TOPIC: 2002 Ford Explorer 4.6L V8 - no change after groov

Hello, I purchased a grooved TB straight from Ron. Had initial trouble with correct pcv cap and o2 sensors, both of which are now resolved - I hope. (see forum topic on PCV valve / Port / hose ??).

I'm seeing no increase in power and my mpg is actually down a few mpg. I was initially informed that both of these should increase immediately. After reading some of the sensor issues, I'm perplexed as to how the groove will work at all without manipulating ALL the sensors.

Suggestions please?

After finding out the issue and correcting it, have you reset your computer with the procedure that Ron outlines? If you haven't I would suggest it and you might give the modification some time to work with your computer, 2-3 tanks is what it took my computer to really understand what was happening.

Hope this helps,
Ken

Hey Ken, yes I've reset the computer. Ok, I'll get through a couple tanks of gas and see...
Thanks, Greg

Hi Greg,

One of the items that constantly get scrutinized is vacuum leaks or what can be perceived as a vacuum leak.

Your vehicle has an Idle Air Control valve, simple fix for this is a metal gasket with the intake side hole full size and the output hole side reduced to 1/8". This will allow the IAC to function and reduce the excess air flow that currently exists. Typical material used is either a piece of flashing or an aluminum can.

If this is the vehicle with the aluminum engine thee are a lot of computers involved, if you have an OBDII scanner it would help in understanding wha tyours is doing.

Karl Fortner
Tacoma, Washington

Hi Karl, I have an OBDII to scanner (low end) not sure how much it can tell us. I can make the idle Air Control change pretty quick.
Is there a way to find out the exact engine (code# somewhere). I would agree that this engine does have a lot of computers/sensors that recorrect changes made...(novice view point).
I say this partially because Ron has the same engine but his PCV was not in the same place as mine and I'm not seeing any changes...

Concerns: MAF sensor & Post o2 sensor (after catalytic)

Was debating on placing a screen mesh in front of the MAF and wrapping the Catalytic converter in something in hopes of heating up the post 02 sensor reading (not sure what can get that hot and not melt). I have taken a infra red reading of the temp before and after the cat and the post reading is cooler. Which tells me that the ECU will dump fuel in order to heat up the post o2 sensor.

Any thought/guidance are most appreciated!
Thanks, Greg

Greg try this--get under there and put several wraps of aluminum foil round the downstream cat/cats. Use some baling wire, etc. to secure over cat. Drive a ways and take infrared temps. Infrared thermometer won;'t get readings from reflective aluminum foil, maybe spray a little black BBQ paint over some of outer foil layer. See if this cheap trick changes downstream O2 values.

If it does and ECM responds favorably--they make different types of header wrap I think usually from fiberglass tape like a couple inches wide. Summit Racing online. etc. and speed shops to source it. BUT if you do use header wrap, try to wrap slightly loose so cat can expand hot. I've seen tight header wrap ruin headers from too much heat containment. They have stainless zip-tie things to secure header wrap. Also I think I've seen Thermotech etc. brand header wrap where it's more like a looser sleeve you wrap over the header pipes. Might also consider loosly wrapping exhaust pipe up to/or between upstream/downstream cats to contain heat. Might even get a bit of power this way, exhaust wrap keeps exhaust velocity up, gases slow as they cool, higher velocity helps scavenging of cylinders...

My 2 cents here...?!

Tracy G

Howdy, Reduced the idle air control opening to 1/8" whole - didn't want to run so increased it to 11/64" and she started. Also wrapped the cats in aluminum foil (heavy duty) and went through the ECU conditioning but only did one short power drive after the mellow drive.
Took infrared readings that were a bit perplexing! Reading on the exhaust pipe beside the pre and post o2 sensors were inconsistent depending on which part of the pipe my light was on. I then took a reading on the 02 sensors themselves which "seemed" to give a more stable reading. The pre o2's were cooler than the post o2's. I'm hoping that that is good to go?

I have not done anything as of yet with the MAF sensor??

FYI: This SUV has a sticker on the window that states it is a LEV - Low Emissions Vehicle.

Any suggestions?
Thanks, Greg

Hi again Greg. Ok after ya wrapped the downstream cats, have you seen any change in downstream O2 readings? I'm curious if there is correlation there from the wrap. You say the downstream O2's are hotter now that makes sense. How much hotter?

Infrared readings--well I've done those too and never got predictable reliable results on several vehicles. Even cars that got strong power/mpg results I never got the temp drops others have...don't know why. Odd idea-- I wonder if readings vary with different infrared themometers?

Back to basics. You are now certain of No vac. leaks, yes? TB mounting gasket is OK?

I forgot if ya mentioned--the O2 sensors that were put in, were they factory ones or cheaper aftermarket ones? It has been found that for many/most vehicles the cheaper ones don't work out as well as OEM ones More$$ but that's the story as I understand.

I think I might back off from sensor manipulation for now. I would try to get as satisfied as possible that all basic stuff is good 100%. Then I would do the computer re-learn as exactly as Ron and training manual says. Again its- pull + cable from batt. Jumper loose + cable to ground, turn key to run w/ lights switched on. Wait ahwhile, 30 min or more. Turn key/ lights off be sure everything is off. re-connect batt+ cable to batt. Start engine let warm a few min. Listen for idle RPM to drop (the IAC reducing flow) shut off, re-start, wait for idle RPM to drop wait 2-3 min. shut off. Do this on/idle drop/wait couple min./shut off thing like 9 times. Then start, and drive it at least 10 feet( I go partway down block). pull over, shut off. Wait a moment start go at low speed (I go around corner) pull over stop shut down. Each time now I re-start I wait for idle RPM to drop then go a ways (block or so), pull over stop turn off. 5 or 6 of these then it's up to 25, then 35, then 45, 55 0r 60. Pulling over and shut down, going up stairsteps of speed till the hiway run.I try to do at Least 5 miles at 60-65. I get an offramp get off find place to park. Shut down, then re-start get back on hiway for the full throttle boogie! After fulll throttle run I bring back to my driveway driving normal/sane Takes some planning to figure route.

Every time I've gone thru this extended long re-learn it's worked for me even on a big Ford Triton v-10 F-350 that got a 33% MPG increase on a Mountain trip w A/C on! But I made sure of no vac. leaks running OK first.

Enough about me--I can't stress the basics enough Greg. So many have got results this way, some vehicles are stubborn is all. Do you have the Training manual or are you simply a Mail-in Mod customer of Ron's. I've assumed all along you got the basic Gadgetman Personal Liscence. I'll still help ya either way. I just don't know how much info you have at hand.

Keep at it we'll get this one down to size!

Tracy G

Hi Tracy, my obd11 only shows codes:-(. The new o2's are supposed to be oem quality.
Vac leaks should be non existent. Ever since the idle air port was downsized to 11/64 hole the idle rpm is at 800ish, used to be 600ish...Doing your ecu conditioning now.
thx, greg

Anyone please, Still no change. After reducing the idle air control to 11/64" hole she starts and idles very differently, doesn't restart very well and sometimes doesn't want to start after shutting off for a few minutes.
At first start it immediately runs at lower idle rpm (there is no rev up and then idle down).
Before she would idle at 600+ rpm, now it is 800+ rpm unless I turn on A/C then it goes down to 600+ rpm.
At first start she runs rich for awhile but goes away.
She seems to run normal after warming up.

I just refilled up and my mpg's were still low. 15 mpg combo hwy/city!

Any suggestions?

Thanks, Greg

Greg change the hole in IAC restrictor plate, go bigger. Or smaller? It's easy.

Tracy G

Hey Greg!
(Got your message, but couldn't find your number.)
It would be good at this point, as your relevant messages are in many posts, to give a recap, starting with the conditions prior to Grooving the TB.

You can skip the problems and talk of what you found.

Now, with my Expedition (a match for yours) it actually started at 9, went to 24, then settled down to about 14 (YUCK!) recently. I am at a complete loss as to WHY, but I am beginning to believe there is a minimum acceptable level of prolonged consumption level programmed into the ECU.

I would suggest clearing the ECU again-and doubling the recommended time of 15 minutes to be sure the job is done.

Remember, give us the highlights once more and we'll do our best to get you up to what you want!