Great. LS wants to play games. Need an opinion here..

[lincolnlogs]

2nd time this has happened. First time was 2 months ago and exactly the same, but never happened again until now.

Start car in morning.
drive car 7 miles to school.
soon as i get to school, **ding ding** check engine temp. (its pegged) along with "reduced engine power" and the unique noise that makes.
freaking out, i whip into the parking lot quick and kill it. the fans were running full blast, as i popped the hood. Nothing smells hot, nothing feels extremely hot, no coolant loss, no stiff hoses, no sign of coolant smell.

wait 5 mins, restart, bam. no CEL.

normal temperature. and drove it 68 more miles without it happening again.
2 months later, same thing happened, same scenario.

except this time i let it run for a second (which it would stumble at idle, and almost stall out) and finally got: P1285 and P1299 Codes.

#1 I know that coolant wise, my car was not overheating.
#2 i know the gauge is tied along with both coolant and hydraulic temps.
#3 hydraulic lines didn't seem ridiculously hot, nor did anything really.

is my car actually overheating? is it a bad sensor? anyone seen this before?
why is it so intermittent? i started and drove it 4 times after it happened today and didn't have a problem....

of course, once i get it all tricked out it wants to play this business.

:bsflag::bsflag::soapbox::soapbox:


bigrig?

 

[lincolnlogs]

and also, first person that says i need a hydraulic pump, is no longer going to be my friend.

 

[RigsLS]

What? I didn't do nuthin!

 

[stugots]

Sounds like the typical cooling system problems. You probably will have problems with the fan sooner or later.

 

[lincolnlogs]

What? I didn't do nuthin!

either did i?!

i need a hand here, before i start tearing into things...
lol

it says check engine temp.

i did. nothing was even hot. (at least what i could touch and get at)

do these sensors go bad for these hydraulic systems?

also, the fan works by the hydraulic system, if im not mistaken. fan works on both high, and low. AC on, Fan on. and "check engine temp" on, fan on high.


i thought maybe it could be a thermostat, because upper hoses were warm, lower one wasnt. but it seemed like the plastic line before it hit rubber on the lower line was warm. (which is after the thermostat) so im lost.

 

[lincolnlogs]

i have had an overheating engine before..

hearing coolant boiling, stiff hoses, coolant smell, overflow bottle full, etc.

i had none of it.

 

[stugots]

Cracks in the plastic parts let in air. The air causes hot pockets in the engine which tell the computer it's overheating. I'm not sure what those codes are, I'm sure joe does.

 

[lincolnlogs]

i'll be patient and wait for his reply.

in the meantime, anyone know why my engine load would be at 31% at idle? doesn't seem right to me.

 

[stugots]

That's about what mine is.

 

[RigsLS]

Just a pre-note here: There are far greater guys on here that know much more than myself, I am by no means the LS wonder around here.


Cooling system needs several things, proper coolant mixture and level, sufficient pressure, adequate coolant flow and sufficient airflow.


Seems it's a temperature gauge problem rather than an actual overheating condition.

Is the coolant still good in color and it's mixture is correct within limits?

- Maximum coolant concentration is 60/40.
- Minimum coolant concentration is 40/60.


Might be a failing cylinder head temperature sensor. Even a bad ground somewhere.

Your P1299 code indicated you should possibly focus on cylinder temperature sensor, it appears to detect an Engine Overheat condition whenever it is happening.
P1285 code indicates cylinder head over temperature condition sensed by the cylinder head temperature sensor.

Like someone already mentioned there obviously can't be any leaks in the system as it needs pressure throughout.
You don't see anything at all, any white dried residue. degas bottle level is still the same level when cold ?

 

[RigsLS]

Just for sake of argument possibly check your wires/connector to the cylinder head temperature (CHT) sensor.

- - - - -

Cylinder Head Temperature (CHT) Sensor —3.9L

Removal and Installation

- Disconnect the cylinder head temperature (CHT) sensor electrical connector.



- Remove and discard the CHT sensor.



- CAUTION: The tip of the CHT sensor must contact the cylinder head at the bottom of the hole. When removed, it will be slightly crushed. This is a normal condition.

-NOTE: 3.9L CHT sensors are not to be reused. Always install a new sensor.



Item 4: p/n 6049 - Cylinder head, RH
Item 5: p/n 6G004 - Cylinder head temperature sensor, RH





^ B135 = Cylinder head temperature sensor


Might be on it's way out or just corroded connection.
Intermittent issues are a bitch to troubleshoot aren't they ?


Either that or your thermostat is sticking but you said it was not hot before and after the stat, so .... airlock boiling at cylinder but I doubt it.

 

[rsimmons1]

Thermostat stuck shut? I had the same issue a week or two ago and that's what the shop told me.

 

[joegr]

Your LS only has one fan.
Your temperature monitoring is not tied into the hydraulics in any way.

You are starting to have they typical cooling system issues. Replace all the plastic, the thermostat, the degas bottle, and flush the system.

The way the temperature gauge works is that it doesn't go above the mid point until it actually is already overheating. It's possible to go above this threshold, stop for a few minutes, and then be below the threshold when you restart.

Use your scan tool to monitor the temperature sensors.

 

[adamfysher]

Degas bottle?

I had that exact same issue. I did not see any leakage, but my degas bottle had a small crack allowing air into the system. I replaced the degas bottle and bled out the cooling system. I have a 2000 with the 3.9. The bleed valve is to the left of degas bottle (aka coolant overflow reservoir).

 

[RigsLS]

keep in mind it's not a constant problem for him, only happened twice. seems normal any other time with no real overheat conditions present at the time.

I'm usually wrong before I'm right but what about clearing the codes,
disconnecting the CHT sensor and see if it reproduces the symptom immediately again.

might be worth a shot.

ECM records temperature trends via the engine temp sensor and when it reads a fluctuation different than the trends it will produce that code.

 

[Telco]

My degas was also cracked. I could hear (surprisingly, as I'm deaf as a stump) a very low volume bubbling noise from behind the dash. When I replaced parts I found the inside of the thermostat housing cracked. However, I did NOT have overheat problems. Temp was rock steady, just a hair above centerline on the guage, at all times once the car came up to operating temp. That means nothing though, as it depends on how the thermostat pops when the housing fails. I could see it jamming open, closed or partially, as mine apparently did. The main difference before/after is that I no longer hear the bubbling, and the car gets up to temp a LOT faster than it used to. Used to take about 6 miles to reach operating temp, now it takes about 2 miles.

 

[lincolnlogs]

Your LS only has one fan.
Your temperature monitoring is not tied into the hydraulics in any way.

You are starting to have they typical cooling system issues. Replace all the plastic, the thermostat, the degas bottle, and flush the system.

The way the temperature gauge works is that it doesn't go above the mid point until it actually is already overheating. It's possible to go above this threshold, stop for a few minutes, and then be below the threshold when you restart.

Use your scan tool to monitor the temperature sensors.

Joe - i agree with what you, and bigrig are saying. however, this problem WILL ONLY HAPPEN from a cold start(6+ hours of sitting) its never happened while i was driving. and not only is it intermittant, but as soon as i get out, shut it off, squeeze a few hoses, and mess around, (less than 5 mins) it's back down to normal temp. -if it was actually THAT hot it would take a while to cool down. especially with the engine off. no?

coolant level is slightly higher (1/2in) at running temp. but only varies that 1/2in.

i'd believe that the thermostat is getting stuck, but maybe there is more than that. i thought maybe its possible its not building enough pressure to pop it open? these should at least be 10 psi at least at the cap right?

i took it out this afternoon from a cold start, drove it a fairly hard 6.5 miles, and let it idle for 3 mins. soon as i shut it off, i loosened the cap on the reservoir to check the pressure. heard maybe a small hiss. id guess maybe 2psi.

seems to me there should be more than this, no?

and as far as dried white coolant, this is all i could find. after my drive, it was still dry as a bone.

ill check the scan tool tomorrow for readings.. but as of now i believe i might have a simply plugged up thermostat or a few cracks not allowing me to build sufficient pressure. or the possible bad sensor because its so randomly happening. although you'd think if i had a few cracks id have some leaking coolant too?

weird part is, each time its happened, after i squeeezed a few hoses, and flipped the key a few times i drove it for the rest of the day with AC on and in the heat. no problemo.

thoughts?

 

[lincolnlogs]

My degas was also cracked. I could hear (surprisingly, as I'm deaf as a stump) a very low volume bubbling noise from behind the dash. When I replaced parts I found the inside of the thermostat housing cracked. However, I did NOT have overheat problems. Temp was rock steady, just a hair above centerline on the guage, at all times once the car came up to operating temp. That means nothing though, as it depends on how the thermostat pops when the housing fails. I could see it jamming open, closed or partially, as mine apparently did. The main difference before/after is that I no longer hear the bubbling, and the car gets up to temp a LOT faster than it used to. Used to take about 6 miles to reach operating temp, now it takes about 2 miles.

also funny, that i believe i heard the same thing. i'll check tomorrow.

 

[lincolnlogs]

done some thinking. its simple. im not building pressure.

trying a new cap first, becuase this one doesnt seem to seal right. if i still dont gain pressure, ill be replacing all the plastic lines and bottle.

keep you posted! thanks joe, what you said makes sense. just because the temp dropped back down instantly doesnt mean that it cooled down that quickly. simply means the system reset it, and shutting it off cleared the air pocket out.

 

[Telco]

Bigrig had a pic of his degas bottle, the cracks were so much like mine he may as well have posted a pic of my old bottle. Yes, you have a leak, and since you have to bust the system open anyway go ahead and replace all the hard plastic and the hoses. It's not hard to do, just a lot of "what the hell were they thinking" things. Expect to remove the upper manifold plenum to get that one plastic neck off, for example. They could have used 1/2 inch shorter bolts (which mine now has) or moved the bolts 1/2 inch closer to the front of the engine and the intake wouldn't have to come off. I didn't even have a manual and the job went like I'd been doing it for years except that someone who does it for years knows how many gaskets they need to have on hand.

 

[lincolnlogs]

any place i can get the plastic parts

 

[1LoudLS]

i got most of mine through rock auto, the ones i couldn't get from there i got from fordpartsgiant.com

 

[Telco]

Got mine from Rock Auto and Silver State Ford .com.

 

[RigsLS]

and on top of that my Degas bottle, which had a total of three cracks in it, only on the last occasion was actually leaking behind the front wheel well, topped it up twice over the span of two months or so, ... never overheated once! No heat was Dccv and Aux pump.

but despite air in system, low pressure, multiple cracks in bottle ... never once overheated. Rather odd.

I see I was way off on the CHT sensor, it was leading me that way because of how it was described that it didn't
actually appear to have actual overheat condition and would only do it twice in 2 months.

wrong again ... what else is new.

 

[purevilpleasure]

I'm just curious...does this site have a signature height max? When I see signatures that take a full page it's getting a bit over kill.