Here we go again!

[stmitch]

I know mine has an issue with the TPS, and as I said earlier it drives totally fine most of the time. The only issues I ever see, are an occasional hard-to-start, caused by over fueling on shut down. Mine seems to do it more while hot than cold, which sounds a bit different from your issue, but don't dismiss a fluky TPS just because the truck drives normally most of the time.

Also, if you're going to replace the plugs, don't waste your money buying fancy platinum ones. Most 3.0 owners have far fewer issues with boring, cheap, copper Autolite 103s or the Motorcraft equivalent. It's what the owner's manual calls for. Just make sure they're gapped properly. Adding fancy plugs will just make one more potential contributor to your running problems.

 

[JP02XLT]

There is also a coolant temperature sending unit that tells the ECU the temp of the engine, This is not the gauge sending unit.

Have you checked the fuel pressure with a gage? and have those numbers for both hot and cold scenarios

JP02XLT

 

[cbxer55]

There is also a coolant temperature sending unit that tells the ECU the temp of the engine, This is not the gauge sending unit.

Have you checked the fuel pressure with a gage? and have those numbers for both hot and cold scenarios

JP02XLT

Where would that sending unit be located? I've changed the one below the TPS once already, thought they were one-and-the-same. Didn't know there was a second one. That could be the culprit, since this seems to be a temperature related problem. The sending unit under the TPS, comes from the same harness. But it's probably the gauge sending unit. Don't know! ;-(

Yes, fuel pressure is spot-on, cold or hot, engine running or key-on, engine off. 62 psi, right smack in the middle of the required range. I have the gauge semi permanently installed for the time being, tie-wrapped to the upper radiator hose to keep it from wiggling around when driving. When I get this all figured out, I'll remove it. Brand new fuel pump and filter as of December.

 

[cbxer55]

I know mine has an issue with the TPS, and as I said earlier it drives totally fine most of the time. The only issues I ever see, are an occasional hard-to-start, caused by over fueling on shut down. Mine seems to do it more while hot than cold, which sounds a bit different from your issue, but don't dismiss a fluky TPS just because the truck drives normally most of the time.

Also, if you're going to replace the plugs, don't waste your money buying fancy platinum ones. Most 3.0 owners have far fewer issues with boring, cheap, copper Autolite 103s or the Motorcraft equivalent. It's what the owner's manual calls for. Just make sure they're gapped properly. Adding fancy plugs will just make one more potential contributor to your running problems.

I will change the TPS out, since I am now aware it has a lifetime warranty.

As for plugs, this truck burned through a set of Bosch iridium of the proper heat range in less than 5000 miles, center electrodes completely vanished. The E-3's that are in there now have been there about 10,000 miles. It's possible at least the passenger side ones don't have center electrodes anymore. Don't know why, but the passenger side plugs erode faster than the driver's side.

Back in 2009, when I was having this problem and never figured out what was wrong, I put in some Autolite double platinums. They were in the truck from 2009 until last year, and still looked fine. I only changed them because they were old. Maybe I shouldn't have! LOL

 

[JP02XLT]

The temp sender unit for the ECU is located in lower intake manifold near the upper radiator hose outlet

Your fuel pressures are good, it has got to be something is not trigeering the injectors, does it always fire immediately on the ether when it does not start?

JP02XLT

 

[lil_Blue_Ford]

Don't remember exactly where the temp sensor is. The one that goes to the gauge has a single wire, the one to the computer has a couple wires. Should be somewhere on the lower intake, IIRC


Sent from my kite using a trebuchet

 

[cbxer55]

The temp sender unit for the ECU is located in lower intake manifold near the upper radiator hose outlet

Your fuel pressures are good, it has got to be something is not trigeering the injectors, does it always fire immediately on the ether when it does not start?

JP02XLT

That's the one I changed. The wires for it are in the same harness as the DPFE and the IAC.

Yes, when I hose it down with ether, it fires immediately. Under the hood, that fuel pressure gauge has a pressure relief button with a hose. I attached the hose to a small piece of tubing glued into the throttle body forward of the blade. I usually keep it capped, but I also use it to squirt the ether into the manifold. The hose from the fuel gauge goes to that as well. Once I get it started on ether, I can run around to the front and push that button, supplying fuel to the manifold. It runs on that really good. Soon as I let go of the button, it stalls. You get the picture of that? Supplying fuel to the manifold in front of the throttle body, via a hose from the fuel pressure gauge pressure relief function.

It was while doing this today, that it started running on it's own. Just, all of the sudden, the sound changed. Something clicked, rather loudly. Engine got smoother. I let go of the button and it was running on it's own. Don't know what clicked, but as I said, when it's warmed up it runs beautifully. FREAKING WEIRD!!!!!!!!!!!!!!!!!!!!

I wonder if that something that clicked was that coolant sending unit? All I know, back in 2009 when I had this same problem, changing that sending unit did nothing. Changing the TPS did nothing. Changing the IAC did nothing. Changing the coils did nothing. Changing the plugs did nothing. Changing the IAT did nothing. Nothing fixed it. I bought the Lightning, put the ranger to pasture and forgot about it. My sister asked about it, I said "if you can get it running, have at it". Gave her the keys, it started right up. She drove it for four years, trouble-free. Maybe it just doesn't like males? ;-)

 

[aspevacek]

You are burning plugs up, you state the Fuel pressure is good. Have you had the injectors put on a flow bench. I would think the burning of the center electrodes would be kind of related to a lean condition. Ie injectors not dumping proper amount of fuel to the cylinders. It is possible there is shit on the passenger side of the rail maybe even some clogging of the injectors. I have not looked at a 3.0 in a good while but I know on the 4.0 the end of line and return are on the passenger side.

I would have been looking at injectors long before now with all the issues you are having with plugs.

 

[cbxer55]

You are burning plugs up, you state the Fuel pressure is good. Have you had the injectors put on a flow bench. I would think the burning of the center electrodes would be kind of related to a lean condition. Ie injectors not dumping proper amount of fuel to the cylinders. It is possible there is shit on the passenger side of the rail maybe even some clogging of the injectors. I have not looked at a 3.0 in a good while but I know on the 4.0 the end of line and return are on the passenger side.

I would have been looking at injectors long before now with all the issues you are having with plugs.

Only certain types of plugs. I put a set of Auto Lite double platinums in in late 2009, and they were still good when I changed them in April last year. As I said, I am going to remove the plugs that are in it now, and see what they look like. Also, as I said, it's been running fantastically since I got it back in late 2013. This problem only cropped up last week. And also, as was stated, when it's running it runs freaking great! I mean, it revs to the moon and back.

I put the chip back in to see what would happen. It ups the fuel flow, ups the timing and ups the transmission shift points. Was out driving today, and it runs frikkin awesome. I was loving every minute of it.

When I shut it off, it re-started five minutes later. It started again 15 minutes after that. At 30 minutes it took two turns to get it going. Drove my Lightning to work today. I'll try it again when I get home, see what happens.

It's a big improvement from Sunday, when it wouldn't start after a five minute stop to get gas.

It's just a cold starting issue. When the temp gauge is showing warm, it starts up. As it gets colder, it gets progressively harder to start, until it won't.

 

[JP02XLT]

A way to cycle the injector to its limit is to pull the electrical connection off while the truck is running / idleing, as you do eash cylinder it should idle rough/miss until you plug the connector back on, this will tell you an indication of how the injector is passing fuel on that cylinder.

Sometimes this can help to disloge crap from the injector tip, a sort of self cleaning, You might give this a try, its ok to cycle the injector connector on and off 4 -5 times on each injector. That might give you some insight on what its doing and as you put the connector back on you should feel a slight thump from the injector working.

As for plugs my Dad has a 2000 Ranger, 2.5 4cyl with 2 plugs for each cylinder, he has had it for 3 years now and it was not a well maintained vehicle when he bought it, anyway it ran good and got good mileage so we left it alone while fixing other issues.

The other day we pulled a plug just for grins and the center electrode was worn down from a single platinum plug style tip, to what looked like a fine wire platinum plug, the gap was almost .120, still it ran good, but was difficult to start on cold mornings (20 degrees or so) but always started.

So we put plugs and wires on it, these may have been original we have no idea on actual mileage, but the plugs we took out were shot, both the center electrod and the grounding tab. They were Motorcraft brand.

JP02XLT

 

[cbxer55]

It's amazing how some engines will run on plugs that look terrible. When I mentioned the truck eating the center electrodes off some iridium plugs, it still ran and ran good. Like you said, difficult starting.

Years ago, when I was married, my wife had a 98 V-6 Taurus, DOHC. I kept putting off doing the plugs, due to my hatred of front wheel drive, side mounted engines, and the difficulty of doing the back three.

Anyway, I finally decided to pay someone to do that crap. It had like 160,000 miles on it, still started and ran fine. Gaps were well over .120 on the plugs, damn near 18 inch. Hellfire, the check engine light never even came on.

I'm going to at least look at them, because I'm curious to see how the E-3's fared over the last 9 months. I was leery of them, as I am most multi electrode plugs. Didn't care for Split Fire plugs at all. If they still look good, I'll stick em back in. If not, I'll change them just for the sake of it.

 

[cbxer55]

Got home last night and tried starting it. It was fortunate I had it on a battery charger, took over 15 minutes of cranking to get it running. When it did start, it was on 3 cylinders. After a few minutes another kicked in. Then I got the Check Engine light for misfire on 4 and 5. Cleared them and let it run, another cylinder kicked in and I got the CE light for misfire on 4 only. Cleared it and after a few minutes it was purring like a kitten. No codes after a 20 minute drive. Started after 5, 15 and 30 minutes. Wouldn't start this morning.

Tuesday morning the misfire codes were for 1 and 5. So it's not consistent on which cylinders are misfiring prior to warming up.

So it's something that's happening when it's cold. While warm it starts right up.

Really starting to believe it's the computer. Will still put in new plugs and the new cam sensor when I get it Friday. Probably won't do anything. But one can hope.

For those who say it's the injectors, and running lean is causing the plug problems. Why don't I have P0171/P0174 codes if that's the case? I had them, but a new fuel pump took care of that problem. Pump only just went bad in December 2016, it wasn't a long term problem.

 

[cbxer55]

Well, having run out of all ideas, and truck still won't start without assistance from starting fluid, I'm going to go ahead and get a new computer. It appears a local O'Reilly's a few miles away can get them for around $150.00 or so.

Don't know what else to do. It runs fine when fuel is pumped directly into the manifold, responds to throttle, and has no defect codes when warmed up, monitors all in READY mode.

It's nuts. The last gasp, so to speak. If a computer doesn't fix it, it's outta here. I'll gladly pay a tow truck to haul it to a junk yard.

 

[cbxer55]

Got a new PCM, but I have to wait until Monday to get it flashed. Then I'll see what happens. If this doesn't fix it, truck is gone. Free ride to the bone yard. I'm sick of dealing with it.

 

[JP02XLT]

Did the PCM swap fix it?

JP02XLT