03 4.6… noise. Not good

In reply to Slippery :

Yep. Took a moment and checked everything out. It's definitely not the compressor. I tried to add a bit of Freon (later) but it's ok, so it's the pressure switch. 
The cycling is causing the engine rattle to come ad go, as the load on belt changes. But with zero load ( belt completely off) the rattle is full time. So it's definitely in the front v of engine, not acceroies or compressor. 
Two separate issues, with one slightly affecting the other 

After it cools off some more, I'll try to head home... and hope the rattle doesn't have a come apart!

In reply to 11GTCS :

Is the LP switch the one on the accumulator? Only other switch I see is on part of heater box enclosure 

I'd take a good look at the harmonic balancer and pulley.  

Since the noise is full time with the belt off, it sounds like the accessories apply enough load to stop the rattle, but when  the compressor cycles the load changes and it take a few seconds for everything to each equilibrium again. 
 

In reply to No Time :

I'm so stressed with new job paperwork, and car, I missed that. I think you may have won the kuipie doll for this game!!!

I sure hope so, and symptoms add up to that!

In reply to 03Panther :

I had a cheat sheet, I replaced the balancer on my pickup in a hotel parking lot last spring because the rubber failed and the was rattling against the timing cover.  

In reply to 03Panther :

Possibly, it would be on the suction side of the evaporator somewhere.   Just a thought, a lot of things can cause low suction pressure so make sure you’ve got the interior fan running above low speed / good airflow through the vents. 

In reply to 11GTCS :

Thanks. I do. I forgot I had checked Freon a month ago, and knew it was ok. Didn't think of switch at time, cause not really driving it and ac is cold enough when I do. As soon as ya said it , I knew. Just not doing well this summer! Forgot I was smart enough to replace that switch, all by myself. 

In reply to No Time :

Yep. It rattling against the cover describes  it to a T

Car made it home no issues; rattling 100% of time when I stoped to swap for truck. But I'll look at it more Thursday. 
Shoulda gotten Paul's moms car - but then I was about third in line when I saw it, and thought my drivetrain was the least of my worries. 
Probably need to put  the head gasket on my Astro... if cyl ain't rusted too bad from steam in combustion side! Better tow pig for contract work, than a car that's still kinda nice. 

Financial Manager tells me I'm not going to put the Astro back on the road. Period. Might look at another Panther, but am going to use the expensive to drive diesel 350 FX4 for this season. At least I can throw a bike in the bed, to save some commuting costs. 

After the long drive, I'm more convinced timing chain, but am going to order a harmonic damper, and I'll get the timing kit as well... if the damper does fix it, I'll have the parts for later. 
Was surprised the kit does not come with gaskets. The gasket kit is a few more dollars, but not bad.  Looks like just cover gaskets and a seal. 
Aside from cover and seals (I'm getting a repair sleeve just in case) are there any other gaskets needed? 
Mine already has the improved intake (helps prevent cracks) - are there things worth doing while in there? I've never worked on any of fords "newfangled" engines! The so called mod-motors. 
Thanks!

Is it a rattle or a tick?  The exhaust manifold studs break off causing exhaust leaks that can mimic the sounds of more catastrophic problems.

wae said:

Is it a rattle or a tick?  The exhaust manifold studs break off causing exhaust leaks that can mimic the sounds of more catastrophic problems.

In my experience the ticking goes away or at least gets quieter once the engine is hot.  My Ford V10 has a bunch of broken studs right now, and I haven't worked up the gumption to fix them.

In reply to wae :

Thanks. Definitely not exhaust. Very much of a mechanical rattle. Like either a alt. bearing about to explode any second, with 1/4" play, or ac compressor as bad. But it ain't them. I've heard valve train noises this bad (about to come apart) but it's not that. The noise (without putting a stethoscope  on it, and ya know how nieces can fool ya) it sound like it's dead center of the v, directly under the alt. Sounds too high in engine bay to be harmonic balancer, but very well could be that hitting the timing cover. Could be as simple as failed factory plastic hyd. tensioners , or guides (due to failing tensioners. 
 

I've seen engines rebuilt over exhaust tic, and also over a hairline crack in a flex plate. Noises are the worst troubleshooting tools, sometimes. But sometimes all we got!

During the 5 hr drive, with ac working due to a relatively cool night, the rattle was there 100 % of the time. 
I just picked it up to drive the 5 miles to my house... mostly to put gas in it to turn my receipts in to co. 
From cold start - no rattle. I left ac off (but remember, it's 100% not the ac clutch or compressor.) and the rattle never started. If I were to start the ac, the rattle would approx. follow the clutch cycling. But if I then turn the ac OFF, the rattle continues on exact same cycle 

and rattle is not rpm dependent. 

Fortunatly, I can drive my expensive to use F350, instead of rushing the job, or having to pay a parts changer to throw expensive parts at it till he accidentally finds the right one. 

Can you see the belt tensioner when it is making the noise?  

Not that these engines are known for tensioner issues or anything...

In reply to Pete. (l33t FS) :

When the rattle was coming on for 3-4 seconds, and off for 12-13, at idle, I stopped the engine, took belt off, and restarted the engine. Same rattle still there, but "on" 100%.  led me to believe that is was not one of the accessories. I did check all the pulleys while off, seem ok as well. 

When I put the belt back on, and was watching, I noticed the ac clutch cycling. Wham clutch came on, 1 1/2 seconds later (due to load?) the rattle would start for 3-4 seconds, then stop. Several seconds later ( clutch still on) would stop. Several seconds, clutch stopped (still no rattle). Few more seconds, clutch kicks on, start timing over. Clockwork. 
Turn ac off, rattle would continue same cycle. That's where I get confused!

when I hear rattle I think timing chains, especially on the 4.6, they are kinda notorious for it.   Its not the funnest job in the world but it is a diy.  I was able to do it in about 8 hours with a lunch break last time I did it.  YMMV based on stuck parts etc (although last time I did it was on the rustiest northead panther ever) 

Pete. (l33t FS) said:

Can you see the belt tensioner when it is making the noise?  

Not that these engines are known for tensioner issues or anything...

 

Not sure the belt tensioner on these  is more troublesome than others. I did read the timing chain tensioners definitely are! Factory is plastic body, oil pressure actuated, no gasket. Cheap seal fails, they don't hold chain tight, and wears out the guides, chain gets super loose, and cam timing goes all over the map!

China timing kit, $95. Chain sprockets, guides, plastic tensioners. 
melling or cloyes - 200 to 600. Metal only few more dollars than plastic. 
If I can find just chain and guides, in quality, for 100 to 150, performance tensioners the have a ratcheting function, are $133. 
Prolly have to get whole kit from cloyes, then replace their nice metal ones, with the $133 ones. 

In reply to JThw8 :

That's about where I'm at. Might not need the chain and sprockets, but while I'm in there i think it's best. Glad I'm in no hurry, now. 
The comes and goes part is really stressing my mind. 

If I can relax, order the parts, do it over the winter, I think all will be good!!!

03Panther said:

In reply to JThw8 :

That's about where I'm at. Might not need the chain and sprockets, but while I'm in there i think it's best. Glad I'm in no hurry, now. 
The comes and goes part is really stressing my mind. 

If I can relax, order the parts, do it over the winter, I think all will be good!!!

Agreed the sporadic nature has me confused.  Ive never bothered with the chains and sprockets as they are usually good, just the tensioners and guides, those are the weak spots.   It makes the job go quicker, you can lock the chains in place with some zip ties and pull tensioners and guides without removing and retiming the whole motor.  

Since I'm only at 112k miles, and most of its oil changes (and all other maint) have been on time and quality oil and parts ( I've, unfortunately, let it get a bit long twice in last two years) I think I'll take a chance on upgraded tensioners and guides. I'll order whole nine yards, for next time in; plan ahead for 200K + 

I'd love it if I get to see 300K on this odometer. I've been primary driver on this one since 35K. 

Found a few shots I took of the last one I did.  It was an 03 as well with right around the same miles (120k or so)

Old guide vs new

Detroyed tensioner (that should be flat across the top)

zip tying the chains to keep everything timed while its apart