bufbooth Posted September 28, 2015 Share Posted September 28, 2015 I replaced my alternator a few weeks ago and all appeared to be good, so I then installed my replaced heater blower and A/C evaporator. Started her up and tested the heater blower and all the vents. I then when to turn the engine off and the engine kept on running, I even took the key out and the engine kept on running. The engine finally quit after I played with the column shifter. I was able to repeat this. I then shot some WD40 in the ignition to see if that would help, but still the same issue. My first thought is that the ignition key/lock when out, but just found it strange that it happened right after I put the heater blower and A/C evaporator in. Is there anything in that area that I might of disconnected that could be causing my issue? Thanks, Dennis... Quote Link to comment Share on other sites More sharing options...
Maineah Posted September 28, 2015 Share Posted September 28, 2015 Nothing that I know of, every thing in that area should go off with the key. Quote Link to comment Share on other sites More sharing options...
jjrbus Posted September 28, 2015 Share Posted September 28, 2015 I just read about this somewhere?? If memory serves me right, somehow the new blower motor becomes a generator and kept the vehicle from shutting off. A quick test would be pull the blower fuse. Honest I am not making this up. Don't ask me how or why, just parroting something I read. Jim Quote Link to comment Share on other sites More sharing options...
zero Posted September 28, 2015 Share Posted September 28, 2015 I just read about this somewhere?? If memory serves me right, somehow the new blower motor becomes a generator and kept the vehicle from shutting off. A quick test would be pull the blower fuse. Honest I am not making this up. Don't ask me how or why, just parroting something I read. Jim It doesn't make a lick of sense to me. Even if it DID become a generator that I doubt - the blower is wired into the "accessory" circuit of the ignition switch. The ignition is wired into the "ignition" circuit. When the key is turned "off" those two circuits are totally isolated from each other. There is a way in some vehicles to get a "no shut off" condition from a bad alternator when it backfeeds via the exciter circuit. Quote Link to comment Share on other sites More sharing options...
WME Posted September 28, 2015 Share Posted September 28, 2015 Next time , unplug the alternator and see what happens. some alternators will self excite and keep the engine running. Quote Link to comment Share on other sites More sharing options...
jjrbus Posted September 28, 2015 Share Posted September 28, 2015 It doesn't make a lick of sense to me. Even if it DID become a generator that I doubt - the blower is wired into the "accessory" circuit of the ignition switch. The ignition is wired into the "ignition" circuit. When the key is turned "off" those two circuits are totally isolated from each other. There is a way in some vehicles to get a "no shut off" condition from a bad alternator when it backfeeds via the exciter circuit. It does not make any sense to me either, I almost did not post it but after 20+ years there is no telling where the blower is wired to? Simple enough to check. I did a search for the original post, not sure where I saw it? I read it on the internet so it must be true. Jim Quote Link to comment Share on other sites More sharing options...
jdfrost64 Posted September 29, 2015 Share Posted September 29, 2015 I've had this problem with my electric cooling fan. Quote Link to comment Share on other sites More sharing options...
zero Posted September 29, 2015 Share Posted September 29, 2015 I read it on the internet so it must be true. Jim Yes and Internet info usually displays on what looks like a TV screen. So it's a double whammy. Anything on a TV screen also has to be true. Quote Link to comment Share on other sites More sharing options...
Maineah Posted September 29, 2015 Share Posted September 29, 2015 The ign. switch has two sets of contacts it is possible for one to work correctly and the other one not you could try removing the bottom plastic cover around the switch starting it and unplugging the connector to the switch. Quote Link to comment Share on other sites More sharing options...
bufbooth Posted September 29, 2015 Author Share Posted September 29, 2015 Thank you for the suggestions, I will try them in the next few days. Some additional information, I did put the alternator in about a week before installing the heater blower and all was fine during that week. I have owned my Toyota for about 9 years and when I got it, it had a new (or maybe used) ignition switch in it, I have a different key for the ignition than the door has, and the old ignition switch was in the glove box. Quote Link to comment Share on other sites More sharing options...
Totem Posted September 29, 2015 Share Posted September 29, 2015 I used to have a Jeep CJ 7 that I could take the key out of when it was running; but that was without turning the keyswitch so technically the the locking mechanism that is supposed to hold the key in once the key turns passed accessory broke. My buddy's corvette stingray does the exact same thing; stays running until the key switch is turned back to "off"; with or without a key in it... In your case, the ignition switch is not killing the motor even if turned to off and the key removed. I don't think it has anything to do with gremlins, generator blower fans, electric cooling fans or even the dreaded zombie that looks like the POTUS... its simply a bad ignition switch/solenoid. Quote Link to comment Share on other sites More sharing options...
zero Posted September 29, 2015 Share Posted September 29, 2015 I used to have a Jeep CJ 7 that I could take the key out of when it was running; but that was without turning the keyswitch I have two Ford trucks that do that. I guess from wear. Like many newer vehicles - the mechanism the key goes into is not the ignition switch. The lock mechanism is separate and connects to the ignition switch by linkage. I suspect all vehicles got like that when steering wheel locks became standard. But -my 1964 Chevelle came from the factory new with a ignition switch you could remove the key from when running and not have to use a key to turn off or start if you did not want to. . So did all the 1964 Chevys as I recall. Quote Link to comment Share on other sites More sharing options...
Ctgriffi Posted September 29, 2015 Share Posted September 29, 2015 Reminds me... My ignition key is half-broken off in the lock; came that way when I bought it. I bought a pick to try and pull the lost tip back out, with no success. Anyway, as a result my truck keeps running when I pull my half-a-key out, which has actually come in handy more than once. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.