Hi guys, I just got my first vette and I absolutly love it. It's a 1986 coupe and has the digital climate control . I took my car to the car wash the other day, and washed it all up nice, then went to turn on the heater the next morning because its Texas here, and one second it's 900 degrees and next second its -40, anyway, steam comes out of the vents as the car warms up. Theres a hint of antifreeze smell, but I dont see anything leaking and everything seems fine as far as fluid levels etc. The car has not over heated or anything remotely close, and I've drivin it along way at 122mph. I'm thinking heater core, but I have no clue...can someone help me out and let me know what to check about making the steam stop coming out? I know I need to replace my climate control as some of the buttons arent working, but that'll come soon enough. I'm pretty much a novice at mechanics, but I can hold my own I guess. Thanks for the help!

 

Yup, sure sounds like a leaky heater core !!
It takes 2-3 hours of farting around in an awkward position, but is doable for a novice. Use the advanced search function and search "Fastguy method".
If you are up to the task, I'll post some pics and info from my experience.

 

I would definately appreciate any info you can give me. I kind of figured that was the problem, and I've heard it's a nightmare to replace one, but with some help, anything is doable.

 

Here is a breakdown of what I did, it's been a few years, so I might miss something.
Remove passenger seat
Remove lower dash panel (the one with the courtesy light)
Remove connector to temp door motor
Remove ECM ( held in by two 10mm screws, remove them and slide the ECM down and out of the way. You can disconnect it and remove it entirely)
Disconnect rod from connector at door motor arm.
Remove the door motor
Remove the tubular angle brace
Disconnect small duct-work
Remove all the screws holding plastic cover
Wrestle cover off
Re and re core and put it all back together.


The top 2 screw on cover are a bitch, knowing where they were, would have made it easier.

Here is a few pics of what you'll find.


ECM removed, door motor ready for removal.



Close up of rod connector on motor



Door motor removed, bolt for tubular brace is easily accessed now.



Pic of cover showing where the top 2 screws are located.



Cover off

 

Here is some info on the HVAC system from my FSM. Save it
http://members.shaw.ca/dankai/HVAV'S.pdf
http://members.shaw.ca/dankai/HVAC%20Electrical.pdf

 

Is there any task you can't complete? I mean I did the heater core as well but you have a archive of information.

 

one more question...since I have the digital control, can I replace it with a manual one or is there a ton of stuff involved? I'd rather have the reliability of a manual as opposed to the luxury of the digital one.

 

I would imagine that going from electronic to manual is quite doable, provided you track down all the correct parts.
There is some info in tech tips regarding cleaning the contacts etc in controller. I had some flaky buttons until I went inside and cleaned things up. All has been good since then (5 years)

 

awesome. Thanks so much for the help. I upgraded from an 84 Trans AM and the forums/folks here are much more helpful and definately more kind than those from the TA forums. I appreciate all you do, and I'm proud to be a part of the Corvette Brotherhood.

 

Hey Dan... I don't see the picture with the axe

 

 

I didn't want to scare him away from doing the job himself.

 

LMAO! I've actually seen that before, and although it's intimidating, I think I can manage. I've already been in there looking at it and I am waiting on my heater core to get here. I'm excited, and definately not afraid to get my hands dirty or learn new things. Hopefully I'll be able to post a pic of my old one...I'll figure out something creative

 

great pic!
Jim, be sure to pressure test the new h/c before it goes in the car.

Once it's in the car and plumbed, maybe don't put the cowling/cover back on, drive around for a bit. Look for leaks.

Sometimes new cores are defective right out of the box or they blow within a few miles.

Have fun.

 

Ok, so I found some antifreeze by the thermostat housing and figured I'd change the thermostat and gastket since I had to jack with the heater core, which I still havent started out of being a wuss. LOL! Anyway, I got the thermostat and gasket changed out and let the car heat up. I noticed a puddle of antifreeze by the thermostat housing again, but after i sopped it up with a towel found that its coming from a bolt nearby and not from the thermostat. Can ya'll tell me if I'm screwed? I'm thinking this is bad, but hoping it's not. It looks like its coming from where the torx bolt goes in, but I dont have anything that big to tighten it and not sure what size...let me know if this looks to be a major problem please.

 

If the leak is coming from the bolt, then I believe you have a breech in the lower intake manifold gasket. You may be able to seal the leak at the bolt, but you still don't know how bad the rest of the gasket is.

If you want to know what is involved in removing the intake manifold from an L98, I made a photo doc of my intake swap here:

http://members.***.net/effergyvette/...e_install.html

If you do pull the intake, then you should think about doing "while your in there" items, like servicing the fuel injectors, replacing the EGR valve, and replacing the fuel line "send and "return" O-rings.

 

thanks.

i should do this as i am taking out the factory ecm.

 

Thank you the pictures were very helpful........I swear the 1989 Corvette was designed in Japan.....My Buddy Gabe was finall y able to get the old one out..just discover that the brand new one was crap right out of the box..sooo bypass and autozone can kiss my ***

 

Great instructions with pictures and thanks for sharing. Some things I experienced today while taking on this task with my 88' convert.
1) I did not remove the seat because I did not see the benefit here for I still had to lay accross the door seal with upper body under the dash. (I will understand in the morning why the seat is removed....)
2) There are two screws at the top of the core cover that were challeging. Had to use a couple 6" - 1/4" extensions with swevil and a mirror to get to and see the the screws to remove. To re-install the screws tape the screw to the socket and once tight the tape removes easy.
3) The core has a clip at the top screwed into the plastic. This keeps the core snug in the housing. This was also challeging taking out the core and installing the new one. The clip must be pushed upwards with a flat head screw driver until you wiggle out the core. Lossen the screw that holds the clip in prior to re-installing the core. This allows you some wiggle room when stabbing the core inlet/outlet tubes through the fire wall.
4) Compare the new core to the old and adjust the inlet/outlet tubes prior to installing. Very little room to wiggle the core into place.

Other than what I listed, the pics and steps were a great big help! Not sure of any other way of changing the core. Thanks for the info and hope what I listed will help someone else.....

 

In the interest of updating some info and adding a pic, I'm posting in this thread. I used this thread as my guide -- so it should be a sticky -- if it's not!

I ended up taking apart more than listed here. Because the bolt holding the upper end of the brace (3rd-to-last pic above) wouldn't loosen using an open-end wrench, I had to pull off the carpeted vanity panel. Not fun. (Didn't enjoy it the first time 2yrs ago. Didn't enjoy it again.)

After pulling the carpeted panel AND the ECM housing, I was able to hook a second wrench on the first open-end -- so I could get enough torque to break loose the upper end of the brace.

The two small screws at the top of the heater core were a blast too! (But probably not nearly as hard as they would have been w/o pulling the carpeted vanity panel. (BTW...This is mounted with 4 built-in studs which point up into the dash. I can post a pic if anyone wants.)

Of course, I also took off the dash as evident in the pic below. And, that brings me to my question (and reason for posting.)

In Agent 86's pic above, the ductwork in front still looks attached after removal of the heater core cover. But I don't see how to pull the cover w/o that (gravy-boat-shaped) duct coming off.


The blue line shows how long that duct extends. The red line indicates that I can't pull it to the right. (Before I got the cover loose, it also hit the circular inlet hole on the front.)

So, what's my next move?

Also, are there two screws that hold the left BIG ROUND SEMI_SPHERICAL end together? I can't see up there. (In the 2nd-to-last pic by Agent86, I'm talking about the round end pointing straight left.)

Thanks for any helpl!



BTW...I still can't get the cover out because of the piece going thru the cover -- that's a 90-degree arm off that gravy-boat ductwork-snake. (upper small red-arrow)