Popping from Throttle Body upon heavy acceleration?

[REBORN]

Make/Model: 2001 Eddie Bauer Explorer 5.0

Mods: Dual in/single out Dynomax Welded 2 chamber Muffler, High Flow Spectre Cone Air Filter w MAF Adapter on stock CAI. Throttle Body Mod (Cable Ties).

The exhaust and filter have been on for a month, and no problems until last week. This might be coincidence, but it seems to have happened after I used a mixture of fuel injector cleaner & Octane boost with 92 octane gas in the same tank (I usually run 87 octane). I noticed the popping once the tank was almost empty. It sounds like the popping noise is coming from the TB upon heavy revs or acceleration. I've cleaned the MAF (twice), cleaned the IAC (twice) Checked and cleaned the TPS, as well as cleaned the inside of the TB out. I'm having no Idle problems, just feels like some lost power, or even a slight miss. Checked all the wires going into the coil pack, all are getting a decent looking blueish/orange spark. I'm getting no CEL, no codes are being pulled. I've ran a can of sea foam in the newest tank, not much white smoke, probably didn't let it sit that long (5 min).

I haven't had the time to check the fuel pressure, pull the wires, or plugs.
Probably will do this weekend. Does any one have any suggestions? Am I missing anything?

Anything to put me in the right direction, would be great.

REBORN

 

[jlsparky7]

Popping like air or backfire?

Theres no reason to run higher octane fuel in your vehicle. Are you back to 87?

 

[REBORN]

It's definetly a backfire.

I wanted to give the system a good cleaning. She's been running strong since the mods were put on in the past month. I figured a higher octane, plus some injector cleaner would make her run really good.

I have switched back to the lower octane gas now. going on my second batch. I don't usually fill her all the way up, about 20 bucks worth a week.

I did swap back the original filter, thinking the PCM couldn't compensate for all the extra air. Also reset the pcm, and it still does it with the original one in.

 

[Explorsport 2000]

Sounds like a lot of carbon build up on the valve seats or you might have a stuck lifter that will not allow the valve to close properly...2 thinks you can try...add a quart of ATF, this stuff will clean any residue build up that may exist inside the lifter and it should work if it is your problem...the other thing I recommend is a good internal steam clean...what you do is get the engine to operating temp, using a Hudson pumper, like you use for killing weeds, fill it with plain water and find a source where you can keep the engine running while injecting the water before the throttle body...get the idle up to 1500-2000rpm and inject the water till you have a slight load...the engine will want to miss fire once it starts to load up, let off the water and give the throttle a couple of bursts...keep doing this until the engine smooths out...it usually only takes about a quart or two of water to clean all the carbon...this trick I have done on many engines and works very well...I am sure someone will key in and suggest using sea foam engine cleaner, but that means spending money...my trick costs nothing and believes works better...if you don't have a Hudson pumper you can use a spray bottle, just use the stream setting.

Good luck finding your problem.

Dave

 

[Turdle]

Check the harmonic balancer--main crank pulley--

The crank sensor disc is pressed into the assembly with a rubber sleeve holding it firmly in place. However, over time it can slip. The direction it will slip, will cause an advance in ignition timing of a few degrees, and, since it is the reference point for the PCM which has moved, the PCM assumes timing is correct.

Mine was off by at least 5 degrees when I removed it at 102k miles.
I believe the 0 degree timing mark and keyway notch should be in line--but there is also another reference line where you will notice the slip if it has occurred.

You will need to remove the crank pulley to check this.

 

[REBORN]

Thanks guys for the input! I will attempt to look at it, or have someone else check it out over this busy weekend of traveling.

Much appreciated!!

 

[REBORN]

Problem fixed!!

I decided to pull the wire off of plug #8 (Had a heat shield on it), looked inside & noticed it was pretty dark inside. I sprayed some MAF cleaner inside the boot, and let it sit for a few seconds. I repeated this process until everything came out clean. Hooked it back up & no more backfiring. I haven't had a chance to do any of the others yet, but she's running like a champ again!

 

[REBORN]

False alarm!

Started her up this morning driving to work,still doing the same thing. Can the plug foul up the wire that fast? I drove it once last night after the cleaning, and it was fine. Sounds like another problem to me.Well back to the drawing board.

 

[REBORN]

UPDATE.... I decided to clean all of the wires (inside the boots) a couple of days ago. I used the MAF cleaner again as well as some Qtips. They were all pretty dirty inside. Started her back up, and all was good again.

Two days passed, and last night it started to backfire again. This morning I decided to pull plug #8, and cracked the insulator stem right off. So off to the store I went to buy some new ones. The damn truck had Bosch plugs in there. I have never changed plugs before in my life, and it only took about an hour to do. Luckily I had the right tools and extensions to get them things out. The old ones were gapped at about .050 that was with quite a bit of the electrode missing. Gapped the new ones (Autolite Platinums AP104) to .054, and the truck is running great now.

I will be replacing the wires as soon as i can get some more cash (Motorcraft). I haven't had a chance to really test her out, but have noticed better starting, better idle, & way better throttle response. My symptoms usually happen 1 to 2 days after I clean the wires, so we'll see if the plugs were the culprit, or my wires.

I sure hope its fixed!! This is so darn aggravating! I'll keep you all posted.

 

[REBORN]

Back to running like crap again!

Decided to do the spray bottle with water trick tonight on the coil pack and near the plugs, and sure enough its arcing like crazy! I could see arcing on quite a few of the wires, but especially on wire #8. It appears to be arcing all the way down the wire to the boot. It kinda looked like the sparks were traveling up & down the wire. I definitely need to pick up a set of wires now! Just a little strapped for cash right now.

Assuming that this is my problem.

1. Should I go with the Motorcraft wires, or are there others that are better for the same price, or more? (Ford Racing, Taylor Cable, JBA Header Powercables)

2. What would a good size be for a slightly modified 5.0? Should I stick with 8.00mm or go with 9.00mm? I am under the assumption that the 9mm just have a thicker jacket, so they should last a bit longer than the 8mm.

Anyone have any suggestions, before I go buy the cheapest set, and kick myself in the ass 6 months down the line?

Any input would be greatly appreciated!!

REBORN

 

[REBORN]

Just picked up some Duralast 8mm wires from Auto Zone $49.99
(Part Number: 4706). Very nice wires for the price. They came with all the heat shields/wire shields, as well as pre-greased boots, and some extra grease packets.

It took me about 2 hours to put them things on. That passenger side is a *****!

I took her for a test run, and WOW! It feels like i have a new vehicle! Idles perfect! Horsepower & throttle response made my jaw drop! No more arcing, and no more backfiring from the TB. I'm gonna give it a few more days before I'm fully satisfied with the results.

I just want say thank you "Explorer Forum" and all who have given advice! Since having a problem, and becoming a member here. I have become completely obsessed with modding my baby. The wife isn't too happy, she thinks I'm going through a mid life crisis! LMFAO!

Thank you again!!

REBORN