Conference vmsnet::car$note:carbuffs

    Hello,           
    
    I need some assistance on where I might best get this problem solved.
    
    I have a 1986, Chevy Nova, auto, 4 dr, ac with 161K miles.  For
    some time now, the car responds negatively to damp/rain conditions.  
    Wires have been changed, plugs, dist. caps, rotar's, air filters, oil 
    changes and the problem still exists.
    
    Example:  I'm traveling East on Rte 290, doing about 55mph at 11pm.  
    Clear night, at about 2 miles from the 495/290 connector, I drive 
    through a small patch of fog. The car speed drops from 55 to 45.  I
    press the gas pedal, nothing happens, the car does not go faster,
    this continues approx 2miles and I continue to press down in small
    amounts on the gas pedal.  Just after the highway connector, what
    ever is the problem with the car is gone, and I've got the car back
    to doing 55mph.  
    
    Another example:  Neil drives the car to the Assabet Tech school
    here in MRO.  We live about 1.5 miles away.  It's pouring rain,
    the car starts up okay, continues to run okay.  We get to the school 
    and drive slowly around to the Auto Dept.  Neil stops the car at 
    the speed bump, the car dies.  It takes approx. 2 minutes of starting 
    the car, putting it into gear, having it stall and repeating this
    process until the car stays runing.  Get to the next speed bump, same 
    problem.    
    
    The mechanic teacher does not put the car on the computer that day.  He
    was to put the car on the computer in Field Test Mode (according to the
    mechanic at the local Midus shop who told me that Nova's were known to
    have this problem.) He does it the next day and can not duplicate the 
    previous day's activity of the car. Due to today's high cost of 
    having repairs done at dealerships I have not taken the Nova to a 
    Chevolet Dealer.  I attempted to take it to a Toyota Dealership and 
    was told, "WE DON'T WORK ON CHEVY NOVAS'!" There is hardly any part 
    of the car that is Chevy!
    
    Anyway, Do the above examples sound familiar to anyone here that 
    is or was a Nova owner that had this type of problem and was able 
    to get it fixed? Or, a mechanic that is familiar with Nova's If so, HELP!!!
    
    We would appreciate any recommendations of mechanics that were able to
    fix the above problem for you, located anywhere  in the general Rte 128 
    to Leominster/Franklin/NH areas. 
    
    I can be reached at the above VAXmail address or [email protected]
    or dtn: 276-9256.
    
    Thank you.
    Marie McCallion
                  

    
    Re .417: I had almost exactly the same car (standard on mine) with what
    sounds like exactly the same problem. It started at about 120K, stopped
    at around 130K. I think the trick was dousing the entire engine
    compartment (not just plug wires, distributor, etc) with a can of
    spray silicone; however, I was trying so many things and the problem
    was so intermittent that I never could put my finger on the exact cure.
    
    As for reliable Chevyota Novolla mechanics, I highly recommend First
    Class Import Autos, on Mass Ave (Rt 2A) in Lunemburg; Roger is the
    proprietor.
    

    One evening as it's getting dark, take a spray bottle with water.
    Run your car and let it warm up.  Pop the hood, and start misting
    the water around different spots, most likely around critical parts
    of the car, ignition, any sensors, etc...  Do this carefully and
    slowly and note if/when the engine changes pitch or dies and where you
    misted the water.  Since the sun is going down, you will be able
    to see any arcing, or blue flashes/spark(s) if there is an electrical
    problem.  The water mist might make any arcing situation worse.  You
    should also hear a slight "click" if/when the spark happens.
    
    This will help you isolate the location of any fault(s).  Most likely
    I'd concentrate around the ignition.
    
    The silicone or dielectric grease might cure the problem once you
    find the location of the problem.
    
    Regards,
    MadMike

    
        The following should be checked only if you have a carburated
     engine.
    	There have been cases (I had one) where you can, under conditions
     you mentioned get carburator Ice. (I know, I know, It only happens in
     airplanes, Right?......Wrong!)
    	You can check a couple of things.
    	1. see if there is a wire (or pair of wires) that go to the base
      of what looks like large gasket under the carburator. This is a
    heater that warms the carb/plenum chamber to ward off icing. If this
    circuit is open, there's your culprit.
    	2. Check that the heater crossover ports are not blocked.
    Unfortunately this can only be checked by taking the carburator off the
    car and checking the openings (this is a small crossover port cast in
    the intake manifold allowing heated air to warm the carb body)
    
       If you have fuel injection *theoretically* carb ice can't form so
    forget the above.
    
      Good hunting,
      Bob
    

    I had never heard of fuel injection icing until my private written...
    that was 1 of 3 wrong. 

	I have this 86 Chevy K10 fullsize Blazer 4WD that started running very
 badly this weekend...... It's a 305, 4 barrel carb, auto 4spOD......

	Here's a little history, last Thursday I started a tune up on it.
 Did the plugs, wires, Dist. cap/rotor, fuel filter... Simple, right.....
 Turned the key, crank, crank, crank, nothing. Investigate, and found no
 spark. Bummer. Retrace all my steps, and nothing. The old cap was badly
 burnt at the center electrode (wear?? over voltage/current??), so I could
 not put it back on.... Tried two other caps with coil and still nothing.
 The fix was to replace the whole distributor, probably because of a bad
 module/pick up, plus mine had some oil in it.........

	Got the new Distributor installed, timed, etc. and the Blazer was
 running strong and smooth.... Great job I thought...... 

	Yesterday, I was driving the Blazer from Fitchburg to Littleton,
 Hudson MA., back to Leominster. I had made a few stops, but it always
 restarted, and ran fine until I got on Airport road, and all of a sudden
 it started skipping/sputtering/pinging...... Pull over, shift in neutral,
 idles fine, revs up fine..... Put it back in drive and back to the skipping/
 sputtering/pinging, no power....... I babied the thing all the way home, and
 parked it in the driveway......

	Opened the hood, everything looks OK, no broken hoses, could hear
 a vacuum leaks..... Turn the key, the things purrs, revs up fine when
 tapping the gas pedal. Put the brake on, shift in reverse, and it seems it
 wants to go, neutral, runs fine, drive is back to skipping/sputtering/
 pinging..... ;-(

	I'm planning on working on it after work, but I would appreciate
 any ideas. This thing was running fine, and just crapped out for no reason.

	Some of the thing I plan to check are, timing to see if it moved,
 fuel filter for dirt, and volume out of the pump, check the dist cap/rotor
 for burnt spots, and make sure the distributor didn't fly apart. Could it
 be the tranny/torque conv. killing it.

	Thanks

	Norm

                      <<< Note 31.422 by NETCAD::NPARE >>>
                    -< Help needed with a Chev. Blazer.... >-



>>	Opened the hood, everything looks OK, no broken hoses, could hear
>> a vacuum leaks..... Turn the key, the things purrs, revs up fine when
>> tapping the gas pedal. Put the brake on, shift in reverse, and it seems it
>> wants to go, neutral, runs fine, drive is back to skipping/sputtering/
>> pinging..... ;-(

	This should read "could not hear any vacuum leaks".....

	Thanks

	Norm who's fingers cannot type what his brain tells them ;-)

    Check seating on the plug/coil wires.  mist the wires and see if the
    things get worse.  Check if one of the plug wires is touching some
    sharp bit of metal.  Then, pull the dist. cap.  check the rotor, if it
    is intact, pull each plug individually and check for fouling.  
    
    Lastly, check the compression.  
    
    Dave
    

	  Yesterday afternoon was a great afternoon to do work on the Blazer
 in .422. So I took out the plugs, the plugs look/are new, checked the gap
 .045 as per the engine sticker, perfect, ohm'd the wires, good (new Belden's),
 checked the firing order, per listing on the intake manifold, checked the
 fuel filter, no gunk and properly inserted. I didn't think I could screw
 that up ;-).......

	Unpluged the battery, took the dist. cover apart for a check.
 No carbon tracks, cracks, rotor looked fine/new, checked coil per Chilton
 (they didn't give ohm measurements, just where continuity/no-continuity
 between terminals/contacts) looked/seemed OK, the distributor is a new
 rebuilt still looked brand new, so I re-assembled the whole thing.

	Re-connected the battery, installed my tach/dwell meter, timing light
 to check timing...... Turn the key, and crank, crank, crank..... What the
 %^_*)*(..... Checked for spark, nothing..... The dist has 12 volts at the
 battery terminal...... It looks like that the truck ate another module
 (in the dist)........

	Questions, Could the ECM (86 Blazer 305 auto/4wd carburated) burn
 out another module????

	Could the coil burn out the module??? A new distributor complete
 with pick up/module fixed the problem the last time, but only for one day.

	Could the coil burn out the module and/or the ECM????

	After re-thinking the whole scenario, which I thought could be
 maybe related to weak spark or lean fuel condition, it now point to weak
 spark. Something like what happens when you have a wet ignition system......

	What else could cause this condition???? Is there a better way to test
 the coil????

	I could shotgun this and replace the distributor/module, ECM, Coil,
 dist cap/rotor (again), but would rather replace only the right parts/cause.

	Thanks

	Norm

 PS: Didn't check the compression, but I seriously doubt that I blew a whole
     in every piston, and this thing was purring, does not burn oil.....
     Oh yeah, mileage is 55,300mi. (documented) and looks it per condition.
    

    
    I can't speak for your particular engine/ECM, but if your
    setup has a ballast resistor between the ECM and coil
    (as most do) this could be the problem.  Hook an ammeter
    in series with the coil if possible and see if any current
    flows when ignition is on then when you're cranking the engine.
    If neither you may have problems with an open wire, bad connector,
    bad ballast, ECM problem, or something related.  If the juice 
    stops when you're cranking your starter solenoid or ignition 
    switch may have a problem.  It's possible the ignition
    module isn't blown - just that you have an electrical
    problem in the same circuit.
    
    Good luck,
    
       Jim D.
    
    

	rep -.422, .425 Sick Blazer......

	Well last Thursday I finally found what the real fix to the
 problems that I had with my Blazer, not without a cost though.....

	I picked up another new/rebuilt distributor, new coil, new
 dist. cap/rotor. Installed all the parts, and reconnected the wires
 to the + terminal of the coil. One of the wire had a fusible link,
 and by accident, noticed that the insulation stretched when I barely
 tugged on it...... Upon further inspection, the wire had two breaks
 and I spliced/solder/crimped it back together, and it fired up. I ran
 it through the weekend, and it's still running, so I believe it is
 fixed.

	While thinking about it, I now believe that the last person that
 tuned the Blazer, pinched the wire, and the cap kept it running. When
 I did the tune up, I made sure nothing was pinched, but inherited
 the intermittent problem ;-(.....

	I could have brought the parts back (tried anyway), but my
 original distributor had oil in it, and would have needed to be
 replaced at one point. The dist. cap/rotor/coil, well they are
 new now...... In all, that broken wire cost me an extra $150.00
 ;-(........ If I knew where it went, I probably would have ohm'ed
 out. The other wire was fine, and I had 12V that the coil, so it
 didn't look suspicious....

	Live and learn.....

	Thanks for all the ideas, and hope this will help someone
 else someday.......

	Norm

re: -1

BTW, any idea what caused the link to part in thre first place? Could there
still be a problem hiding somewhere?

Jim

>>          <<< Note 31.428 by BIGQ::HOWLAND "Kskamiwi Kwen� Tewkw�k" >>>
>>                               -< fusible link >-

>>re: -1

>>BTW, any idea what caused the link to part in thre first place? Could there
>>still be a problem hiding somewhere?

>>Jim

	Jim,

 It wasn't the link that broke, it was right at the end of the link. I had
 to trim back some plastic to be able to crimp the wire back together. I
 believe that maybe the wire got pinched in the distributor cap, when the
 thing got it's last tune up...... It's still running, and I'm keeping my
 finger crossed ;-).....

	Norm

    	HI NORM, If I where you, i'd hit a parts store and get
    	a replacement and have it in the car. Its gonna suck
    	when it breaks in the most inconvient time.  been there.
    	My sons 71 scamp just did the same thing last week.
    dave

Norm,,
	Great! My misunderstanding. Good luck.

Jim

	Hi,

 I have another (well possibly a few) question(s) on that 86 full size K10
 series Blazer 305 4b Carb, auto tranny, AC...... I believe that it is a
 half a$$ computer control engine (electronic HEI ignition with a ECM behind
 the glove box), no O2 sensor.......

	Since the last tune up (ref a few notes back.422-423), where I
 replaced the cap, rotor, coil, distributor, wire, plugs, I have inherited
 pinging when I first step on the throttle once warmed up. Not sure if it
 was there before since the truck is still fairly new to me...... It happens
 when cruising at any speed, and just cracking the throttle to maintain speed.
 If I let off or stomp on it, the pinging goes away.......

	The timing was set per the sticker/book at 4'BTC, then I tried
 backing it  to 6'BTC, and still the same. I run 89 octane Getty fuel, and
 tried adding some 93 octane Getty, but it will take some time to use up
 30 gal only driving it part time ;-)..... It idles fine (smooth), the pick
 up feels good (no hesitation), starts fine when cold/warm, so I don't
 think that it's a carburation problem.

	I remembered reading in here about the EGR valve causing knocking
 at slight throttle increase, so I search this file, read the string about
 the EGR valve, it's operation, but the string said that if it was leaking/
 stuck, it would cause idle problem (which I don't have). It did mention some
 knocking/pinging at cruise with surging though, but I didn't get that warm/
 fuzzy feeling that replacing the EGR would be the cure (I could be wrong)....

	So, does anyone have any ideas on what could be causing this
 pinging/knocking???? As I said, the Blazer seems to be running great, except
 for this pinging, and I woud like to get rid of it before it destroys
 something else......

	Thanks

	Norm

 PS: Oh yeah, the operating temp per it's gauge is at 190'F (1/3rd of the
     way up).......

    Did you disconect the multi pin connector that goes to the( distributor
    /Ingnition?) before setting the timing? If not your 6 degrees could be
    actually 18 or something like that.
    						JK

>>                     <<< Note 31.433 by FABSIX::J_KASPER >>>
>>                                 -< knocking >-

>>    Did you disconect the multi pin connector that goes to the( distributor
>>    /Ingnition?) before setting the timing? If not your 6 degrees could be
>>    actually 18 or something like that.
>>    						JK

	JK,

 Is this the connector (4 pin in the back that I believe goes to the ECM,
 not the ones that goes to the Bat/tach)???? 

	No I didn't..... There was no mention in the Chilton (I'll have to
 re-read the procedure)...... I recall hearing somewhere that the Blazer will
 run with that connector unplugged, but I don't remember the context of the
 conversation, or if it was about timing.

	Also, I figure the you disconnect that 4 pin plug, plug the vacuum
 advance, etc, start the Blazer, set the timing while in drive, kill the
 engine, put everything back together, and I'm done.... Correct????

	Thanks

	Norm

    Norm, I dont believe you set it in gera only in park or neutral.
    By disconecting the connector you remove the ecm from controlling the
    timing advance at idle. I have not done this proceedure for a couple of
    years so it would be best to call a mechanic that may be sure.
    The car I had to do was a 1984 trans am with the 305 ho chevy.
    
    If I remember when you reconnect the connector the timing advances
    aprox. 6 to 8 degrees?
    
    					Good luck  JK

    I have a running, 2.8 liter fuel injected engine in a camaro.
    What is something like that worth?  I'm selling it 100% complete.
    Everything, including the harness/ecm/etc... to make this thing work.
    
    Better yet... does anyone need a V6 in here?  name your price, within
    reason.
    
    MadMike

    While i'm on this topic, let me say this:
    
    The car currently has a FI V6 in it.  It's getting a 305 with a holley
    doublepumper, and whatever the SCCA AS rules allow.  This is why I can
    ditch all the electronics, since nothing will be left.
    
    On a swap like this, in order to give/keep the brains of the V6, what
    sorts of things need to come out, besides the ECM.  How do I
    selectively remove the sensors and stuff to keep them available to
    be wired into the recieving car?  Assuming the recieving car doesn't
    have the electronics to take the FI?
    
    MadMike