Whats that Rattle?

Pez · Dec 10, 2018

Recently purchased a '04 Ranger with the 2.3L Duratec 5 speed with 164,xxxmiles. Excited to have the fabled Duratec as I have owned a few Lima's, a 3.0 and a couple of 4.0's. But my happiness was crushed the next morning after purchase, I could hear a obvious rattle. I washed the engine at work in prep to fix the valve cover gasket leak and get a visual on the top end. On the way home from work I was disturbed to find it barely running... After some diag I found coil had failed. With that replaced my running has improved greatly and the rattle is much less.

Details on the Rattle:

-Under acceleration there is no rattle until roughly 3000 rpm. Heavy acceleration there is none.

-It happens in neutral with throttle at about 2000 (As seen in videos.)

-It will also happen once you release the throttle, think the few moments between a gear change.

-It is NOT heard at idle or cruising down the highway.

What I already checked is a visual during valve cover reseal which showed no obvious damage. I also checked compression, 150 psi on all 4. It is not burning oil and there is no CEL.

This video is it in neutral with A/C compressor connected. I am getting it close to 2000 rpm and you can hear the rattle slightly but once the compressor clicks on it gets much worse.

LINK: https://youtu.be/dY3MDowOBPs

And this one is without the compressor going, it is much harder to get a steady noise.

LINK:https://youtu.be/gr6JcziFdRI

Thanks for any and all help. More videos and pictures can be had if you need them.

Dirtman · Dec 10, 2018

Neither of your videos worked but first, 2.3 duratecs are noisy and rattle even when working perfect.

Second, I can't remeber if they ditched the intake manifold runner control system before or after 2004 but it was ditched in later models because it was absolutely horrible and notorious for falling apart. When the control and rod wear out the runner flaps shake and make a horrible rattling/tapping sound. Then eventually they break off and send shards of plastic through your intake.

I would first verify if your engine has the runner control system, if it does that's definitely the first thing I would be looking at.

Pez · Dec 10, 2018

Yeah I am crap at embeding videos apparently. Here is a link to the video with the compressor clicking on. https://youtu.be/dY3MDowOBPs

I will do my search for this runner control system and report back

Pez · Dec 10, 2018

Looks like the IMRC is specific to the 2003? Checked the location I found for it online(under intake towards the rear) and I do not have one.

Dirtman · Dec 10, 2018

Ok that worked, the compressor definitely seems to have an effect but I feel thats probably just due to the extra load on the engine.

Check on that runner system but if you do not have it...

Here's what I would do. Let the engine cool completely and remove the belt. Start the engine (don't run it for more than 1-2 minutes) and see it the noise is gone. If so the noise is from one of the belt driven components. If it's still there youve at least ruled out several suspects. But it sounds like a pulley or bearing on one of the belt components to me.

Pez · Dec 10, 2018

Pulled off the accessory belt and the noise is considerably better. Sounds worse in this video actually.

https://youtu.be/RY82eZvj5PE

I will try the same thing tomorrow after I get back from work with a warm engine to see if its the same.

Dirtman · Dec 10, 2018

The noise still being there but getting better with the belt off says 2 things, it's not related to any of the belt driven accessories but it is effected by engine load. like I said earlier duratecs are noisy but I can definitely hear something that's not typical duratec clatter.

This one has me stumped, I suggest doing the ole screw driver stethoscope trick to see if you can pinpoint a specific point the noise is coming from. 164,000 miles isn't really alot for a duratec which makes it hard for me to imagine a internal issue like timing chain, bearing, or valvetrain issue unless the truck was severely neglected.

pjtoledo · Dec 10, 2018

do you have the round thing with a top connector and vacuum line at the rear of the intake?

Pez · Dec 10, 2018

I do not have any of that. Thankfully?

Dirtman, I'll start checking. I have stethoscope at work and will report back during lunch.

My next thought with good compression is either bottom end or timing chain issues. I'm hoping for the latter... To check bottom end I would normal connect a manual gauge and check oil pressure for being erratic. Is there a good place to tie into the oil system to check other than going where the oil pressure sensor mounts?

EDIT: Check youtube and is the oil pressure sensor mounted on the oil filter housing on these Duratec's? Thought they where on the head like the Lima's

pjtoledo · Dec 10, 2018

that's the flapper control stuff, you are lucky not to have them. just verifying what you have.

I have a 2005 with the same engine. it has 347,500 miles and never made the sound you have.
do you have a vacuum gauge? if the noise is only at a certain pressure, or fluctuates that would help us.

Pez · Dec 11, 2018

I do have a vacuum gauge but will have to coble together some adapters so will report back on that.

Pulled the oil pressure sensor and installed my Matco gauge. With engine warm I had about 35 psi at idle and around 2000 rpm I had 65 psi. With the rattle at its loudest the oil pressure did not fluctuate or seem responsive to the noise at all.

I apparently lost my stethoscope so a long screw driver couldn’t help me pin down the sound at all. I will try again when I have more than a 30 minute lunch.

Definitely concerned about lack of maintenance being the root of my issues. The spark plugs where submerged in oil due to bad valve cover gasket. Plus various other leaks

Dirtman · Dec 11, 2018

The biggest cause of leaks on the duratecs is the PCV valves. They are a pain in the ass to change... So no one ever does. Once the pcv valve clogs pressure builds and leaks start. combine that with a poor oil change record and its easy to get a sludge filled engine and wear parts.

Let us know when you get the vac guage rigged. Lots of info can be had from such a dinky tool.

Since you said you were going to do the valve cover anyway, good opportunity to see the oil service history and how bad overall the engine is. If its loaded with sludge theres a good chance the chain & tensioner will need service.

Pez · Dec 11, 2018

Ok my vacuum gauge will not work. I will see if I can borrow one soon.

Found my stethoscope, checked over engine and the best I can pinpoint is under the valve cover. It is most noticeable around #2 and 3.

I definitely have something up with my PCV as there is positive crankcase pressure so after I repair the rattle that will come next.

Tried something for shits and giggles.. 2000 rpm with belt on, rattle is there. Disconnected #1 spark plug wire, still noise so reconnected #1. Disconnected #2, NO noise. I got maybe a very very slight noise rapping the throttle but it was what could be called normal? Reconnected #2 and Disconnected #3. Still had noise and same "test" for #4. Again had noise.

So with fire removed from #2 my rattle goes away. Burnt valve?

Ran through a compression test again with engine hot and got 145psi on all 4.

pjtoledo · Dec 11, 2018

if you happen to pull the valve cover again be sure to measure the valve lash.
these have mechanical "cam followers" and need to be in spec. adjusting the lash is done by replacing the cam follower with one of the needed thickness, the camshaft must be removed to do that.

you mentioned positive crankcase pressure? that's interesting because if the PCV is clogged there is still a line going from the intake tube to the valve cover that could relieve the pressure. its before the throttle so there won't be any/much vacuum there.

a random idea, run it with the oil cap off. that will relieve any crankcase pressure. it will get some splatter, loosely cover it with a rag. can also stick a hose in to listen.

Dirtman · Dec 11, 2018

The line on the valve cover is for metered fresh air entering the crankcase, in the event of a pcv failure it will reverse flow and blow dirty crakcase air out but I do not think it can flow enough to be effective. Its not ment to be a failsafe. I did my pcv valve for the first time at 60,000 miles (only 50k overdue... Shut up). It was pretty much clogged shut and my throttle body was full of crap from the reverse flow of the valve cover vent. I also developed a timing cover leak that stopped when I replaced the pcv valve...

I actually hate the duratec pcv system so much I spent about $150 bucks on a Volkswagen GDI oil catch can, a ton of 5/8" silicone hose and an inline pcv valve. next time I have to tear the the tire and inner fender off to change the factory pcv valve I plan to put a straight nipple on the oil separator attached to the block, throw out the oem plastic tubing and install the catch can/pcv valve up near the battery. At least then I can change the pcv valve in seconds and drain the catch can at will. I plan to keep my truck forever so it will save me countless hours of bullcrap and maybe keep the intake a tiny bit cleaner.

Whats that Rattle?

New Member

Former Middleweight Moss Fighting Champion

New Member

New Member

Former Middleweight Moss Fighting Champion

New Member

Former Middleweight Moss Fighting Champion

Well-Known Member

New Member

Well-Known Member

New Member

Former Middleweight Moss Fighting Champion

New Member

Well-Known Member

Former Middleweight Moss Fighting Champion

Sponsored Ad

Sponsored Ad

Member & Vendor Upgrades

Truck of The Month

Recently Featured

Follow TRS On Instagram

TRS Events

25th Anniversary Sponsors

Check Out The TRS Store

Sponsored Ad

Sponsored Ad

Sponsored Ad

Amazon Deals