Totally stumped

[Turdle]

No correlation between compression variation and the glowing exhaust.

I will be ordering a new ECM today. Hope that's it.

whoa!!
back up a minute-

Does the check engine light come on when you switch the key to on?

Does it switch off when fuel pump stops priming? If so-I think that means the PCM has passed it's self test.
Are you absolutely positive you installed the Cam sensor properly? You do know the TDC mark on the crank pulley lines up 2 times for every 1 revolution of the camshaft? ( some guys have a hard time understanding this-which is why I asked)

Also-the glowing red exhaust, and low compression are a definite thing to look in to. If your compression tester aint working-you better get one that does-
I have no issues at all threading mine into my v8 spark plug holes

If this engine gets into a lean condition-bank 1 will suffer the most damage-and the bank 1 cat will glow --(don't ask how I know)
Just suffice it to say I have seen it.

Another thing-now this is a long shot---

I had a heckova time getting my truck running a few months ago-I mean it wasn't doing squatt--

I changed the oil and it fired right up------

There is a oil sending unit-it is merely an on off switch.
While cranking, does the oil pressure gauge come right up, or does it seem to stick, and then jump--
This could be a clue. I think the ignition is killed if the oil pressure sender is faulty----

 

[og]

whoa!!
back up a minute-

Does the check engine light come on when you switch the key to on?

After a few seconds, yes.

Does it switch off when fuel pump stops priming? If so-I think that means the PCM has passed it's self test.

Don't know for sure

Are you absolutely positive you installed the Cam sensor properly? You do know the TDC mark on the crank pulley lines up 2 times for every 1 revolution of the camshaft? ( some guys have a hard time understanding this-which is why I asked)

I have not removed the mechanism, only the switch, it is impossible to improperly install the switch.

Also-the glowing red exhaust, and low compression are a definite thing to look in to. If your compression tester aint working-you better get one that does-
I have no issues at all threading mine into my v8 spark plug holes

THe engine has metal shields around several (but not all) of the spark plug holes. On these, it is impossible to get a socket onto the compression gauge fittings. Hence, they cannot be properly tightened. And on these (rear two plugs only, 3,4,7, and 8) I cannot get the fitting tight. Therefore I got lower compression readings. I'm fairly convinced that there is not a dramatic difference in compression.

If this engine gets into a lean condition-bank 1 will suffer the most damage-and the bank 1 cat will glow --(don't ask how I know)
Just suffice it to say I have seen it.

The cat is not glowing, THe exhaust manifold glowed- but I only SAW it on one side. Bright sun on the other side, so it may have been glowing there too. The cat on that side does show some sign of having gotten warmer. The lean condition does make some sense.

Another thing-now this is a long shot---

I had a heckova time getting my truck running a few months ago-I mean it wasn't doing squatt-- I changed the oil and it fired right up------

There is a oil sending unit-it is merely an on off switch.
While cranking, does the oil pressure gauge come right up, or does it seem to stick, and then jump--
This could be a clue. I think the ignition is killed if the oil pressure sender is faulty---

Thanks, I'll check that- but this vehicle has had new Mobil 1 every 10,000 miles since new, I have the oil analyzed every oil change and it's always been OK, and the gauge does jump right to pressure when cranked. But I will dang sure check the sending unit.

I just found out I need to have the car at a dealer to program the PATS when I start this thing with the new ECM. Anyone have suggestions for that? Or does it require a lot of folderol?

 

[DuncanOfEngland]

OG,

I had an Explorer in my workshop recently with glowing manifolds and compression variation. I replaced both heads and the engine ran fine.

Duncan

 

[Turdle]

The metal sleeves have a slot-squeeze them together a bit with some channel locks and they will wiggle out like a loose tooth-
be careful though-you'll need to slide them back in. I just had to on my son's NY rusted Mounty friday-so I know they come out.

 

[410Fortune]

288,000 miles
will not run

It was running (very poorly) when you took it in for exhaust work correct?
Now after new exhaust it does not run?

No codes?

I would check the compression after removing the heat guards
I would swap the computer out with a similar unit, same year is a MUST and see if it runs

When you had your exhaust done you should have removed the rear secondary cat converters, you only need the primary cats in the down pipes to pass emissions.
Do you still have the secondary cat converters?
Did the exhaust shop do a flow test for you? I know you say the exhaust is all new manifolds back, just want to verify this as th eblockage could be in the factory secondary cats or factory mufflers. The factory exhaust on these trucks is a mess

Also check the fuel pressure again, ensure the fuel rail is getting pressurized when you turn the key. In my experience these fuel rails DO bleed down back to the tank.
I have read and been told that the fuel rail is supossed to hold pressure in our 95-97 trucks even if it sits for days. Not one of the Gen II trucks I have worked on or work on often will hold pressure. It slowly bleeds down right after shutting the engine off.
All of them run fine and have fine fuel pressure. I think its a myth

My BII used to hold fuel pressure when I had the 4.0L OHV in there, now with the GT-40P 5.0L and OBD-II system it bleeds down same fuel pump (88 BII).

I have had a clogged cat converter on my truck, the catalyst broke loose inside the converter housing, chunks were pressed up against the pipe at the rear...it was HARD to diagnose, it would run fine for a bit then bog horribly.
I found the problem (this was a new high flow aftermarket cat, 3 months old) by listening VERY carefully under the truck with it running and in gear.

I have had a computer go bad in my truck, no codes were present, then there were many codes present after fussing with it for a couple of months (throwing parts at it)
Computer passed self test, engine barely ran
Computer was fried, exhaust shop left the key in the ON position and proceeded to use a MIG on my exhaust. This fried my PCM
new PCM from Advance Auto $60 and it ran perfect from then on.
I could actually smell electrical burning smell in my PCM

I have also seen personally 4 Ford PCM's completely fail, all of them OHV 4.0L's (OBD-I, getting older) all of them engine would run very poorly, make no power, barely idle. One of them ran okay but some driveability issues with EGR and 02 sensor codes.
Computer issues can be tricky to find, UNLESS you just swap the PCM with one with the SAME CALIBRATION CODE
This eliminates the PCM as the fault and you can move on

Check your wiring plugs
All that messing around you have done in your engine bay, intakes, etc...the factory wiring is very tight, it must be routed properly or it can get pinched/burned/loose and cause all sorts of issues difficult to locate

John may be onto something with the crank sensor as well, they are known to give fits, especially with a no start issue after a very poor running issue


As for the PCM problem, I usually borrow one from another truck or friend if possible before I go buying parts. Junk yards have known good PCM's for $60 around here, do not pay Ford $350 for a remand unit IMO.

Good luck and keep us posted

 

[Turdle]

I have read and been told that the fuel rail is supossed to hold pressure in our 95-97 trucks even if it sits for days. Not one of the Gen II trucks I have worked on or work on often will hold pressure. It slowly bleeds down right after shutting the engine off.
All of them run fine and have fine fuel pressure. I think its a myth .

I'm glad you said that-mine does also. I seem to remember discussing this at length-

Good to see you pop in Jamie--

 

[og]

288,000 miles
will not run

It was running (very poorly) when you took it in for exhaust work correct?
Now after new exhaust it does not run?

No, I drove it hjome after exhaust work. It ran, poorly, but it ran.

Only after parking it in the garage did it cease to start.

No codes?

No codes.

I would check the compression after removing the heat guards

I may yet do this, but the engine would run at least try to start if compression, spark and fuel arrived at the proper times. It does not.

I would swap the computer out with a similar unit, same year is a MUST and see if it runs

$140 at the yard. And *I'm being told without the keys it won't work ANYWAY.

When you had your exhaust done you should have removed the rear secondary cat converters, you only need the primary cats in the down pipes to pass emissions.

I just wantede this to be "as stock"

Do you still have the secondary cat converters?
Did the exhaust shop do a flow test for you? I know you say the exhaust is all new manifolds back, just want to verify this as th eblockage could be in the factory secondary cats or factory mufflers. The factory exhaust on these trucks is a mess

They cut it up and threw it away.

Also check the fuel pressure again, ensure the fuel rail is getting pressurized when you turn the key. In my experience these fuel rails DO bleed down back to the tank.

Pumps to 45 psi and stays right there. Key off, it will hold 45 PSI for hours and hours.

I have read and been told that the fuel rail is supossed to hold pressure in our 95-97 trucks even if it sits for days. Not one of the Gen II trucks I have worked on or work on often will hold pressure. It slowly bleeds down right after shutting the engine off.
All of them run fine and have fine fuel pressure. I think its a myth

yeah, I think in replacing the pump I just cost myself $95 and a lot of grief. I think the old one was probably fine.

My BII used to hold fuel pressure when I had the 4.0L OHV in there, now with the GT-40P 5.0L and OBD-II system it bleeds down same fuel pump (88 BII).

I DID take the fuel bypass dashpot off and confirm it was sealing. I think this helped.

I have had a clogged cat converter on my truck, the catalyst broke loose inside the converter housing, chunks were pressed up against the pipe at the rear...it was HARD to diagnose, it would run fine for a bit then bog horribly.
I found the problem (this was a new high flow aftermarket cat, 3 months old) by listening VERY carefully under the truck with it running and in gear.

I have similar painful experiences with clogged cats. But in every case, the engine would fire and attempt to start. Not here.

I have had a computer go bad in my truck, no codes were present, then there were many codes present after fussing with it for a couple of months (throwing parts at it)
Computer passed self test, engine barely ran
Computer was fried, exhaust shop left the key in the ON position and proceeded to use a MIG on my exhaust. This fried my PCM
new PCM from Advance Auto $60 and it ran perfect from then on.
I could actually smell electrical burning smell in my PCM

I know the shop mig welded on the exhaust. But it did run afterwards. At least long enough to get it home.

I have also seen personally 4 Ford PCM's completely fail, all of them OHV 4.0L's (OBD-I, getting older) all of them engine would run very poorly, make no power, barely idle. One of them ran okay but some driveability issues with EGR and 02 sensor codes.
Computer issues can be tricky to find, UNLESS you just swap the PCM with one with the SAME CALIBRATION CODE
This eliminates the PCM as the fault and you can move on

This is why I'm swapping the ECM. More than one person has told me about rap9idly deteriorating driveability ussues until total non-function. Problem is, now I'm reading about having to flash the ECM with the new PATS info.

Check your wiring plugs
All that messing around you have done in your engine bay, intakes, etc...the factory wiring is very tight, it must be routed properly or it can get pinched/burned/loose and cause all sorts of issues difficult to locate

Plug wires and coil pacs are brand new, and wires are routed exactly as from the factory, even including the accordion pleated steel heatshield.

John may be onto something with the crank sensor as well, they are known to give fits, especially with a no start issue after a very poor running issue

Lord, I hope not. But if I have to I have to.

As for the PCM problem, I usually borrow one from another truck or friend if possible before I go buying parts. Junk yards have known good PCM's for $60 around here, do not pay Ford $350 for a remand unit IMO.

Problem, still, is getting matching keys. Or having to reflash the unit.

Good luck and keep us posted.

Thanks, to all- I appreciate the help, it's been a really frustrating ride.

 

[410Fortune]

Oh yeah PATS, dont be too scared, you can swap the PATS module as well, although it does make it much more difficult to justs "swap" computers with a friend.

You can tape his key to his PATS module, plug it into your harness with his PCM, use your key to turn your starter over, his key taped to the pats module will work (I have seen 5.0L conversions done this way)


Do you know anyone with a 98 5.0L Explorer?

You could tow it to Ford and have it hooked up to a "pin out box" this will test the wiring harness/sensors to ensure everything is at least talking to the PCM. Then Ford could test your computer?
I had to bite that bullet too, ended up $700 at Ford and three weeks later (they didnt want to work on a heavily modified BII, until I actually spoke with the service manager about the trucks history) PCM was fried.

Have you checked all your fuses and the PCM relay??????

 

[og]

But if I don't swap the PATS module, the ECM has to be reflashed? What's with the PATS and ECM?

 

[410Fortune]

Sord of

the PCM and the PATS module must match, meaning come from the same truck
The key must be present for the PATS module to allow the truck to start

So you can borrow a PATS module, PCM, and key from a donor 98 5.0L, plug them into your truck and see if it runs

Does take some work, but not impossible and if you can pull it off its WAY cheaper then using a Ford dealer/tow truck

At least thats how I undersand the 98 Pats system works...

The key just has to be within proximity of the PATS module, you dont have to swap ignition/lock cylinders or anything that extreme

 

[og]

Cancelled the ECM order. I have a guy who is (suposedly) capable of reading all the stuff on the truck, and confirming (for SURE) that the ecm is hosed. So I will be having it towed to him to confirm diagnosis. I wil be confirming wihtn him that he has the ability to make the necesary repairs first, so I don't get too badly soaked.

Sheesh.

 

[Mbrooks420]

Good luck.

 

[og]

Fixed!!!

Ok, for all you who were helpfgul- and believe me, you all helped by helping me think of other things to test/try, I am here to tell you what the final resolution of the trouble was.

I took this to a mechanic who came highly reccomended to me. I tend not to trust anyone with my truck, so this was a big leap of faith.

This guy does all the tests I do, and is equally stumped. In four days, he's throwing up HIS hands and saying "Man, I don't know WHAT the hell is wrong wiht this thing!!!"

So we decided together that the next thing was to rip off the timing cover again, even though we had confirmed that the valves seemed to be opening at the exact correct time. he also had a better compression gauge, and he got these readings:

1: 152
2: 153
3: 152
4: 152

5:152
6:152
7:153
8:152

Those are copied from the printout he gave me.

So I got fuel. I got EXCELLENT compression. I got spark. IN fact, you can hook up a timing light, and the harmonic balancer says it's right where it ought to be.

And then he takes the balancer off.

The harmonic balancer has cracked, and the key has worked it's way around inside the balancer, so the spark is occuring about 32 degrees in advance of it's need. New balancer, and it starts and runs like a top.

New seals and new gaskets, checked the crank for damage and thankfully, had none. Mechanic said the timing chain was flawless. 288,000 miles. Mobil One, folks. It's worth it.

And thanks again for all your suggestions. I hope this helps someone else with a similar problem. THis drove me crazy. And cost me a couple grand, before it was over, in mis-diagnosed parts.

 

[Turdle]

Thanks for updating this OG--

 

[Josh]

My balancer worked its way loose and cracked too. My truck was running like crap for a few days before the balancer bolt snaped and shot into my radiator. Sorry I didnt even think about that.

 

[Provokr]

And cost me a couple grand, before it was over, in mis-diagnosed parts.

On the bright side... at least you know you have almost a brand new truck now...

 

[og]

On the bright side... at least you know you have almost a brand new truck now...

yep. I figure I'll get another 200,000 miles, I hope.

And it's amazing how much power it has, I forgot how ballsy this truck is.

 

[blakshukvw]

So was the balancer wobbly and loose on the crank before you took the bolt out?