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GOT_NITRO? Enthusiast

GOT_NITRO?

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I WAS HAVING A GREAT DEAL OF TROUBLE FINDING THE CAUSE OF A RANDOM MISFIRE IN MY YUKON BUT I FINALLY FIGURED IT OUT. I EVEN BOUGHT THE AUTOTAP SCANNER TO READ THE LIVE DATA!!! I FIGURED THAT THE CAP AND ROTOR COULD NOT BE THE CULPRIT SINCE I REPLACED THEM A FEW MONTHS BEFORE THE PROBLEM STARTED. THEN I DECIDED TO CHECK FOR THE CLOGGED VENT HOLES IN THE DISTRIBUTOR AND IT WAS FAIRLY CLEAN. THE DISTRIBUTOR WAS COMPLETELY CORRODED WITH GREEN GROWTH ON ALL OF THE TERMINALS. I'M THINKING "WHERE DID THIS COME FROM"????? THEN I FIGURED IT OUT......I INSTALLED A COWL INDUCTION HOOD AND NEVER REPLACED THE UNDERHOOD MATTING. WELL, OVER TIME, MOISTURE GOT INTO THE DISTRIBUTOR AND CORRODED THE NEW CAP AND ROTOR. IF YOU HAVE A COWL INDUCTION HOOD WITH THE VENT HOLES FACING THE WINDSHIELD I WOULD SUGGEST USING THE UNDERHOOD MATTING. ALSO, MAKE SURE THE SEAL IS IN PLACE ALONG THE BACK OF THE HOOD WHERE IT MEETS THE COWL TO KEEP MOISTURE OUT. THESE DISTRIBUTORS ARE VERY SENSITIVE TO MOISTURE. :ughdance:

GOT_NITRO? Enthusiast

GOT_NITRO?

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Thanks! It runs much better. I am noticing a noise that I'm certain is coming from the brake booster but only on cold days (under 30 degrees). It is a groaning type of noise at start up (about 2 - 3 seconds long). The noise then quiets down and is barely audible and then disappears after about 20 - 30 seconds of warm up. It is definately an air / diaphram type of sound. The vehicle still stops good. I'm wondering if it is a brake booster or check valve going bad or an abs issue????? Any suggestions or tests I can perform???????

GOT_NITRO? Enthusiast

GOT_NITRO?

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I had the SAME EXACT thing on my tahoe!!! Except i never changed my hood.

 

What Vent holes are you talking about?

 

 

 

 

The vent holes are located in the base of the distributor. Mine did not have any screens. Mine looked more like overlapping plastic tabs. I've heard that GM revised the design but I do not know if I have the new design or the old one.

budhayes3 Senior Enthusiast

budhayes3

Posted
Posted
Thanks!  It runs much better.  I am noticing a noise that I'm certain is coming from the brake booster but only on cold days (under 30 degrees).  It is a groaning type of noise at start up (about 2 - 3 seconds long).  The noise then quiets down and is barely audible and then disappears after about 20 - 30 seconds of warm up.  It is definately an air / diaphram type of sound.  The vehicle still stops good.  I'm wondering if it is a brake booster or check valve going bad or an abs issue?????  Any suggestions or tests I can perform???????

 

 

 

 

Could be a check valve or diaphrarm issue, or there may be some sort of moisture in there also that is actually freezing up overnight. Some older Toyota Tercels and Paseos had an issue with moisture getting into the brake booster hose and causing a similar concern. You might want to check the hose and replace the underhood weaterstrip for starters.

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