2004 explorer 4.0 v6 engine problems

[ziob]

hello everyone,
have a 04 explorer with 4.0 v6 engine that was losing coolant and had some of the milky stuff in the oil cap that would lean towards a head gasket. All mechanic performed head gasket leak and pressure tests came back negative and no smell out of the tale pipe of it burning off...no visible leaks. Anyway got bad to the point couldn't drive it so we put in engine block sealer which has stopped the leak. However now on startup especially when its cold the engine will rattle / tick and it'll take a good 20 or more seconds for the oil pressure light to come on sometimes more the colder it gets. After that can drive it around doesn't overheat only makes a slight noise when you give it gas almsot like its sucking for air. Any one ever have this problem or have any ideas on what it could be?

oil pump or pressure sensor gummed up with the sealant? Outside of that everything is fine. probably will run it until it blows but curious on what it could be if not headgasket or crack in head.

 

[MrBean]

I had the same issue not too long ago, a former ford dealer mechanic told me that milky cap is normal...Anchorage is a small city and i do alot of short trips in town and he told me its normal, just keep up with the 3000 miles or less oil change...i changed my oil, put seafoam into the oil and ran it for a week then drained the oil again...had no issue ever again...good luck and hopefully you wont loose your engine

 

[Exproblems]

hello everyone,
have a 04 explorer with 4.0 v6 engine that was losing coolant and had some of the milky stuff in the oil cap that would lean towards a head gasket. All mechanic performed head gasket leak and pressure tests came back negative and no smell out of the tale pipe of it burning off...no visible leaks. Anyway got bad to the point couldn't drive it so we put in engine block sealer which has stopped the leak. .

Milky crap under the oil fill cap is normal, has to do with "condensation" if I remember what I read a while ago correctly. I think a switch to full synthetic oil will keep that white milky stuff under the oil fill cap from forming. I didn't see any milky build under my oil cap on my previous motor using full synthetic oil. Milky colored oil in the crankcase on the end of the dipstick is bad news, coolant in oil. If you had a head gasket leak test done by a mechanic and no problems found by the mechanic, can't understand why you dumped a bottle head gasket leak sealer into the motor. :scratch: Should have spent more time looking for the source of your coolant leak.

 

[ziob]

we did nobody could figure it out mechanic friends etc only way was to tear into the motor and when you do that with these there is the inevitable timing chain replacement....basically it would cost way more than what the car is worth just to find out the problem which could be a shot engine on its way out so i opted to dump the gunk and run it until the leak starts again or the engine is a goner. Anyway never had this chatter when starting the engine and didn't have the oil pressure guage not work until after i dumped the stuff. Ran great no leaks for a few weeks driving around town then the chatter started when you first start it....as the engine heats up it lessons and when the engine heats up oil pressure guage finally goes up....chatter is pretty bad in the cold. no milk on the dipstick and all tests we negative no idea what the problem is.....maybe it developed the timing chain problem alongside of the other issues it had?

 

[Exproblems]

we did nobody could figure it out mechanic friends etc only way was to tear into the motor and when you do that with these there is the inevitable timing chain replacement....basically it would cost way more than what the car is worth just to find out the problem which could be a shot engine on its way out so i opted to dump the gunk and run it until the leak starts again or the engine is a goner. Anyway never had this chatter when starting the engine and didn't have the oil pressure guage not work until after i dumped the stuff. Ran great no leaks for a few weeks driving around town then the chatter started when you first start it....as the engine heats up it lessons and when the engine heats up oil pressure guage finally goes up....chatter is pretty bad in the cold. no milk on the dipstick and all tests we negative no idea what the problem is.....maybe it developed the timing chain problem alongside of the other issues it had?

If anything, I would do an oil and filter change soon and see if that clears up the chattering and oil pressure gauge issues. It's a cheap test and remedy if it works.

 

[ziob]

could try, oil change was already recent i doubt that would fix the issue. cheap but probably a waste of 25 bucks? ever heard of the timing chain problems these engines have they almost slip a tooth or something and they chatter / make noise

 

[ponkotsu]

Could also be bad PCV system causing moisture in the oil. Replace the valve and check all the vacuum lines. Another good test for blown head gasket is to put the tailpipe sniffer in the overflow bottle and check for hydrocarbons. I would definitely change the oil if you think it's contaminated or it's been more than 6 months. You might try a slightly heavier oil and see if that helps the oil pressure situation.

You said takes 20 seconds for oil light to come ON? Did you mean turn off? No oil pressure for the first 20 seconds is really bad.

 

[ziob]

oil pressure gauge on right side dash takes that long to come on in the cold all while the engine is chattering but the needle will finally come up and as the engine heats up the chatter lessons but is still there when you give it gas faintly. sniffer test done, pressure tests on cylinders nothing came back positive for bad head gasket. like i said only way to know the problem after all the tests was to tear into the engine at an end cost of thousands because you have to do the timing chains once you do that they are in the way.

 

[ponkotsu]

You've definitely got an oil flow issue. I'm not familiar with that engine so can't give you specific advise other than to say you need to address the oil flow or be prepared to replace the engine soon. Could be just a bad filter with no check valve so the filter needs to get refilled each time you start it. I'd change the oil out with full syn and use a K&N oil filter. It will cost you $40 but it's a lot cheaper than a new engine. If that doesn't fix it then you are probably looking at major engine work regardless.

Going back to the root problem, the milkiness under the cap. That is normal to a small extent, but I assume your mechanic knew a good one from a bad one. Could be that it really did have a leak into the crankcase and your oil pickup screen is now clogged with slime.

 

[Exproblems]

could try, oil change was already recent i doubt that would fix the issue. cheap but probably a waste of 25 bucks? ever heard of the timing chain problems these engines have they almost slip a tooth or something and they chatter / make noise

I would change the oil and filter anyhow, since it has that engine stop leak stuff in your current oil and your problems started after dumping stop leak into your current oil. Your problems seem to be related to the stop leak product, so get rid of it and see what happens. Yes, I know all too well about the lousy timing chains and tensioners in these 4.0L motors. The rear timing chain tensioner gave out in my motor back in Late August 2013 during the first startup of the day, causing the timing chain to "slip out of time". That motor was replaced by a new, remanufactured 4.0L engine I currently have. Prior to my timing chain tensioner crapping out, I didn't have the noisy chattering other people have described in here. Mine gave out right on engine startup.

 

[ziob]

stop leak was dumped into the antifeeze coolant and ever since the reservoir has held strong no leaks. I can change the oil look for goop in it but there is nothing on the dipstick. Maybe the chatter and the previous leak are just two seperate issues at the same time (timing chain slipped and now chatters) and then the stop leak stuff clogged up my oil pressure sensor. Really the car needs a reman engine like you did i'm just trying to determine the issues if i sell it and get out from the money pit....not worth dropping a new engine in it if i don't do it myself.

 

[Exproblems]

stop leak was dumped into the antifeeze coolant and ever since the reservoir has held strong no leaks. I can change the oil look for goop in it but there is nothing on the dipstick. Maybe the chatter and the previous leak are just two seperate issues at the same time (timing chain slipped and now chatters) and then the stop leak stuff clogged up my oil pressure sensor. Really the car needs a reman engine like you did i'm just trying to determine the issues if i sell it and get out from the money pit....not worth dropping a new engine in it if i don't do it myself.

I think I understand you now, you dumped "radiator stop leak" into your coolant thru the reservoir? The "engine block sealer" you spoke of in your OP is a completely different stop leak product. You also mentioned in the OP that you "thought the oil pump pressure sensor may have gotten gummed up by the sealant". This is why I thought you dumped some kind of engine block sealer into your oil crankcase. If you didn't dump any kind of stop leak into your oil crankcase then forget what I said about changing the oil because of that. If you are having some kind of oil pressure supply problem to the engine or it's parts, it isn't because your cooling system is leaking coolant, unless the coolant is leaking into your oil crankcase and contaminating the oil. If the oil in the crankcase is clean and free of coolant contamination, then I wouldn't be concerned with the condition of the oil. Did you ever over heat the engine from the loss of coolant thru the leak? That can blow a head gasket, an over heating condition.

 

[ziob]

never overheated it and all the tests you do from pressure to reservoir fumes etc all came back negative or no obvious signs of that head gasket leak....whatever leak there was was clogged up with the sealant but now we have that old rattle in the engine and the oil pressure deal this started relatively soon after the sealant clogged up the antifreeze leak. crank case oil isn't contaminated at all nice and clean. Its been a mystery the engine is bound to crap out soon with the noise its making but once it warms up it actually runs pretty smooth.

 

[ziob]

started it this morning very cold out oil pressure gauge doesn't go up at all has light rattling and the sound almost of like a fuel pump engine must be on its way out probably time to junk it.

 

[diff]

Makes me wonder if oil pickup screen is clogged with bits of plastic from the timing chain guides. We are trying to get familiar with ours so I have done a lot of reading but more to go. Not sure whats involved to pull the pan and or remove oil pressure sensor to see if gunked and test it or replace it to get a better sense of the oil pressure on start up and running. probably awkward to hook in a reliable non electronic guage but I might be tempted to do that first. the more I read the more I worry about this rig.

 

[ziob]

these years explorers were absolute garbage especially the transmissions they can go anytime every person that i know thats had one has had the tranny go in it. I'm gonna pop my oil pressure sensor out to see if its gummed up but i doubt it think the engine is just got all sorts of issues and is about to pop.

 

[ziob]

sensor seemed clean but it could be bad.....has that rattle on cold start up on the drivers side right by the oil pressure sensor somewhere....gets less and less as engine warms up but is still there....now when you give it a good throttle oil pressure gauauge on dash will go to no pressure and check gauge light comes on.....if you let it back down light will go off and oil pressure gauge will go back to normal? sound like a bad sensor?

 

[2000StreetRod]

oil pressure switch

If your engine is like my 2000 there is no oil pressure sensor. There is only a switch that closes when the oil pressure exceeds about 5 psi. The oil pressure "gauge" on the instrument panel is merely a glorified idiot light. The red arrow in the photo below identifies where the switch is located.

In the photo below the item on the right is an example of an oil pressure sensor and the oil pressure switch is at the bottom.

It is common for the switch to fail after many years of service. Unfortunately, the switch is difficult to access and there is no other port on the engine to measure oil pressure with a mechanical gauge. I found access was best while working under the vehicle and reaching up to the switch.

 

[ziob]

this one is not as bad to get at i took it out easily and cleaned it and checked connection this explorer seems like a case of everything going bad at once. I got this sensor going bad or was clogged so from time to time the idiot gauge on the dash would fluctuate go off...not come on............then i got the rattle under the hood which is probably the timing chain guide broken or slipped (apparently common problem) and then there was the leak which was fixed with a little enging block sealer hasn't leaked for months since. thanks for the input though i'm just gonna bail out of this truck and never get these year models again to many issues.....such a clean truck though what a shame.