threads. I’d bet they are the original plugs, I’m glad they’re gone. The replacements are all gapped at .054 (spec) and this was an easy job with no special tools needed. Hoping this is the cure but we’ll wait and see before trying anything else.

Anyone have advise on a good fuel system cleaning additive? Any other thoughts on why it wouldn’t start in the first place?

If the plugs are bad enough, it will be hard to start. There is a point in a plugs life where the spark isn’t strong enough for a start but will run once started. The fuel air mix is a lot more variable before the engine starts so it needs a better spark then.

"There is a point in a plugs life where the spark isn’t strong enough for a start but will run once started"
Sounds about right to me… Hope there are no further problems.

I remember when my dad had a 58 Pontiac Bonneville…( wish I had one today ).one morning refused to start, he checked for spark by grounding a plug wire and was nice and blue as he had me turning the key. Had gas as you could smell it coming out of the carb.

I remember the neighbor coming over to help ( I was 12 at the time ), After running the battery down they tried jumping it off the neighbors car with no luck. crank crank crank but sometimes sounded like one or 2 cylinders would fire.

Neighbor suggested it was severely flooded and to try and push start it ( that was when you could push start automatics ). We pushed it into the street and neighbor pushed it with his 60 Buick up to about 30 - 35 mph…Dad turned on the ignition and dropped it into “L”. You could feel the drag from the engine when the tranny engaged for about 100 feet as it must of been turning around 2000-2500 rpm. The Pontiac finally started running rough for a bit but settled down. I guess the higher rpm’s helped clear out the flooded cylinders.

After getting back home they pulled the spark plugs and most were worn down and full of lead deposits from the leaded fuel used in those days. After a spark plug change it never happened again. So worn plugs can cause a no start but will run the engine after you do get it started. You would never think of this during a no start as can all 8 plugs be bad ? Even if 2 or 3 were bad the engine should start somewhat.

Don’t take this the wrong way, but I think some of your impressions are wrong.
Gravity would have nothing to do with this problem unless the fuel level in the tank was very low.

The engine running a few seconds on starting fluid in the intake does not mean the fuel pump is bad with 100% certainty. It only means there is a spark present and fuel is not for whatever reason; be it a bad pump, electronic controls issue with the pump, or even an injector pulse issue.

The pump should run for a second or so when the key is first turned to the RUN position. If the engine is not cranked over by the starter motor immediately the pump will not run after that initial turn of the key to RUN.

A pump can also fail in different ways; dying and staying dead, running at a slower speed and causing an engine lurch, or dying and then coming back to life with everything fine for a day, week, or months before the next spell.

Offhand, I might say the issue is related to the pump controls but there’s not enough info available and I don’t think any additive is going to be the cure.

So, it happened again today. I know it’s not the plugs. A fuel pump is about $109.00 and I’m working on finding someone to put it in. I might replace the fuel filter too. Updates will follow.

As you found out fuel pumps tend to be intermittent. Hopefully this will fix your problem and you will be good to go.

It seems that you still haven’t yet proved if the trouble is related to the ignition system or the fuel delivery system. Since you have some starter fluid already spray some into the intake when the trouble happens again. You don’t need a lot, a one second burst is about all you should need. If the engine fires up then you have most likely proved something in the fuel delivery system is causing the trouble. I would first suspect the fuel pump relay before the pump itself by the way you describe the way the trouble is happening. If you still have no reaction from the engine using the fluid then you need to check the ignition system. As always, first make sure proper power is getting to the ignition system if the problem is in that area.

Ok, so I replaced the fuel pump and fuel filter, myself. This wasn’t what I would call a difficult job but it did present a few challenges. Some of the YouTube video’s I saw said to take out a few screws that did nothing at all, and disconnect vapor lines in places I had a hard time finding. I managed anyway and was able to get the tank out enough to replace the pump. The fill tube and vapor lines were still in the trunk and the tank was hanging/ but supported with a floor jack. Good enough to get the job done and get it all back together. BTW, raising the tank and positioning it to get the strap bolts in was the most difficult part of this job. If you’re planning on doing one, get some help for this part and use a large piece of 3/4 plywood between the tank and jack for support. Other than that, just be careful with the fuel line clips, I broke one and was lucky to have a replacement clip come with the new fuel filter. Also, fuel pumps are not cheep, Ford wants $500, my auto store $209 + filter $12, previously spark plugs cost $30.
The whole thing came apart and went back together easily. No more difficult than replacing a radiator. When I was done, I turned the key to ON and heard the familiar sound of a fuel pump starting. I hope this is the last I hear of this problem…

I turned the key to ON and heard the familiar sound of a fuel pump starting.

But is the car consistently starting?

You guys and your codes, geezz. I’m working on becoming an amature mechanic, I’m just not that knowledgeable yet. I can change oil, plugs, and a belt, maybe replace an alternator, starter, tension pulley. I once took the heads of a 289, cleaned them and put it back together. That was a 1965 mustang and it ran like a beast with a 3 speed manual trans, which I also put in along with the linkage. But, these newer engines have a lot of sensors, relays and switches that I have no experience with. Back in the day('75) if there were a problem, you’d fix or replace the first most obvious possible cause, or easiest, then try it out and if that didn’t do it you’d move on to the next most obvious probable cause. Eventually, you’d find the problem… I know this must sound crazy to some of you, but that’s how I do things.

I did check the fuel pump fuse when it didn’t start the first time. I’m not a moron, I know where the car manual and fuse box are. The fuse is a mini and there is no relay specific to the fuel pump in the fuse box under the hood. So thinking the plugs are so old they’re burnt beyond use,

I replaced the plugs first. The car has 139,000 miles and they looked like original plugs. Good call, the plugs needed replacing, but that didn’t fix the problem…
Next, I replaced the fuel pump and while I was there I replaced the fuel filter too. Good call again because the fuel pump wasn’t starting when the ignition was turned to 1st position, I couldn’t hear it. The fuel filter looked like it had been there, untouched for 12 years. So now I have a “new” fuel filter, and a “new” fuel pump that starts when the ignition is turned to the 1st position, I can hear it. These two items are no longer the cause of the problem, and the car runs now…

As I said, I hope that this solves the problem, but some of you are still skeptical. Tell me, what do you want me to do? Where is the love a good job trouble shooting and fixing my car myself? I guess I’m here alone and I’ll have to pat myself on the back to get any recognition…

The car starts and runs, for how long only time will tell. But for now, I’m totally satisfied. I know it’s put together right because I did it myself and I saved a ton cash by not leaving it at Ford. If it doesn’t start one morning, then I move on to the next most obvious probable cause… whatever that is and as crazy as that sounds.

Thankx for all your comments and advise.

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Congrats on getting it going again. I don’t see any problem with the way you go about your own DIY auto repair. Seems good to me, and it is proven to be effective. Good on you. Keep on doing it, and safely.

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So, it’s been ten (10) days since I replaced the fuel pump and so far I have not had one problem with starting the car. Morning (4am) to go to work, midday (12 noon) for grocery shopping, late afternoon (4pm) when I come home from work, or even once at about 8pm when I needed to go pick up some medicine, for the past 10 days my car has been as reliable as ever.
If it fails to start again, I will be very surprised. I guess I fixed it… so, on to the next thread!!


Good deal. Thanks for the update.

We all like hearing the outcomes. I wish everyone would post their final fixes. It helps diagnosing future posts. Glad to hear you are back up and running.

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Not that I know anything but that sounds like a bad pump or wiring or connections to it. Maybe drew so much current that the battery couldn’t handle it unless everything else was shut down. If you replace the pump, you also need to replace the filter, and you should replace the relay also, as well as freshen up all the connections. Next time take a 2x4 or a 5# sledge hammer and bang the bottom of the tank to try and dislodge the pump. If it runs then for sure a pump issue. I always carried a 5# hammer for my Buick and sometimes it worked and sometimes not.

Edit: Seriously I did not see the second page before I posted so congrats on the pump job and glad it worked.

If you look in the upper right corner of this site’s home page, there is a gray rectangle with a + and the words, “New Topic”. If you click on that link and compose your own thread, you will get a LOT more responses than you will by tagging onto a thread that has been dead for six years.