1996 Explorer 5.0, Miss at idle

[Spartan]

Hey all, I ahve a 1996 Explorer 5.0 with 2wd. Ive had this problem for a year or so, and its not gettign any better... perhaps a slight bit worse.


It misfires at idle. enough were you can feel it in the truck, and maby slightly hear it. ABSLOLUTELY no trouble codes, not CEL, a bit down on gas milage, but nothign terrible. I've replaced plugs and wires in the last 6 months, cleaned the IAC, all of that. nothng has touched the miss.

I have a passengers side exhause manifold tick (may be the crossover pipe underneath, its louder when cold, almost goes away after warm) but I don't know..


help!

 

[Spartan]

any ideas of what I can check?

 

[RyansX]

I have the same problem. Subscribing to see what the issue is

 

[UrbanRedneckKid]

Mine has the same 2 issues.

Miss is the cam synchronizer, my CEL is on now, but wasn't for about a week.

Exhaust leak is the EGR tube, supposedly supposed to set a CEL, but hasn't yet.

Yours may be something else, but that's what mine is...

 

[Spartan]

My truck does not have an EGR, or an EGR tube for that matter.

The miss has been around for a bit over a year not, with no other issues whatsoever. Like I said, I know that the CEL works, but there are not any trouble codes stored in the computer, and Ive never had a CEL pop up. (I made sure the bulb was working btw)

I'm going to try and diagnose some stuff thsi weekend. I;m going to check timing, spark strength on all wires, ect.... I'll see what I can come up with. I know my fuel pump is whiney, and the filter hasnt been changed since Ive owned it, so mabey i'll start with that.

 

[Spartan]

So, just an update. Truck still has the miss, still has the exhaust tick. Still haven't figured it out.

 

[james t]

Tick will be the passenger side manifold gasket. Or header (whatever you want to call it), since the stock manifolds are actual tubes and not cast. Check the bolts... id bet money they are barely tight.

Easy solution, just get a set of copper or aluminum header gaskets and replace. It's easy to get to with the truck jacked up and the inner fender removed. The passenger side is the easiest to work on so if you want just replace that side.

 

[koda2000]

as you don't say... have you changed the spark plugs and wires? use Motorcraft or Autolite plugs (at least Platinum grade), and good quality plug wires. that would be the place to start. while the plugs are out, do a compression test to eleminate valve and ring problems. beyond that, you could throw a container of Chevron Techron fuel system/fuel injector cleaner in a 1/2 tank of gas in case it's a dirty injector. if all else fails, you've probably got a bad injector.

 

[pbnj22]

I have the tick as well which i assume is my egr tube but i am getting torque monster headers so it will fix that issue... your truck because it is an earlier model should have an "internal" egr if that makes a difference.. and i had your similar miss fire as well.. changed plugs and wires with some off the shelf ones at an auto parts store and it was still there so i dug deeper and did the fuel treatment, injector cleaner, fuel filter, checked fuel pressure, checked compression... brought it into the shop at my school, installed "motorcraft" plugs and wires for the hell of it and bam it went away and ran fine... moral of the story make sure you run these specific plugs and plug wires as mentioned above

 

[koda2000]

I have the tick as well which i assume is my egr tube but i am getting torque monster headers so it will fix that issue... your truck because it is an earlier model should have an "internal" egr if that makes a difference.. and i had your similar miss fire as well.. changed plugs and wires with some off the shelf ones at an auto parts store and it was still there so i dug deeper and did the fuel treatment, injector cleaner, fuel filter, checked fuel pressure, checked compression... brought it into the shop at my school, installed "motorcraft" plugs and wires for the hell of it and bam it went away and ran fine... moral of the story make sure you run these specific plugs and plug wires as mentioned above

yeah, Motorcraft or Autolite plugs and wires do make a difference on these engines. (Motorcraft is made by Autolite) and platinum plugs are the minimum requirement for these ignition systems (I use Autolite double platinums gapped to .054) and have never had a problem with them. they should be good for upwards of 90k. the Motorcraft plugs are nickel coated, which I prefer, but they're a little harder to find in the local auto parts stores. as rust isn't a big concern in Georgia, the Autolites are fine for me.

 

[Spartan]

Yep, i just tuned the truck up with no effect. Motorcraft wires and plugs. I also recently did a fuel filter, air filter, cleaned the IAC, AFAIK, the bolts on teh passenger side header are tight. I put a ratchet on them when I was doing upper control arms and balljoints this last weekend.

 

[pbnj22]

did you gap the plugs correctly? .054? next i would suggest renting a fuel pressure gauge for free from an auto parts store and making sure you have the right fuel pressure?

 

[Spartan]

Just an Update here, because I hate searching threads without resolutions. I have swapped the fuel filter, but I havent had a chance to borrow a fuel pressure gauge. No Change. Sometimes it idles jsut fine, other times it has a random miss with no CEL.

2 Things I KNOW are wrong at the moment:

Passengers side exhaust manifold has a crack. This was confirmed, its behinnd the heat sheild. Fuel trims appear to be okay on that bank though..

The fuel pump makes a TON of noise. I'm not sure if its the OEM pump or not, but it makes a high pitched whine constantly. The only time its quiet is when it real low on fuel.


I'll be swapping out the fuel pump this weekend. For the first time the other day, I punched the gas and let it rev out, and got detonation. There's no reason why with the truck running at aboout 192* coolant temp that it should detojnate, unless I lost some fuel pressure all of a sudden. This may be the cause of the miss, I'll update after the swap.

 

[Spartan]

Back again, raising this from the dead. The Damn miss is still present. I'm swapping plugs AGAIN, I recently ohmed out the wires and they are fine, nothing is arcing. I also swapped in two brand new coil packs, Motorcraft. No effect on the miss. It seems to be more pronounced when the truck is in hot weather and warmed up. Any new ideas in the last 5 years? Fuel pressure is fine, I did end up swapping the pump out and that was not the issue. Plugs are definitely in order.... LOL I didn't realize that I had last changed them in 2013... hahah The best part is that the truck hasn't lost any fuel economy, and the miss hasn't gotten any worse.

 

[974X4BLACKSPORT]

A cranking compression test is needed. This will tell you the condition of the piston rings and valve/valve seats. A burnt valve or a bad valve seat (usually exhaust) can leak enough compression to cause a miss at idle, but under load the miss will only be very slight or not noticeable at all. I cant say what your cranking compression should be, most stock street engines produce around 120 psi cranking, and all cylinders should be withing 10 percent of each other.
You have to know the condition of the mechanical parts of the engine, or else you will just be throwing parts at it.

 

[410Fortune]

Its very likely going to be a bad injector, plugged and not firing

Take a look at your spark plugs when you pull them, which one looks wet or black or different from the others?
I BET you have a bad/plugged injector.
Over the years I have seen this many many times with these Fords no CEL, good ignition and still a miss....
Almost always its an injector.
Injectors can be removed, cleaned and tested out of the vehicle = I bet you find your issue

 

[nameskreen]

How hard is it to pull the injectors on a 5.0?