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Discussion Starter #1
Hello all,
Well, it's been a few weeks and Daisy (the '87 RRC I have referenced in previous posts/threads) has been running like a champ.
I mentioned earlier the high idle surge (starts, runs up to about 1500, then idles down to 650-700 within 10 secs or so) that she does at every startup. Some folks said that's normal, they all do it. OK, maybe so. But...
I've owned this rig since 2002 and it never did this before all my recent work. Now maybe the IAC was sticky. Maybe some connection was weak, maybe the moon was not in the correct phase, but this behavior is new.
So my question to all is, "Does your RRC do this?" Also, if yours does not, then "Is this normal?"
Normal or not, kind of annoying. Sounds like the throttle is stuck or my foots on the gas or I'm prepping for a burnout or something every time I fire the rig up.
Thanks to all who chime in.
 

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timing helps a little bit but in reality high idle at start up is nature of the beast, 14cux is programmed to do so. as key turns on 14 cux ecu powers up, performs an internal check of sensors and systems, resets idle valve to zero, primes fuel pump.
key goes to engine start position, engine turns, ecu receives spark pulse signal, fuel pump activates, air temp is measured by maf, ect sensor tells ecu it is cold, ecu extends injector duty cycle.
this last duty cycle floods the engine, engine starts but idle valve is at zero. this allows engine to idle at max which in turn clears the flood condition, in the following milliseconds IAC recalibrates to stored value and begins idle down to normal idle.
this repeats it self every time engine starts as it is built in default.

do a search for "mark adams rovergauge" this brings up lots of good reading on lucas 14cux engine management, dispels a number of myths and explains in full detail how and why it works the way it does.
 

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/\ A very compressive answer indeed. Mine does it to and now I know why!
 

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Discussion Starter #4
95classiclwb, thanks for the great explanation. I now wonder if part of the puzzle of "why does it do it now but didn't before" is related to that I now am running the 14cux system. I guess I'll just have to come to accept it as one of the manyendearing idiosyncrasies that come with RRC ownership!
 
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