TOM WALKER wrote to ROY WITT:   
      
    RW> TW>> IT lowers the emmissions, In fact California requites a higher   
    RW> TW>> engine temperture to LOWER the enissions   
      
    RW>> Nobody cares what CA requires, except law abiding Californians. The   
    RW>> rest of us use lower temperature thermostats in our cars. I used a   
    RW>> 180 in my Z28 when I lived in CA. Some people I knew at the time   
    RW>> also had altered their exhaust to eliminate oxygen sensors in the   
    RW>> exhaust, in an attempt to increase fuel/air ratios. Some even   
    RW>> removed the cats...   
      
    TW> You made a statement "implying" that Higher Engine temperature Raises   
    TW> Emissions. I mearly rebutted that statement saying it actualy LOWERS   
    TW> it.   
      
   I didn't say any such thing. Not to mention that all of those guys who   
   have 180 thermostats in their cars and have removed the Cats still pass   
   emissions tests, IN CALIFORNIA...if the test stations even thought that a   
   Cat was removed, the cars wouldn't pass the visual check.   
      
    RW> RW>>> If you have a better explanation, I'm all ears.   
      
    RW> TW>> Well the Engine Block switch and the AC fan control are two   
    RW> TW>> seperate circuits and should not interfere with each other.   
      
    RW>> After consulting the factory Service Manual, I'm going to stick by   
    RW>> my statement.   
      
    RW>> /quote   
    RW>> Engine Electric Coolant Fans   
    RW>>  Coolant fan operation is crucial to the proper operation of the air   
    RW>> conditioning system. The coolant fans ensure the proper amount of   
    RW>> air flow acrosss the condenser throughout the vehicle operating   
    RW>> range.   
      
    RW>>  Fan operation should be checked during any air conditioning   
    RW>> diagnosis procedure. Special attention should be given to the fan   
    RW>> wheneve excessive high side pressures are encountered. /unquote   
      
    TW> That quote has nothing to do with the Engine Block heat switch and   
    TW> the operation of the Fan to pervent engine overheating.   
      
   On the contrary...   
      
    TW> IF your FAN was not responding the the engine block temperature   
    TW> switch you had ANOTHER problem totally indepebndent to what the AC   
    TW> system was reporting.   
      
   Wrong.   
      
    RW> TW>> NOT being a Chevrolet Fan I got this from www.camaroz28.com on   
    RW> TW>> coolant fan not runing if AC looses charge   
      
    RW> TW>> ****   
      
    RW> TW>> There are 7 things to consider:   
    RW> TW>> (the first 4 are ruled out because you said that the fan worked   
    RW> TW>> when the A/C was working.) Item 5; either the coolant   
    RW> TW>> temperature isn't reaching 238øF, or faulty wiring to the relay.   
    RW> TW>> Item 6; ECM fan driver may be bad. unforunately the ECM will   
    RW> TW>> need replacing. Using an adjustable temp switch (for   
    RW> TW>> winter/summer) would save you the trouble of buying a new ECM,   
    RW> TW>> but you'll lose the control the ECM has for different   
    RW> TW>> conditions.   
      
    RW>> Neither of these are what is happening. The coolant temp doesn't   
    RW>> ever go to 238F in any case. Even if you have a factory 195F   
    RW>> thermostat, it won't go that high. And, since the system works as it   
    RW>> is supposed to work when it is charged, I don't believe for a minute   
    RW>> that there is anything wrong with the system (other than a system   
    RW>> leak).   
      
    RW>> You cannot perform a fan operation check without certain diagnostic   
    RW>> tools, as specified by GM.   
      
    TW> Than why is it suggested you Ground the Wire GOING to the Block Fan   
    TW> switch to see if the FAN would run?   
      
   You must be using older, before OBD I, information.   
      
    TW> WHICH it should, THEIR WORDS NOT MINE!!!!   
      
   I'll use the 1998 Service Manual to diagnose and repair what their testing   
   reveals...it specifically applies to the 1998 product rather than some   
   generic unknown source.   
      
      
            R\%/itt   
      
      
   --- GoldED+/W32 1.1.5-31012   
    * Origin: Texas Lone-Star - Texan, American, USAian  (1:387/22)