dancing temperature guage

[Danimal86]

Well, i was driving home from work today....driving about 80mph, and i noticed my temp guage was between the A and L of NORMAL, i quickly slowed down, cranked on the heater full blast, hope'n it wouldn't go any higher....it droped back down to about the O....i know that these temperature guages, are innacurate, but this is the first time that it has done this. My thermostat is only about 3 months old...i checked the radiator resevior and there was plenty of fluid in it. Any help would be appreciated!

 

[boggs1227]

burp or flush it

 

[Danimal86]

burp?

 

[Blacksheep Josh]

Get any air that may be in the system out.

http://www.ehow.com/how_7369_burp-cars-cooling.html

I did this on a second generation, after I had replaced a lower radiator hose, and it was kinda weird. As the engine was burping itself, and getting the air out, it'd suck the water/antifreeze from the reservoir into it, and I'd turn it off, refill what I could, and kept doing it until I felt it was good.

Just make sure if you do it with the radiator cap off, you water the temperature gauge. If you do it in small increments you should be fine, if the engien gets to hot just let it cool down and repeat.

 

[Danimal86]

just tried burping it, and i haven't driven it around yet, but the fluid level in the radiator didn't go down at all, and there was plenty of fluid in the radiator....what next?

 

[boggs1227]

the burping method i have used in the past is to take the cap off cold with engine off .next squeeze the upper untill you see the level go down slowlly .after several times of this (it will stop going down eventually) then fill the rad back up the top with new coolant ..your basiclly purgeing the air out by forceing coolant into the engine block and not letting the water pump do the work (sometimes the pump will cavitate to much and still have air in the system.every body has there methods but this has worked for me so far .

 

[scrivyscriv]

Danimal,

Go get you one of those $5 Prestone radiator flush kits and give your radiator an enema if you haven't flushed it lately.

Mine was doing the same thing, even after I replaced the thermostat, and backflushing it after 2+ years of NOT flushing it immediately fixed the problem.

 

[Danimal86]

well, i dont know if this was a coincidence, but when i was having problems with my temperature gauge, i was at about a quarter (or less) tank of gas....i went and filled up before i hit the freeway, and the problem stopped....is it possible that the fuel level could have an effect on my engine temperature?

 

[gsmaclean]

Could also be a sticking/failing thermostat.

 

[boggs1227]

i would say no way .... not unless the added weight of fuel made your truck more heavy and put more of a load on the engine to haul that extra weight but if you were only a 1/4 down in the tank i just don't see how the little extra could have a effect on the guage reading normally .

do what scrivyscriv said and bo buy one of those prestone flush adapter kits and flush the system .when i installed mine it's on the heater hose (the one that runs right next to the air box ...best location imho...has enough angle for connecting the water hose and is not next to the firewall and other electronics).

the arrow is where i installed mine .

edit : could alos be the stat as well ...when was the last time that was changed ?

 

[mikeinri]

Wow, is that a clean engine bay! Definitley obvious you don't live in snow country!

BTW, I see you have embraced the same technology as I did for the MAF electrical connector.

Sorry for the hijack, back on topic...

If burping doesn't fix it, the sender could be bad, or the t-stat could be bad, or not installed correctly (weep hole up I believe). Note, there are two separate temperature senders, one for the gauge, and one for the computer.

Hope this helps.

Mike

 

[Danimal86]

is it possible that the gas i had in there was causing my car to run hotter?
I'll probably go pickup one of those flush kits, but i recently (about 3 months ago) had a horrible coolant leak...turned out i needed a new intake manifold....while it was in the shop, i had them put in a new thermostat, and a fresh batch of coolant....

 

[mikeinri]

It is uncommon, but not unheard of, for new t-stats to be bad out of the box. Since you didn't replace it yourself, there's also no guarantee that they put the right one in. For the 10 bucks and 30 minutes of work, I'd replace it to eliminate the possibility.

Mike

 

[boggs1227]

Wow, is that a clean engine bay! Definitley obvious you don't live in snow country!

BTW, I see you have embraced the same technology as I did for the MAF electrical connector.

Sorry for the hijack, back on topic...

If burping doesn't fix it, the sender could be bad, or the t-stat could be bad, or not installed correctly (weep hole up I believe). Note, there are two separate temperature senders, one for the gauge, and one for the computer.

Hope this helps.

Mike

: you like that !? funny i found out why it would not stay connected ( it would click like it was on there but really it was'nt) i was cleaning the iac and the maf and noticed that the old weather boot from the old maf was still on the wire harness ( i thought it was suppose to be there but after looking at the new maf it already had one ......big duh ! now no more tie wraps !!! lol

back to the topic .....let me ask why the intake manifold was replaced ?
cracked ??

 

[Danimal86]

it wasn't cracked, but apparently the gasket was shot and it eroded part of the manifold, and sent coolant leaking out...

 

[scrivyscriv]

is it possible that the gas i had in there was causing my car to run hotter?
I'll probably go pickup one of those flush kits, but i recently (about 3 months ago) had a horrible coolant leak...turned out i needed a new intake manifold....while it was in the shop, i had them put in a new thermostat, and a fresh batch of coolant....

I'm not gonna say the gas thing can't happen..... But very unlikely.

 

[Danimal86]

well, i thought that it had stoped, but driving home after school today it did it again, i noticed that my check engine light had gone on (and then flicked off), looked at my temp guage, and it was at the L of NORMAL.....i cranked on the heater, and took my foot off the gas.....the temp went down, and continued to fluctuate....it seems to only happen when im on the friday.....could this be just a bad thermostat?

 

[scrivyscriv]

One other thing not mentioned yet... Check your water pump.
Run your engine to normal temp, then squeeze the upper rad hose. You should feel it build up pressure from the water pump running, and if you don't, you need another water pump.

Also, unless you can 2x check with the shop or person who fixed the coolant leak previously, I would assume they did not backflush your radiator. I don't believe that's normally done as part of that kind of job unless you specifically ask them to.

- edit -

It could be the thermostat, yes.