Repair or cash it in??

[Kidd7]

I've got a '99 Ex 4.0 SOHC 2wd ~160K; owned for about 2.5 yrs. Repairs: Plugs, wires, Coil pack, crank position sensor, throttle postition sensor, MAF, PCV, fuel pump, steering rack, rebuilt tranny. plus suspension, brakes, oil changes, etc.
It's still shifting funny. My tranny guy mane some adjustments and informed me that 1-2-3 have a misfire. In my research so far the 2 most likely causes are intake gaskets or timing chain slippage. I plan to do a compression test when cold & then hot to compare, this should rule out chain vs. gasket. Overall the truck is in great shape.

I'd like some input from people that have had these SOHCs fix or move on???

Thank ya'll
I've read this thread and it gives good opinions:
4.0L SOHC to 4.0L OHV Pushrod Swap?

 

[shucker1]

I have the 5.0 so I may be out of line.

Most members I read about like the SOHC due to the power advantage over the OHV but the SOHC is a pain to repair the timing chains.

If I am correct the engine or transmission has to come out to do the chains on the SOHC engine.

It all depends on what the truck means to you and the body condition.

I would say fix it before anymore damage is done and keep driving it but that just me.

 

[J_C]

Are you saying your transmission guy made adjustments and it's still shifting funny so he's claiming the cause is misfires, or that he fixed the shifting AND told you there are misfires?

If there are misfires and you get those fixed but it still shifts funny, is he going to bill again to fix the tranny or not? Is it under warranty or he has some obligation written or implied?

How is doing a compression test hot vs cold going to tell you if it's timing vs intake gaskets? I could see there being some difference if we were talking about a head gasket.

Does it make a lot of timing chain rattle? If not then I doubt it has slipped. Grab an OBDII scan tool capable of live data and look at the fuel trims. If rich, then check compression. If good compression, look around for vac leaks and if none are found, change the intake gaskets. Of course you should also check for OBDII set codes and pending codes while the scan tool is hooked up.

Fix it or move on, "could" depend on what's really wrong and if the tranny shifting is fixed, cheaply fixable, or not too bad and you can live with it... total necessary repair costs.

If everything else is good, then I'd look at what else you can do with ~ $2500. If it needs timing components and you can't get anything else you want more, including the state of repair since you've already done a lot of things that should last a while, then it could make sense to pull the engine and put timing components on even if you have to pay someone else to do it.

Another option is shop around for one with a V8. If it's not urgent then you have some time to find one. I mean if you didn't know it had misfires until the tranny guy told you then it must not be running too bad, becomes more a matter of how long it can run with minor misfires before it destroys the catalytic converter, and getting worse fuel economy.

 

[Kidd7]

He adjusted the 5th gear band tension and stated he saw the misfires in his scan tool. Our tranny guy has been real good, no charges and its out of warranty. I was thinking hot vs cold cuz I read somewhere that the intake gaskets will expand with heat and can in essence seal back up. She idles worse when cold. I don't notice any rattle at start up or while driving. It does seem to shift and run better once its hot. The tranny guy did state the misfires could cause it to shift differently and will eventually affect the torque converter. Which is entirely possible depending on the algorithm the ECU uses to determine shift points. I do see your point about the head gasket verse intake gaskets, the intake gaskets are beyond the valves, compression testing will not check those at all.
Would smoking the intake or bowing propane around the intake give me a clue on the intake gaskets?

 

[J_C]

^ Engine warming up and closing an intake gasket leak can happen, but it won't necessarily happen. Smoking the intake, propane, starting fluid, water spray, etc can find a leak but that's not guaranteed either. I would look at fuel trims with a scan tool. If it's leaking they're going to go up.

Intake gasket leak IS likely, but I would look everything else over, pinch or plug hoses or intake ports to try to narrow it down since most other vac leaks are easier and cheaper.

 

[Kidd7]

I did test with propane a while back and had my mechanic smoke it when I thought I had a leak and it turned up nothing. I still don't like the shifting through 2nd gear, but it is better. It seems to stay in 1st too long then shift through 2nd quickly. But overall is runs good. I'll do some datalogging this weekend and see what I come up with.

 

[Kidd7]

High fuel trims will be my major inductor then? Showing that un metered air is entering.when should I start to worry about timing chains? Wait for the noise or should I be more proactive? I've got 150k with these chains, I'd be happy with another 150k.

 

[shucker1]

Don't think you will get another 150 K out of the chains you have.

To me it's better to be proactive than reactive......

High fuel trims will be my major inductor then? Showing that un metered air is entering.

Highly probable.

 

[imp]

I have the 5.0 so I may be out of line.

Most members I read about like the SOHC due to the power advantage over the OHV but the SOHC is a pain to repair the timing chains.

If I am correct the engine or transmission has to come out to do the chains on the SOHC engine.

It all depends on what the truck means to you and the body condition.

I would say fix it before anymore damage is done and keep driving it but that just me.

@shucker1
Agreed, and understood! imp

 

[Centaurus5.0]

2001 5.0L 2WD MERCURY MOUNTAINEER PREMIER 130,000 miles

$1899

2001 MERCURY MOUNTAINEER PREMIER




Just saying...

 

[Kidd7]

@ Centaurus5.0; yup. ... just wish that wasn't on the other side of the country.
@shucker1 I was saying if i replace the chains and get another 150k, I'd be ok with that.

 

[koda2000]

2001 5.0L 2WD MERCURY MOUNTAINEER PREMIER 130,000 miles

$1899

2001 MERCURY MOUNTAINEER PREMIER




Just saying...

Man, ones like that (condition and miles) are super rare these days. At that price I'd be tempted to scoop that one up, though I certainly don't need it.

 

[shucker1]

@Kidd7

Sorry Brother,

Speed reading again!

LOL

 

[J_C]

Wait for the noise or should I be more proactive? I've got 150k with these chains, I'd be happy with another 150k.

No need to do it until you have noise. If it follows the typical pattern the noise will begin at cold startup and progressively get worse. Edit: I mean get worse over weeks/months/years, not as the engine warms up.

 

[imp]

Man, ones like that (condition and miles) are super rare these days. At that price I'd be tempted to scoop that one up, though I certainly don't need it.

@koda2000
The 5.0 is what ought to sell it! imp

 

[Mbrooks420]

I’d buy that 5.0 in a second if it were local.

 

[koda2000]

@koda2000
The 5.0 is what ought to sell it! imp

Absolutely. I would never own another SOHC, not even if it only had 60K on it.

 

[Mbrooks420]

I like the ‘custom’ wheels. Custom must mean older. I’d still buy it, today.

 

[Kidd7]

This is my wife's DD, we use it for the family on the weekends, but I don't drove it regularly. I looked at some stuff last night and datalogged on a short run to home depot to do some plumbing. The fuel trims were at 0. There are no codes or pending codes. I still need to dig through the log. I also drove it this morning and paid a little more attention. There is a slight whine when it first starts, goes away in maybe 30 seconds and it has a rough idle. I don't hear what I would call chain slapping around.
I guess now I'm looking for some advice on troubleshooting to diagnose this. Then I can decide if it's C4 or chains or gaskets. Thanks ya'll.

 

[koda2000]

If you timing chains aren't rattling yet, consider yourself lucky. Leave it alone until they do. It'll give you plenty of notice, beginning with noise at cold startup and progressing to rattling like a diesel truck. Messing with the TC's "proactively" could do more harm than good.