washed the engine bay a bit sat....now heat blows cold?

[jasonroman]

make any sense?
sat after work, i decided to try and clean up the engine a little bit and change my valve cover gaskets.
so i sprayed a little simple green and then water to try and get some of grime and grease off.
then i hit it with a little compressed air. changed valve cover gaskets.
then monday was taking my son to school and noticed that cold air was blowing.
why would this happen?
prior to wash and gaskets, the heat worked as it should.??

[BlackTopMotors]

It could just be a coincidence. Do you have a valve that lets heated water through the heater core?

[85Bowtie]

That's usually sign of a bad head gasket or air in the system.

[jasonroman]

Originally Posted by 85Bowtie

That's usually sign of a bad head gasket or air in the system.

a bad head gasket??
would this have been something that was going bad?
would this have happend in my cleaning of engine and changing valve cover gaskets??

how do i check and how hard if its gone bad?

thanks again for any help and advice

[motornut]

no coolant leaks?or low
do all the other heater controls work right?
maybe you knocked off the vac feed for the controls?
the valve ,i've had it for rear heaters in burbs with a dual heat/ac core unit(keeps the heat from going threw when the ac is on)
havn't seen it on reg front heat/ac's

[jasonroman]

no leaks that ive noticed.
truck seems to run good. with no probs.
i know rad needs to be changed. just dont have the money now to do it.
sometimes a drop or 2 will come out. but its weird. couple drops, then runs dry... as in no leaks.

as far as if my controls work right.
thought i only had the one to control. from in cab. and they seem to work ok.

no much noise from the 2 lower settings but higher 2 sound and prove it works.

prior to me wetting things down and moving stuff around a bit for access to gaskets. i know it worked.

thanks for the help tho man.

[jasonroman]

Originally Posted by BlackTopMotors

It could just be a coincidence. Do you have a valve that lets heated water through the heater core?

thanks for reply.
not sure if i have the valve your talking about tho

funny thing was later on the same day i posted this....
i drove to work, and put the heat on and it was warm. then later turned cool again.

why would this happen. either be cold, no heat. or sometimes throw hot air?

[bigd65]

I dont know if anybody had suggested it but check the vacuum hose that goes through the firewall by the evaporater ( I think that is what its called )It controls the duct door inside of the cab. If it is not connected it will make the control doors for cool and hot air act all crazy and haywire. I have knock mine of on several trucks and hunted the same problem

[jasonroman]

thanks.
gonna have to try and find what your talking about. good chance that could be it.
moving things around to get gaskets off, and pulling wires to better route them might have led to me knocking this thing off, or loose. now just gotta find it.

[bigd65]

Should be a plastic vacuum line and should run from the passengerside firewall to behind the carb and attach to the carb or the intake.