QuestionHello I have a 99 Oldsmobile silhouette ( the engine is out of a 97 about 4 years ago). When it rains it starts missing really bad and there more I drive it the better it gets. I had new plugs and wires installed by a shop and then I found a cracked coil and I replaced it. Still missing when rainy. When I got it home from the shop the next day the battery went dead. Had battery and alternator tested and both are good. (Both only six months old) I checked the alternator with a volt meter and its not charging. What else could it be? ECU?
Missing problem, maybe change other 2 coils?
Thanks for any help. This thing is driving me nuts. Thanks
AnswerHI JEFF,THEY DRIVE ME NUTS ALL DAY LONG !!! OK LETS START OUT WITH HE MISSING PROBLEM..BEING THAT THIS HAPPENS WHEN IT IS RAINING OR JUST AFTER RAIN,I WOULD THINK THE COILS ARE TO BLAME. HOWEVER TO TEST, WAIT TILL THIS ENG RUNS SMOOTH,THEN TAKE A WATER SPRAY BOTTLE AND SPRAY THE COILS,IF IT STARTS TO SKIP IN GEAR MORE THEN LIKELY THE COILS ARE AT FAULT..IF THIS HAPPENS WHILE NOT RAINING AS WELL THIS COULD BE FROM A FAULTY IGN CONTROL MODULE [ICM] YOU COULD TEST FOR SPARK COMING OUT OF EACH COIL TO BE SURE, BUT THIS IS NOT ALWAYS A TRUE TEST. THE ONLY WAY TO TELL FOR SURE IS BY DATA WITH A SCAN TOOL AND CK CYLINDER MISFIRE COUNTS...BUT COILS DO GO BAD.
NOW AS FAR AS THE ALTERNATOR NOT CHARGING. WHO CHECKED THE ALTERNATOR AND HOW ??? I WOULD HOOK YOUR VOLT METER UP TO THE BACK OF THE ALT AGAIN BAT POST POSITIVE AND GROUND THE OTHER LEAD AT THE BATTERY IF YOU WANT. SHOULD HAVE 13.8 TO 14.4 VOLTS WHILE RUNNING AT 1500 RPM WITH LIGHTS ON. IF LOWER THEN THAT THEN YOU ARE CORRECT..CK TO MAKE SURE YOU HAVE 12 VOLTS AT THE BIG WIRE AT THE ALT,UNPLUG THE SMALL WIRE CONNECTION ON THE ALT AND CK FOR POWER WITH A TEST LIGHT WITH THE KEY ON. SHOULD HAVE POWER THERE AS WELL AND THE BATTERY LIGHT SHOULD LIGHT UP ON THE DASH WHEN CK FOR POWER ON ONE OF THOSE TERMINALS,,OR JUST LEAVE THE PLUG IN AND TURN THE KEY ON TO MAKE SURE THE BATT LIGHT DOES LIGHT UP. IF IT DOES LIGHT AND YOU HAVE BATTERY VOLTAGE TO THE BIG WIRE AT THE ALT ,THE ALT IS NO GOOD. ONE LAST THING,MAKE SURE THE DRIVE BELT IS NOT LOOSE OR SLIPPING.SO LETS SAY YOU DON'T HAVE POWER ON THE SMALL WIRE CONNECTOR AT THE PLUG OR NO 12 VOLTS ON THE ALTERNATOR PLUS TERMINAL..YOU HAVE TO CK YOUR WIRING HARNESS,FUSE-ABLE LINK TO THE ALT MAIN PLUG. THESE LINKS ARE USUALLY AT THE BATTERY CABLE [PLUS CABLE] OR DOWN AT THE STARTER MAIN TERMINAL... LET ME KNOW WHAT YOU FIND AND WE WILL GO FROM THERE,, AND GOOD LUCK,,TOM
