Fix my Ex and we will pay $$

[kristykai]

Hello forum members,

Couple of Aussies here with a big problem and willing to pay any kind soul who can help us figure it out.

Specs: 1999 Ford Explorer XL (UR) 4.0L V6 OHV VinX (engine stock) 3" body lift 285/75/16 tyres that's it no other mods.

Symptoms: No power, doing 80L per 400km (used to do 800km) other than that runs smooth as silk.

Parts list already thrown at problem (all Motocraft): IAC, TPS, MAF, Plugs, Leads, Coil, DPFE (including two new hoses), Cam Chain, Tensioners, Sprokets, Both Heads rebuilt (xrayed and pressure tested using old valves), All gaskets from top to bottom of engine replaced, Plenum tested for straightness, Thermostat, Belts, Engine Temp Sensor, Dash Temp Sensor, (Wires from Loom to Temp Sensors, MAF, Oil Pressure, O2 Sensors & Injectors replaced with new connectors), Injectors, Air Cleaner (replaced with POD), EVAP Solenoid, Fuel Pressure Dampner, Fuel Filter, Fuel Pump (including FPR), Cam Position Sensor and Sender, Crank Angle Sensor, O2 Sensors (one each side after exhaust manifold as there are no pre and post Cat sensors on this vehicle), Alternator/Generator, Battery, Clutch, Pressure Plate, Bearings, Flywheel, Slave Cyclinder, New Bakes all round including shoes on the handy. Only thing not replaced to this point is the ECU/PCM.

Vehicle is not OBII for some reason even though it should be for that year and Vin code. It comes up on 3 different scanners tried as OBDI. Also it doesn't appear in any parts manuals anywhere.... There are UQ's US's and UT's but no UR... so looks like we got some kind of weird non existant throw back truck.

Current Status: Currently the vehicle suffers from a total lack of power and horrible gas mileage. It no longer smells of gas, the exhaust has a nice colour, it doesn't stumble (tested with toilet paper at exhaust) and other than the fuel usage and lack of power runs like a dream. Idles perfectly, no MIL light and no codes showing

What we've tried to fix it... you name it we have tried it. The entire engine has been pulled and everything except the bottom end has been rebuilt. The cyclinders show a pressure of around 170psi across all cylinders (wet) and around 155psi (dry). Head gasket had previously blown on Cylinder 1. Strange thing we noticed is that the plug in this cyclinder is a nice brown colour (rust coloured) although the cyclinder is firing and injector is spraying, all other cylinders are a lovely white colour (according to haynes manual this is perfect).

Occassionally when we go over a large bump the vehicle comes good and all the power and mileage return until we go over another bump and then it's back to normal. Our feeling is that the vehicle has an electrical problem somewhere but we have no idea where to start. All the earths have been checked, the entire wiring loom has been checked for continuity with a Multimetre.

PLEASE HELP!!!... We can't afford to drive our baby due to the high price of gas in Australia these days and we miss playing with her. If anyone can help us find the problem we are more than happy to pay you. We can follow direction well and one of us used to be a qualified Mechanic. We've been trying to find this gremlin for two years now without success.

We can be contacted via this forum, email at kristy_kai@hotmail.com or phone on +61448808535. Thank you all in advance.

 

[Karpiel73]

Holy moly that's a lot of work done. These may sound like dumb questions but:
Are the brakes dragging? Maybe when you hit a bump they unstick and vice versa
Checking the emergency brake too. I removed mine because it wouldn't release fully.
Is it 4x4?
Have you had the computer calibrated since the huge overhaul?

More intelligent people on here will chime in but these are what comes to mind. Good luck!

 

[Juggernaut31]

Also one thing not mention is clogged cats. an easy test is to unbolt the cats, you can even wire the exhaust up in place and try a quick run, if it opens up = clogged cats, if it doesn't make any difference, not the cats. but it does trouble me, no o2 sensors. just something (Free) to try.

 

[Bobmbx]

Does the engine respond smartly to throttle inputs? If so, I'd look into the drive train.

It sounds like your clutch is slipping (if its a manual), or your tranny needs a rebuild (if an auto).

 

[2000StreetRod]

Update pcm?

It is extremely difficult to determine problem sources without the use of the onboard diagnostics. If you plan to keep the vehicle and have access to a Ford dealer I suggest updating the PCM firmware. Then you will be able to use a scanner to guide your repairs instead of just replacing parts.

I am surprised that you have the OHV instead of the SOHC V6. Most of the Explorers exported to Australia were VIN E. Do you have PATS which was implemented in the 1999 and later models in the United States? Maybe the exported models didn't have it which might explain the different PCM calibration. I checked earlier and later model years and did not find a UR but it could just be obsolete and not listed. Below are the latest PCM calibrations for model year 1999 according to Ford Motorcraft. However, it may not include exported models.

Most Recent Software Part Number for MY99 EXPLORER, 4.0L
If the vehicle you are servicing has a Software Part Number other than the ones shown below, there is a later calibration available.
The hardware type is provided for reference only. It does not indicate that the Hardware Type listed is appropriate for the vehicle you are servicing.

Part Number Module Catchword Hardware Type
XL2F-AGB PCM JNJ1 ML2-8B2
XL2F-AHA PCM EPW0 ML2-8B2A
XL2F-HD PCM XQX3 ML2-841
XL2F-JC PCM YMA2 ML2-842
XL2F-JC PCM YMA2 ML2-842A
XL2F-KC PCM ZRA2 ML2-842
XL2F-KC PCM ZRA2 ML2-842A
XL2F-RE PCM CUC4 ML2-842
XL2F-RE PCM CUC4 ML2-842A
XL2F-UE PCM EWE4 ML2-8B1
XL2F-UE PCM EWE4 ML2-8B1A

 

[kristykai]

[MENTION=104625]Karpiel73[/MENTION]... No such thing as bad advice that's why were asking...lol. Were out of idea's.... Yep she's a 4X4 with the automatic selecter switch on the dash.

Brakes are brand new all round including the shoes on the handbreak drums and we have actually jacked her up and given them the spin test without any binding or sticking although interesting thing is that the handbreak no matter how well adjusted seems to let the truck roll and obviously tightening the spindles to much results in binding and that lovely smell that you get when your burning bonding material.

Haven't had the PCM recalabrated unfortunatly since Australia is basically a no knowledge zone for Explorers and even the Ford dealers at least locally anyway are clueless and staffed by children with white lab coats and vague expressions...lol. We've actually taken it to three of them with the same result..."We don't know what's wrong or even how to diagnose it because there are no codes"....(basically there don't seem to be any decent old school mechanics around here)

Will definitely try disconnecting the handbrake and slacking the shoes right off though just in case that is the problem and it's masking things... There was a CIL light when she initially had all the problems but since then there is nothing... She even has a nice healthy coloured exhaust and no gas smell like she had when we first started trying to fix the problem... We have also thought of rebuilding the calipers on the off chance that one of them is sticking although it would usually be pretty evident from either pulling or going through pads quickly if that were the issue... but for the sake of a few more $$$ to Rock Auto for the Seals it's worth doing... =) Thanks heaps for the ideas

 

[kristykai]

[MENTION=225001]Juggernaut31[/MENTION] Definitely not clogged cats they got cut out and welded back together two years ago when the problem first surfaced. Back then she was really stinky on the gas smell out the tail pipe and since that would block them up pretty quickly we decided to fix that issue before it caused another symptom...lol.

Even after that has happened we've actually unbolted the exhaust at the Cat's and let her run to see if the problem was fixed but....nope still same lack of power... She does have O2 sensors x 2 one on each side of the crossover pipes from the headers just not pre or post cat sensors as this model didn't come with them.

 

[kristykai]

[MENTION=230176]Bobmbx[/MENTION] Yes it does respond in an all be it sluggish manner thanks to the lack of power. Although interestingly again it stopped hanging when returning to idle after we install a new 130A TYC brand Alternator/Generator (thinking it might have AC Feedback which was stuffing the ECU/PCM's calculations) but unfortuntely due to TYC's crappy "Brand New" Alternator developing an overcharge problem at 19.84v 10 mins after install and blowing the GEM module we have now had to put the old Alternator back on which although it's charging normally could still be a source of AC Feedback and is reading around 5v on that score...

Clutch and drivetrain wise... we've thought of that one to... The whole problem with the X Started thanks to a change of clutch (and resultant head gasket/thermostate problem) and since we had the engine out again about a month ago we decided to put a brand new clutch, pressure plate, bearings, Flywheel and Slave Cylinder in at the same time... The box itself is Manual and runs perfectly with no noise, no wering etc...

 

[kristykai]

[MENTION=111113]2000StreetRod[/MENTION].... Tell us about it... We still can't work out why it's OBDI and not OBDII... We definitely plan to keep her but as we posted previously the Ford Dealers in Australia either look at you blankly because they don't know what actual diagnosis is anymore if the computer doesn't tell them to replace things or they make that age old joke about "EXPLODER"... which get's even more blank stares when you explain to them that it's not the SOHC engine it's the OHV which is usually rock solid.

We agree that most of the X's we see in Oz are the SOHC V6 and we've had one ourselves but with all the issues they have we specifically went looking for an OHV which ran with more power than you could poke a stick at when we first got it prior to all these problems...

Not sure what PATS is but would love a bit of an explaination on that one if you feel inclinded to share your knowledge with us =). We would have thought even if it were obsolete there would still be a record somewhere...lol but nope... doesn't appear in any books, service manuals etc etc...lol

Any idea where we would find the Software Part Number? Sounds like a good starting point at the very least.

Thank you again all of you for chiming in... We are totally desperate here and at our wits end...=(. All your help and ideas are very very much appreciated and if we find the problem we will certainly be sending some bucks to whoever has the winning idea =).

 

[JusTheUsual]

Just throwing some tips I had problems with...

I have a 99 explorer sport xcode. I replaced the passenger side front caliper 3times in one year. brand new caliper, barely lasted a month, replaced it again, lasted about 3 months, replaced it again, has been working for over a year now. It's that unlucky factor of buying new parts that don't work right, twice in a row. I would get bad gas mileage and loss of power at higher speeds like 55mph. It only happened at higher speeds like 40-55mph, sometimes I could smell the brakes or would smoke, only couple times it smoked or smelled is how I knew the caliper kept failing, twice in a row at higher speeds.

If you've done or should say replaced motor or rebuilt it, my brother went through a problem where it didn't like to rev right at higher rpms. The cause was somehow that motor was junk even though it was rebuilt. Maybe because it was 5 cylinder hummer engine... Only a brand new engine worked, rebuilding those engines twice doesn't work, if you don't have a working engine, buy a new one, they are junk engines

 

[Karpiel73]

[MENTION=104625]Karpiel73[/MENTION]... No such thing as bad advice that's why were asking...lol.

Good luck gettin it all fixed up!

 

[ranger7ltr]

Can you remove the Y-pipe at the manifolds...

And then drive it briefly???One problem I have seen is a collapsed inner exhaust pipe restricting exhaust flow...Engine would start and run fine at lower rpm...Just used lots of fuel and turn a while longer to get to speed...

Just another thought...

[MENTION=225001]Juggernaut31[/MENTION] Definitely not clogged cats they got cut out and welded back together two years ago when the problem first surfaced. Back then she was really stinky on the gas smell out the tail pipe and since that would block them up pretty quickly we decided to fix that issue before it caused another symptom...lol.

Even after that has happened we've actually unbolted the exhaust at the Cat's and let her run to see if the problem was fixed but....nope still same lack of power... She does have O2 sensors x 2 one on each side of the crossover pipes from the headers just not pre or post cat sensors as this model didn't come with them.

 

[kristykai]

[MENTION=233565]JusTheUsual[/MENTION]... Mate any tips are good tips... I (Kai) was a mechanic for 10 years before my back gave out and I can honestly say only a stupid mechanic thinks he knows it all...lol. Were putting in an order Friday night (once the weekly pay packet comes through) for a new Alternator/Generator (trying a different brand this time) and will be ordering a new set of caliper seals for each corner at the same time (can't afford new calipers as much as we'd love a nice new set with the cross drilled and slotted discs to go with em...lol) Have rebuilt around 50 sets in my time so it shouldn't be a big job (unless the pistons or bores are pitted or scored). The symptoms you suggested kinda fit with what were seeing except for the fact that she has no power off the mark either and feels literally as though the handy is on (another little thought that Karpiel73 suggested we check)...

As far as the reving goes there is no noticable problem there aside from the hanging return to idle and in between changes with a slight high rev then settle... The engine at least in neutral rev's well between all ranges with no noticible hesitation. I've done everything on the engine side of things shy of sticking a prob up the tail pipe and having a full computer analysis done with a diagnostic machine which unforunately much like the new engine idea is a bit out of my price range...lol.

 

[kristykai]

[MENTION=104625]Karpiel73[/MENTION].... Thanks mate. Your idea's are very much appreciated. Just hope one day we can return the favour with another member or two... Will keep this thread alive with posts on how we go as we go though so feel free to chime back in if anything catches in your brain that we haven't thought of or tried =)

 

[kristykai]

[MENTION=7538]ranger7ltr[/MENTION].... mate great idea... Funny you should mention that one.. She does have a colapsed muffler at the back as you can hear it rattle around. We have actually tried disconnecting the pipe from the Cross over pipe section before the cat and driving it around as we did have the whole restriction thought ourselves but it made no difference and that was even after leaving the battery unhooked for a few hours to try and clear the memory... Any idea if there is something else we should be doing computer wise before trying the pipe disconnect again to see if it fixes things? As in is there are currently no codes but do we need to somehow get the computer to forget anything before trying it and if so how long would we have to drive it before we see whether the power comes back?

Also just thought we should mention that every once in a while when we go over a big bump all the power comes back so your idea does kinda fit as well as our current idea that something electrical is making occassional contact and throwing all the planets back into alignment...lol.

Once again keep those idea's coming guys and girls.... we very much appreciate your knowledge and hopefully we will be able to get the full HP and gas mileage out of her very soon =)

We will be trying all your ideas this coming weekend as well as having a look at the computer to make sure there are no burned/loose connections on the circuit board (just a thought)

 

[kristykai]

@ ranger7ltr... sorry forgot to mention... yes we have tried disconnecting the manifolds and driving it about 2 months ago when we did the timing chain, tensioner and clutch etc... nice throaty roar to her when she took off but same no power scenario...=(

 

[ranger7ltr]

On to the next one...

I see you have changed the fuel filter, fuel pump and FPR... What is the fuel pressure at the test point on top of the passenger side of the engine? When I first started driving my 99 Explorer the fuel filter would clog up from rust in the tank...Changing the fuel filter only got me 2-3 months before it happened again... I eventually changed the tank and fixed the rust problem for good...

Also follow the fuel inlet and see if there is only one fuel line to the manifold or two lines to the manifold...If there is 1 line the operating fuel pressure should be 65-72 psi but the engine would run as low as 25-30...Not well and DEFINITELY down on power but it would run...If there are 2 lines then the fuel pressure would need to be 30-45 psi dependent on throttle position[change in vacuum to the regulator]...

And was the regulator in the tank or on the intake???I like a challenge but you have changed more parts on your truck than I have and I put over 70K on it in 3 years...

Oh and low fuel pressure will not trigger a check engine light until there are enough misfires to trigger a code...Otherwise you will not see a code set...

 

[Turdle]

If there is a short circuit to ground in the fuel injector harness, this would cause the injectors to switch "on" steady.

The OHV fuel injector harness routes under the alternator on obd1 trucks. the 0 v side is common, and can develop a bare spot where they join up, and even wear thru the conduit.

Is the PCM in the firewall?

 

[kristykai]

[MENTION=7538]ranger7ltr[/MENTION]... believe it or not you are one of the first people we started reading all the posts of on here due to your exceptionally diverse knowledge on the subject of X's =).

In terms of the configuration of our X's fuel delivery system it goes like this...lol. She has the returnless system with one line. The Fuel Pressure dampener on the side of the Fuel Rail is brand new as is the Fuel Filter and Fuel Pump/FPR on the pump in tank.

The tank is absolutely spotless inside, the lines have all been checked for leaks and blockages right the way from the tank to the rail and using the old fashioned (dodgy way of smoke testing we used cigar smoke to test for leaks (no one in Australia seems to have a proper smoke tester).

Fuel pressure is spot on both at idle 70psi and off (checking for pressure drop). Don't know what the Fuel pressure is whilst driving as the line from my tester won't stretch far enough to sit up under the back of the hood (yes one of us used to live in the U.S. so we know the correct terms...lol). If you have any cheeky idea's how to test the pressure whilst driving we would welcome them.

As far as misfires goes... we aren't sure that the OBI would pick that up even if there was a misfire although if you know otherwise we would welcome the knowledge on that... We did notice when we pulled the engine down recently that No1 Cyclinder was dry as a bone and rust coloured at the exaust port (plug was a perfect colour) which made us wonder if under load she wasn't getting any juice but honestly that idea doesn't match up with how smooth it feels when accelerating (once again feel free to throw out your thoughts)

Hasn't had a code come up ever since we replaced all the parts which was over a year ago. It wasn't very smart of us to replace things all at the same time as it makes it very difficult to find a fault if you don't know what individual part fixed the problem but since the problem hasn't resolved yet we don't think we have hit that one special thing just yet...lol. We would very much like to smoke test the whole fuel system though as it is a well known fault that the fuel systems on these go wrong and lead to EVAP system leaks... On that note we have also tested the EVAP Purge valve with a battery current and it opens and closes just fine, we've also replaced the Solenoid and DPFE etc. Checked and cleaned out the Charcole canisters etc etc... Replaced fuel cap, checked neck of filler hose for cracks and saw none but that doesn't mean they aren't there and without smoke it's hard to tell... Also there is a valve on the top of the gas tank (green in colour) that seems to be a one way valve... currently that let's a little air in the wrong way and we've wondered if this could be the reason why we don't have any noticable tank pressure (no hiss when you release the cap)... thoughts anyone?

 

[kristykai]

[MENTION=17822]Turdle[/MENTION].... We tested the whole harness when the engine was last pulled down for continuty using a multimetre but that doesn't tell us if there are shorts just breakages... That said all of the injector power connectors have been replaced at the time we pulled down the engine and soldered (very very carefully) back together then restested. Not sure what you mean by the "O v" side (could you explain that one).

Certainly sounds like a feasable idea and if you could give us a bit of an idea of how to test for this we will go straight to it this weekend when trying the rest of the great idea's you have all put forward.... =)

Yes the computer is mounted in the Firewall on the left side of the vehicle (drivers side for the U.S.)

If your interested have a look at these two video's we made when we claimed on the faulty Alternator/Generator from TYC Genera... They sort of show the location of the Alterator to Injector wiring.... Assume it might be different on U.S. models but it doesn't look like the Injector harness comes near the Alternator harness but we could be wrong without having it right in front of us now (currently having lunch at work).

http://www.youtube.com/watch?v=8UNsDWf6gEs

http://www.youtube.com/watch?v=iobMS3CdwcY

Will make sure to take some video of us trying all your idea's this weekend and upload to YouTube to help others with diagnostics and also just to show you all what we have done so if we are doing anything wrong you can correct us =).

Thanks again for all your idea's keep em coming as we have two days worth of hunting to check all these things and report back...