Odd issue with my 99 explorer

[outlawz360]

Thank you all for your advice, It’s much appreciated. the pump did drop lower then 57 psi once, I’m pretty sure thats the main issue then Probly the wires ain’t helping. It’s so stupid how they connect to the ignition coil which in itself looks rough. There might be a slight vacuum leak somewhere too, thought I heard one but can’t find anything

 

[donalds]

Fix one thing at a time or you won't know what it was and it will confuse you just like the rest of us

 

[Cobraguy]

Sounds like a fuel delivery problem to me. Pressure is not always a good indication. You need volume as well as pressure. You can easily have enough pressure, but no where near enough volume. This could be as simple as a fuel filter.

 

[J$hort]

Start with simple solution, change filter if you have not done already. I swapped my pump out years ago and the symptoms sound familiar. I had to drop the tank in the 95 so it was no small job. Exhaust all the simple items listed here before you lay out $ and time on swapping pump.

 

[Cobraguy]

Good advice. Of course, the best option would be to perform a volume test...

 

[mercabago55]

So I did look on the forums and I really couldn’t find my exact issue? I have a 99 explorer xlt 4.0l sohc 128,800 original miles, everything is still original from factory on it except the alternator, plugs and fuel filter, Anyway it has this odd issue that has gotten worse since I got it a week ago, it does feel a bit underpowered so maybe it has something to do with it but who knows. This intermittent issue happens when I Press on the gas more then lightly, it will sputter/surge and lose power and will now stall sometimes. It won’t happen all the time but it has gotten more frequent and just all around worse. If anyone has any ideas please let me know. I thought maybe coil pack or fuel pump

Had Similar problem with my 2000 Exp,found that it was water in the gas went away after a while.

 

[Deleted member 352605]

@mercabago55 while yes, that could be the problem, i wouldn't count on it... if there is enough water to have an effect, it mustve gotten there somehow. so, if there is water, i wpould recommend seeing where it came from...

 

[jon clarke]

So I did look on the forums an d I really couldn’t find my exact issue? I have a 99 explorer xlt 4.0l sohc 128,800 original miles, everything is still original from factory on it except the alternator, plugs and fuel filter, Anyway it has this odd issue that has gotten worse since I got it a week ago, it does feel a bit underpowered so maybe it has something to do with it but who knows. This intermittent issue happens when I Press on the gas more then lightly, it will sputter/surge and lose power and will now stall sometimes. It won’t happen all the time but it has gotten more frequent and just all around worse. If anyone has any ideas please let me know. I thought maybe coil pack or fuel pump

I would look toward the catalytic converter. When blocked the more you try to push through it the worse it gets. Babying the throttle works better than mashing it.

 

[Cobraguy]

I would look toward the catalytic converter. When blocked the more you try to push through it the worse it gets. Babying the throttle works better than mashing it.

That's true too...

 

[jmops]

So I did look on the forums and I really couldn’t find my exact issue? I have a 99 explorer xlt 4.0l sohc 128,800 original miles, everything is still original from factory on it except the alternator, plugs and fuel filter, Anyway it has this odd issue that has gotten worse since I got it a week ago, it does feel a bit underpowered so maybe it has something to do with it but who knows. This intermittent issue happens when I Press on the gas more then lightly, it will sputter/surge and lose power and will now stall sometimes. It won’t happen all the time but it has gotten more frequent and just all around worse. If anyone has any ideas please let me know. I thought maybe coil pack or fuel pump

If you think it's wires open the hood after dark when the engine is running. My old LTD looked like the 4th of july when I did that. New wires and it was OK.

 

[sailin4]

So I did look on the forums and I really couldn’t find my exact issue? I have a 99 explorer xlt 4.0l sohc 128,800 original miles, everything is still original from factory on it except the alternator, plugs and fuel filter, Anyway it has this odd issue that has gotten worse since I got it a week ago, it does feel a bit underpowered so maybe it has something to do with it but who knows. This intermittent issue happens when I Press on the gas more then lightly, it will sputter/surge and lose power and will now stall sometimes. It won’t happen all the time but it has gotten more frequent and just all around worse. If anyone has any ideas please let me know. I thought maybe coil pack or fuel pump

check the vacuum lines for cracking

 

[Blue Oval Charlie]

@outlawz360

No mention of replacement spark plug wires.

The FORD wasted spark ignition system on both models of 4.0 V-6 (ohv & sohc) dictates that one bank of spark plug wires (3 wires in total) effectively have 256,000 miles on them.

My .02 = Motorcraft or Denso brand spark plug wires for the win

Hope that helps and welcome to the forum!

Your Explorer is a 3rd Gen. The Explorer in question is a 2nd Gen. It doesn't have the waste spark. It actually has 1 wire per cylinder.

It sounds, to me, as if there is a small vacuum leak or a sudden drop in fuel pressure when he depresses the accelerator more than 15-20%. The fuel pressure regulator may be the cause of both, as it is vacuum actuated.

 

[donalds]

Yes it does

 

[Mbrooks420]

Your Explorer is a 3rd Gen. The Explorer in question is a 2nd Gen. It doesn't have the waste spark. It actually has 1 wire per cylinder.

It sounds, to me, as if there is a small vacuum leak or a sudden drop in fuel pressure when he depresses the accelerator more than 15-20%. The fuel pressure regulator may be the cause of both, as it is vacuum actuated.

As Donalds has already confirmed all second gens are wasted spark. Wasted spark has one wire per cylinder.

 

[donalds]

Might be thinking of a ranger with the ill 4 banger with 8 spark plugs

 

[Motolz]

I had a similar issue and it was the mass air flow sensor

 

[MrQ]

Your Explorer is a 3rd Gen. The Explorer in question is a 2nd Gen. It doesn't have the waste spark. It actually has 1 wire per cylinder.

It sounds, to me, as if there is a small vacuum leak or a sudden drop in fuel pressure when he depresses the accelerator more than 15-20%. The fuel pressure regulator may be the cause of both, as it is vacuum actuated.

All second gens, regardless of motor, are wasted spark. Same with any 3rd/4th gens with the 4.0 SOHC engine. I think the 4.6 was the only one that got coil-on-plug.

No vacuum FPR on the return-less systems (99-01).

One wire per plug is not the best indicator of a waste spark system. Waste spark basically fires two cylinders with one computer pulse (one on the compression stroke and the other on exhaust) and it has to do with how Ford decided to control the coil pack (it's easier, cheaper, and requires less programming to fire two cylinders with one wire). Distributor style EFI systems with one plug per wire are also not waste spark.

 

[marc ford]

So I did look on the forums and I really couldn’t find my exact issue? I have a 99 explorer xlt 4.0l sohc 128,800 original miles, everything is still original from factory on it except the alternator, plugs and fuel filter, Anyway it has this odd issue that has gotten worse since I got it a week ago, it does feel a bit underpowered so maybe it has something to do with it but who knows. This intermittent issue happens when I Press on the gas more then lightly, it will sputter/surge and lose power and will now stall sometimes. It won’t happen all the time but it has gotten more frequent and just all around worse. If anyone has any ideas please let me know. I thought maybe coil pack or fuel pump

change fuel filter first. If that is not the problem, fuel pump would be next on list

 

[Chris Lippold]

So I did look on the forums and I really couldn’t find my exact issue? I have a 99 explorer xlt 4.0l sohc 128,800 original miles, everything is still original from factory on it except the alternator, plugs and fuel filter, Anyway it has this odd issue that has gotten worse since I got it a week ago, it does feel a bit underpowered so maybe it has something to do with it but who knows. This intermittent issue happens when I Press on the gas more then lightly, it will sputter/surge and lose power and will now stall sometimes. It won’t happen all the time but it has gotten more frequent and just all around worse. If anyone has any ideas please let me know. I thought maybe coil pack or fuel pump

I'm not sure if this Will help but my 94 olds 88 that had a sporadic idle and after i cleaned my throttle body and replaced my tps it started showing your exact problems. I checked my maf and it was broken. I changed it out and now my car drives like brand new. I would check your maf sensor and clean it with maf cleaner if its good. And i'd also clean the throttle body with cleaner..
Good luck, hope this helps

 

[mercabago55]

@mercabago55 while yes, that could be the problem, i wouldn't count on it... if there is enough water to have an effect, it mustve gotten there somehow. so, if there is water, i wpould recommend seeing where it came from...

I got the water at a off brand gas station,do not go there anymore,problem solved