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Things to watch out for when swapping a heater core

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  #11  
Old 11-19-2010, 09:58 PM
ocielz's Avatar
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well looks like im into a hell of a work out with The Core. Mine crapped out a while back, but since its now starting to get chilly, looks like im finally gonna have to replace it. ordering from ecstuning.com and then gonna have a field day!!!!
 
  #12  
Old 11-22-2010, 12:07 AM
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Well, got the new, correct switch aaaaaaaand no luck still the same story, all the electronic components come on when the key is turned to "on" but upon turning the key to crank, everything still stays on, so it appears you were right Andrew, something has to be unplugged or not fully connected somewhere. First thing we're going to try tomorrow is pulling out the unloader/bypass relay and check it with an ohm meter to verify that it is in fact functioning, after that, trace the wires from the steering column/ignition switch to the relay and make sure they're all correct as well as check the rest of the wires immediately accessible under the dash and if none of that prevails, we're going to pull the dash all the way back out again to check all of the connections behind there and make sure we didn't miss anything upon reattaching the dash to the firewall the first time.

Biggest gripes about this whole thing? Aside from not having my car, I really miss being able to listen to my iPod while driving as well as the fact that its been dumping snow here the last couple days and I can't go engage in any hooliganry in it
 
  #13  
Old 11-22-2010, 12:15 AM
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Originally Posted by A4Cragman
Well, got the new, correct switch aaaaaaaand no luck still the same story, all the electronic components come on when the key is turned to "on" but upon turning the key to crank, everything still stays on, so it appears you were right Andrew, something has to be unplugged or not fully connected somewhere. First thing we're going to try tomorrow is pulling out the unloader/bypass relay and check it with an ohm meter to verify that it is in fact functioning, after that, trace the wires from the steering column/ignition switch to the relay and make sure they're all correct as well as check the rest of the wires immediately accessible under the dash and if none of that prevails, we're going to pull the dash all the way back out again to check all of the connections behind there and make sure we didn't miss anything upon reattaching the dash to the firewall the first time.

Biggest gripes about this whole thing? Aside from not having my car, I really miss being able to listen to my iPod while driving as well as the fact that its been dumping snow here the last couple days and I can't go engage in any hooliganry in it

i figured so because the key switch being faulty is unlikly a slim change of it being bad, whatever is unplug is most likely somthing you overlocked im sure its no big deal just take apart the lease amount of the console and search for that loose or unpluged wire.
 

Last edited by Andrew149; 11-22-2010 at 12:18 AM.
  #14  
Old 11-22-2010, 12:34 AM
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Yea, hopefully its something obvious and not a single wire in an entire harness that has come unseated causing everything else in the harness to work properly except for that one component. I see your point about it being a slim chance that it was the switch, but in light of TheDevil's recent coincidental ignition switch failure when he changed his fuel pump as well as the old switch being physically cracked when we pulled it out to put in the new one and the fact that before the heater core job I could start the car some days without the electronics shutting off and other days starting it and they would shut off, the signs seemed highly in favor of it being the switch, much to my dismay that it wasn't.

But yea, its gotta be an unplugged wire now, there's no conceivable reason that any other component of the crank system would just randomly decide to stop working so we're going to scrutinize every last connection under there and hope something jumps out at us fairly quickly that will take care of it.
 
  #15  
Old 11-22-2010, 01:08 AM
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yep, like you said there no clicking on the starter right? so theres no power going to it so whatever wire that is loose/unpluged is the only thing holding you back
 
  #16  
Old 11-25-2010, 02:02 AM
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^Well, you indeed were correct, after a closer inspection, we did finally find a couple unplugged wires; one of which was actually incorrectly placed, the other two completely missed. The first one I found out about when examining the clutch switches. I had wondered if maybe it wasn't starting because the computer wasn't registering that the clutch was engaged. Sure enough, I traced the wire leading from the engagement switch (there are two, for anyone who didn't know; a small one that gets activated when the clutch is pushed in, and a bigger one that gets activated when its released) and there was a connector at the end of it that was about a half inch square that had nothing connected to it. Thinking for sure that would solve the problem, I began the hunt for the missing connector and found it behind the radio/HVAC cluster. But to my dismay, it was too short to reach all the way up to where the connector was. Come to find out, some component of the radio had the same connector style and the wire we had originally connected to it was actually supposed to go up to the clutch engagement connector since it had the longer wire and the shorter wire that I had found was the one that connected to the radio component. Switched out the connectors and tried starting the car, to find that something still was wrong and it remained uncranked.

So, we began the process to tear the dash back out; fuse panel disconnected, relay panel disconnected, and then a pause from my colleague. He had found two little wires just behind the relay panel that had been pulled back a little bit when the dash originally was pulled forward to get to the heater core and when we reassembled everything, being as small as they were, were quite easy to miss. Sure enough, we plugged those in, reconnected the relay and fuse panels and battery and she roared to life.

Moral of the story: if you're going to engage in this job yourself and don't have much, if any experience at all with how the wiring is set up, it is possible to do the job yourself still, but trust me on this TAKE PICTURES of everything before you pull it apart so you have something to reference when putting it back together, it can save you a lot of headache and time.

Now, last point. Now that she's up and running again, I've encountered another problem that I'm going to start another thread about to hopefully encourage more responses on. I appear to have another electrical issue, presumably caused by all the messing about with the wiring under the dash. In a nutshell, the ABS/Brake lights are now on, and details of what conclusions I've drawn about their being on will be in the aforementioned new thread I will title along the lines of "ABS/Brake light after heater core job". If you think you may have some input on this topic, feel free to go to that thread and see if you can assist
 
  #17  
Old 11-25-2010, 02:13 AM
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yep if its you first time laber what they connected to i figured you issue was very small just one thing you forget to connect and it raises all kinds of issue's
 
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