At a loss of ideas...

[RedEB]

After having taken a week to replace lower and upper intake manifold O-rings, thermostat housing (w/ thermostat and sensor + sender), primary tensioner, spark plugs, ignition coil, wires, and rear tensioner- my previously running-fine X has taken the dump on me. I have replaced the coil, wires, and spark plugs and even tried brand-spanking new parts to determine if these were the culprits.
Here is the background: 97 SOHC w/ 153K miles. Engine was running well before the operation, chain rattle was evident but not pervasive. Apparent vacuum leak that was audible though no CEL was present. Engine ran a tad rough cold but would smooth out beautifully.
Here is what is currently happening: random misfire on #4 and #5 (according to dealership, no CEL or other computer codes are present). They also stated that #4 and #5 have 6-10% less compression than the other cylinders (insignificant in my book....). Again, No CEL or code is being thrown. It should be noted that I screwed up the firing order when installing new coil and also failed to insert the ground on the coil, so I had many hard starts before finally figuring out the sequence for the screamin' demon pack ( was original, not the sequence mentioned on this website).
I am truly at a loss. Of course, the dealership is screaming, "buy a new engine!!!" But I don't think the engine is dead. It doesn't sound good at idle, but I am still able to get up to 70mph without much effort. It stumbles and misses when confronted with a hill or sudden acceleration. Any ideas?
PCV? intake O-rings (maybe I screwed them up)??? COuld the new rear tensioner have opened a can of worms? This vehicle is our only vehicle- any help would be great!!!

 

[RedEB]

Oh, forgot to mention that I ran a can of seafoam before the operation and burned that all out. It ran fine after that. Could I have gummed up the cat?? I did notice a different smell from the engine, though I can't place a finger on it. It is not gas nor is it coolant....
The engine does stumble at idle with random misfires and is now more sluggish than before.

 

[JoeMahma]

Oh, forgot to mention that I ran a can of seafoam before the operation and burned that all out. It ran fine after that. Could I have gummed up the cat?? I did notice a different smell from the engine, though I can't place a finger on it. It is not gas nor is it coolant....
The engine does stumble at idle with random misfires and is now more sluggish than before.

Have you tried putting your original coil packs back on?

 

[RedEB]

yeah, still same result. Even tried different wires AND different plugs.

 

[RedEB]

Ttt

 

[RedEB]

Just to update:
replaced IAC...no change in poor performance. The X ran great right after replacing lower and upper intake gaskets- but next day it sucked arse!
I did "recharge" my K&N, so I will try to clean the MAF. Otherwise, I just took the upper intake off because the EGR gasket was not completely in the intake, so that may have been a source of a vacuum leak...does the green O-ring enter completely into the intake??? I am really running out of ideas here and I just have a heck of a time swallowing what the dealership said.
Replaced: wires, plugs, coil, IAC...
Thinking about replacing: O2 sensor (but no codes!!!), pcv, fuel injectors, fuel filters....

 

[JoeMahma]

Just to update:
replaced IAC...no change in poor performance. The X ran great right after replacing lower and upper intake gaskets- but next day it sucked arse!
I did "recharge" my K&N, so I will try to clean the MAF. Otherwise, I just took the upper intake off because the EGR gasket was not completely in the intake, so that may have been a source of a vacuum leak...does the green O-ring enter completely into the intake??? I am really running out of ideas here and I just have a heck of a time swallowing what the dealership said.
Replaced: wires, plugs, coil, IAC...
Thinking about replacing: O2 sensor (but no codes!!!), pcv, fuel injectors, fuel filters....

You are sure you didn't miss a vacuum line when putting it all back together? I know it wouldn't have anything to do with the work you did and it would be a big coincidence but has the fuel filter been changed lately? Hope ya figure it out.

 

[RedEB]

You are sure you didn't miss a vacuum line when putting it all back together? I know it wouldn't have anything to do with the work you did and it would be a big coincidence but has the fuel filter been changed lately? Hope ya figure it out.

I replaced the upper intake gaskets because I thought I could hear a "whooshing" sound like air, but there was no vacuum leak evident. Put it all back together and it ran very well for about 1-2 minutes, then I revved it up to 2500 RPM and kabamo- same old deal. misfiring and rough idle, and misfiring under load.
I just bought a fuel filter yesterday and gonna try that in today. Looks like we were in the same mindset on that one.
If this doesn't work, I'm considerin a gasoline soaked towel in the fuel tank cover and a match...might be the best solution.

 

[RedEB]

OK, So I took it for a test drive after checking for vacuum leaks and I FINALLY got a cel on. Unfortunately, the code is P0301- cyl 1 misfire. Soooooo, my question at this point is if it could possibly be a O2 sensor, clogged cat, bad fuel injector. I'm starting to run out of ideas and wondering if the ford dealership was correct in saying that the engine is essentially dead. What is so stranged though is that when I first start the engine, it runs and sounds great for about a minute or so and then the misfire begins. If it were more serious (ie. mechanical failure), wouldn't the misfire be evident on startup immediately?
Could really use some advice on this one.

 

[Firestorm]

They also stated that #4 and #5 have 6-10% less compression than the other cylinders (insignificant in my book....).

I'm with you on this one, even though the rings on these cylinders may be going.

My best advice is to get a fuel pressure gauge hooked up and see what kind of pressure there is. Just because you have a misfire doesn't necesarily mean you're not getting spark. Even though I believe it could be fuel related, have you tried checking for spark?

I'm with you also in that knowing your motor isn't shot.

 

[JoeMahma]

OK, So I took it for a test drive after checking for vacuum leaks and I FINALLY got a cel on. Unfortunately, the code is P0301- cyl 1 misfire. Soooooo, my question at this point is if it could possibly be a O2 sensor, clogged cat, bad fuel injector. I'm starting to run out of ideas and wondering if the ford dealership was correct in saying that the engine is essentially dead. What is so stranged though is that when I first start the engine, it runs and sounds great for about a minute or so and then the misfire begins. If it were more serious (ie. mechanical failure), wouldn't the misfire be evident on startup immediately?
Could really use some advice on this one.

EGR system checks out ok? Also maybe clean the MAF sensor? I don't think your engines shot either. Like you said, it would run like crap hot or cold.

 

[dapp68]

I have the same problem with my 98. Two different dealers say the engine needs to be replaced, yet it starts and runs smooth until it loads up with fuel and dies. It all started with #1 misfire and primary coil mailfunction. Dealer also says compression is down on #5 & #6. Would love to figure this out and prove them wrong but I'm out of ideas.

 

[RedEB]

I'm with you on this one, even though the rings on these cylinders may be going.

My best advice is to get a fuel pressure gauge hooked up and see what kind of pressure there is. Just because you have a misfire doesn't necesarily mean you're not getting spark. Even though I believe it could be fuel related, have you tried checking for spark?

I'm with you also in that knowing your motor isn't shot.

That is quite reassuring to hear someone else agree with me for once! I am going out tonight to get the fuel pressure guage, at the very least it will confirm that the fuel system is OK. Hopefully it will indicate otherwise, but it will help no matter what.
Joemahma- EGR is another system I have yet to check. What is the best way to check if it is faulty?? I am also wondering if it perhaps is a bad catalytic converter. It is possible all the solvents, all the crud from the seafoam treatment and the engine flush I did clogged the cat...
Dapp- Hopefully we get this figured out buddy, sounds like we're in the same boat.

 

[JoeMahma]

That is quite reassuring to hear someone else agree with me for once! I am going out tonight to get the fuel pressure guage, at the very least it will confirm that the fuel system is OK. Hopefully it will indicate otherwise, but it will help no matter what.
Joemahma- EGR is another system I have yet to check. What is the best way to check if it is faulty?? I am also wondering if it perhaps is a bad catalytic converter. It is possible all the solvents, all the crud from the seafoam treatment and the engine flush I did clogged the cat...
Dapp- Hopefully we get this figured out buddy, sounds like we're in the same boat.

EGR system, HMMMMM...first try just unplugging the vacuum line going to the valve and block the line. Drive it and see if it smooths out. If it does you definitely have a problem with it. Check out all hoses and hard lines running to it to make sure there are no leaks. Hook up a vacuum pump to it with the engine running and apply vacuum slowly...the rpm's should go down. If they don,t remove the valve and look for deposits and test it off the truck with the pump to see if it opens. Check the gasket too. Ive never done one on the explorers but they should all be the same basically.

 

[dapp68]

I'm thinking the dealer would rather put a new engine in rather than figure out what's wrong. I wouldn't mind putting in a new engine if I could be sure the problem dosen't transfer over from the old to the new, if you know what I mean. I've tried just about everything. Tore it down to the timing chains, all are tight, new crank and cam sensors, new pcm, new coil, plugs and wires. Dealer says fuel pressure is good though I don't have a gauge to check it. I feel like I'm missing something but don't know what....

 

[Firestorm]

Not saying that it couldn't be a clogged catalytic converter, but generally there is the smell of rotten eggs to go along with it.

EGR system checks out ok? Also maybe clean the MAF sensor? I don't think your engines shot either. Like you said, it would run like crap hot or cold.

This could be another possibility.

Did you ever get to check the pressure at the fuel rail?

Also, our lower compression on cylinders #4 and #5 could cause misfire also. Did they say what the compression was on cylinder #1, or did it check out?

-Nathan.

 

[RedEB]

Not saying that it couldn't be a clogged catalytic converter, but generally there is the smell of rotten eggs to go along with it.



This could be another possibility.

Did you ever get to check the pressure at the fuel rail?

Also, our lower compression on cylinders #4 and #5 could cause misfire also. Did they say what the compression was on cylinder #1, or did it check out?

-Nathan.

Yeah, the fuel pressure at the rail was within spec- 36 psi.
They said the compression on cylinder 1 was OK. I haven't confirmed this myself.
To be blunt, if this were my first ford, it would be my last. THis car is driving me nuts- I'm thinking I would be best to just dump the POS.

 

[JoeMahma]

Did ya figure this out?

 

[RedEB]

Unfortunately no. I just took it to a NAPA and hopefully they will have better equipment at their disposal to figure it all out. I am a third-year dental student, so I was just running out of time to work on it. BUT, my wife and I just bought a 2001 volvo S40 1.9L Turbo so we at least now have another car. Man, those volvos are nice!
I am really hoping that we get the X fixed, but if it does turn out to be internal damage- I'm thinking it might be time to part with the ol' gal ...

 

[RedEB]

So the NAPA guy called me today and said he got it up and running...and sure enough he did! It turned out that the spark plugs on #1 and #4 were defective in that the sleeve around the electrode were loose. Apparently, the sleeve was rocking and blocking the electrode intermittently.
He showed me the plugs and sure enough, his tale was true. He said he has never seen anything like this and suspects they were either dropped in the autoparts store or they were defective...leave it to my luck.
Either way, happy to have the beast back. It does still make a rattle- intermittent raspy noise that I have yet to figure out, but I could care less at this point....she runs great!
Could be a heat shield, exhaust leak.......it doesn't change with the RPMs...OK, so maybe I do wanna figure it out. But at least she's running great.
Thank you all for all your suggestions!