1991 Geo Storm Engine Problems

7 MONTHS AND 5 REPLACEMENT ECUS ON MY 1991 GEO STORM GSI, AND STILL HAS DANGEROUS ISSUES OF STALLING ON HIGHWAY AND WHEN PULLING OUT INTO TRAFFIC. THE PROBLEM IS THAT BETWEEN 1985 AND 1995, AC DELCO USED A INSULATIVE SPRAY ON THE CIRCUIT BOARDS IN THESE ECUS/COMPUTERS WHICH SHRINKS OVER TIME WHEN EXPOSED TO WARM AND COOL TEMPERATURE CONDITIONS, SUCH AS THE NORMAL CONDITIONS THAT AN AUTOMOBILE IS SUBJECTED TO. THE SHRINKING INSULATIVE SPRAY CONTRACTS AND PULLS THE ELECTRONIC COMPONENTS FROM THE CIRCUIT BOARD, BREAKING SOLDER CONNECTIONS AND CAUSING SHORTS. THE SYMPTOMS OF THIS FAULT ARE MOST NOTABLY ERRATIC IDLE, IDLE REVVING AND DROPPING, IDLE DIPPING OFTEN WITH ENGINE DYING, IDLE HANGING HIGH ABOVE 2,000 RPM, AND ENGINE DYING OR STALLING FOR NO REASON WITH NO TROUBLE CODES. GM KNOWS ABOUT THIS FAULT IN THEIR AC DELCO ECUS/COMPUTERS AND HAS EVEN GONE SO FAR AS TO INCLUDE SUPPLEMENTAL INSTRUCTIONS ON HOW TO TEST FOR SHORTS AND BROKEN CIRCUITS IN THE ECU/COMPUTER TO THEIR TECHNICAL LITERATURE, THOUGH THEY REFUSE TO REPAIR OR REPLACE THE PROBLEM AT THEIR OWN EXPENSE. GM WENT FURTHER AND BEGAN USING A DIFFERENT INSULATIVE SPRAY ON ALL OF THEIR ECUS/COMPUTERS IN 1996, THOUGH THEY DO NOT USE THIS NEW SPRAY ON THEIR FACTORY RECONDITIONED ECUS/COMPUTERS FOR THE GEO STORM MODELS. *TR

TL* THE CONTACT OWNS A 1991 GEO STORM. THE CONTACT STATED THAT THE VEHICLE STALLED WHILE SITTING AT A TRAFFIC STOP. THE VEHICLE WAS TAKEN TO THE DEALER HOWEVER, THEY WERE UNABLE TO REPAIR THE VEHICLE. THE MANUFACTURE WAS MADE AWARE OF THE FAILURE. THE VEHICLE WAS NOT REPAIRED. THE APPROXIMATE FAILURE MILEAGE WAS 40,000.

THE VEHICLE STALLED WITHOUT WARNING. THE DEALER REPLACED THE DISTRIBUTOR CAP, SPARK PLUG WIRES AND ROTOR, HOWEVER THE PROBLEM RECURRED. *JB

ONGOING PROBLEM WITH ENGINE STALLING / CUTTING OFF WHILE DRIVING AT MULTIPLE SPEED. VEHICLE BEEN TO DEALER, BUT PROBLEM REOCCURRING. FEEL FREE TO PROVIDE ANY FURTHER INFORMATION.*AK

WHEN I START THE CAR WITH THE ENGINE COLD, AS SOON AS THE CHOKE TURNS OFF, THE ENGINES DIES, I HAVE TO TAP THE ACCELERATOR TO KEEP THE ENGINE RUNNING. ONCE THE ENGINE IS OPERATING TEMPERATURE, I SHIFT THE TRANSAXLE INTO PARK, AND THE IDLE SHOOTS UP TO 2000 RPMS, THE ENGINE IDLES UP AND DOWN WHILE THE CAR IS IN PARK. THE IDLE ALSO DROP TEMPORARILY WHEN THE BRAKES ARE DEPRESSED THIS STARTED HAPPENING DURING THE LAST WEEK WHEN THE WEATHER TURNED HOT FOR THE SUMMER.*AK

ENGINE CONTROL COMPUTER IMPROPERLY BUILT CAUSING ERRACTIC IDLE FROM 2000RPM TO 500RPM, CAR STALLS AND WILL NOT START. ISUZU HAS BEEN CONTACTED ABOUT THIS AND HAS STATED"WE DO NOT MAKE CARS" AND THEY FAIL TO RECTIFY THE PROBLEM. THERE ARE VERY MANY OF US WHO WOULD LIKE TO SEE THIS ISSUE RESOLVED AS OUR CARS STALLING IN TRAFFIC AND IDLING ERRACTICALLY IS CAUSING A LOT OF PROBLEMS AS IN POOR EFFICIENCY AND UNNEEDED DOWNTIME. THE PROBLEM IS IN THE INSULATIVE SPRAY ON THE MAIN CIRCUIT BOPAR DOF THE UNITS THAT BREAKS DOWN OVER TIME DUE TO HEAT AND EXTREME(HOT OR COLD) TEMPS. GMC HAS RECOGNIZED THIS PROBLEM AND FAILS TO DO ANYTHING ABOUT IT. WE WOULD LIKE THIS ISSUE ADDRESSED AND I SPEAK FOR THE OVER 500 MEMBERS OF THE GEO STORM OWNERS CLUB, WWW.STORMOWNERS.COM. *AK

EXPERIENCING PROBLEM WITH VEHICLE STARTING ITSELF AND ENGAGING OUT OF OUT OF GEAR ( W/O KEY AND VEHICLE WOULD BE COMPLETELY OFF). CONDITION HAVE OCCUR ON FOUR OCCASION WITHIN A WEEK. VEHICLE WILL BE TAKEN TO THE DEALER FOR INSEPECTION. PLEASE PROVIDE ANY FURTHER DETAILS.

GM & ISUZU ARE AWARE OF THIS. APPARENTLY THEY HAVE REFUSED TO FIX IT. MY CAR HAS JUST BEGUN THESE SYMPTOMS BUT I DON'T WANT TO WAIT UNTIL THE CAR DIES ON ME. THIS YEAR WE HAVE HAD RECORD HIGHS IN CA. IT'S MAKING THE PROBLEM WORSE. IT CUTS OFF WHEN IT FEELS LIKE IT FOR NO GOOD REASON. IT IDLES HIGH AND LOW. IT HAS EVE REFUSED TO START AT TIMES.*AK

FROM THE TIME THE VEHICLE WAS PURCHASED THE CAR HAS IDLED ERRATICALLY WHILE SITTING STILL, AND SOMETIMES WHEN IT WAS COLD. *AK

AT AN IDLE, IN PARK OR IN GEAR, THE ENGINE SPEED OFTEN RISES FROM NORMAL (1000RPM) UP TO AS HIGH AS 4000 RPMS. THIS HAPPENS AT A STAND STILL AND ALSO WHEN APPROACHING, SITTING AT OR LEAVING STOPP LIGHTS ALSO. THIS PROBLEM HAS CAUSED UNWANTED AND UNSAFE "LURCHEING" FORWARD WHEN LETTING OUT THE CLUTCH. AT TIMES, WHEN THE ENGINE SPEED COMES BACK DOWN, IT WILL DROP TOO FAR AND CAUSE THE ENGINE TO STALL. THIS HAPPENED TO ME IN THE MIDDLE OF A BUSY INTER SECTION AND I WAS NEARLY REARENDED. TO MY KNOWLEDGE GM IS AWARE OF THIS PROBLEM BUT REFUSES TO TAKE CARE OF IT OUTSIDE NORMAL WARRANTY PERIOD.*AK

ENGINE MANIFOLD EXHAUST PIPE FAILED AND REPLACED.

CONSUMER REPLACED EXHAUST PIPE ONCE, AND CURRENTLY VEHICLE NEEDS EXHAUST PIPE REPLACED AGAIN, VEHICLE HAS HAD AN EHAUST LEAK.*AK CONSUMER HAS SINCE REPLACED EXHAUST PIPE.*JB

OWNER SAID THAT THE EXHAUST SYSTEM WAS DESIGNED POORLY, IT IS CRACKING AND SPLITTING. *AK

EXHAUST MANIFOLD LEAKS FUMES INTO THE PASSENGER COMPARTMENT. TT EXHAUST MANIFOLD WAS BROKEN IN HALF, LEAKS EXHAUST FUMES INTO ENGINE AND PASSENGER COMPARTMENT. *YH

EXHAUST MANIFOLD HAS CRACKED ON VEHICLE. TT

EXHAUST MANIFOLD IS CRACKED. VEHICLE HESITATES, BUCKS AND JERKS. TT

EXHAUST MANIFOLD CRACKED.

ERRATIC IDLE SPEED THAT REVS AND DROPS WHILE YOU ARE COASTING OR AFTER YOU COME TO A STOP. SOMETIMES IT REVS HIGH INTO THE RPM RANGE ABOVE IDLE SPEED, SOMETIMES IT DROPS SUCH THAT THE ENGINE NEARLY DIES OR DOES DIE. HOVERING IDLE SPEED THAT HANGS AT CRUISING LEVEL WHILE YOU ARE COASTING OR AFTER YOU HAVE COME TO A STOP, USUALLY 2,000-3,000 RPM. SOMETIMES, IF YOU WAIT A WHILE, IT COMES DOWN ON ITS OWN, SOMETIMES IT DOES NOT.HOVERING IDLE SPEED THAT HANGS AT CRUISING LEVEL WHILE YOU ARE COASTING OR AFTER YOU HAVE COME TO A STOP, USUALLY 2,000-3,000 RPM. SOMETIMES, IF YOU WAIT A WHILE, IT COMES DOWN ON ITS OWN, SOMETIMES IT DOES NOT. ISUZU AND GEO HAD IN THE PAST (ONLY WHILE THE CAR WAS UNDER WARRANTY) REPLACED THE ECU TO SOLVE THE PROBLEM. ISUZU AND GEO HAD IN THE PAST (ONLY WHILE THE CAR WAS UNDER WARRANTY) REPLACED THE ECU TO SOLVE THE PROBLEM. IT IS MOST DANGEROUS ON THE AUTOMATIC MODELS BECAUSE THE AUTOMATIC TRANSMISSION USES ENGINE SPEED AS A REFERENCE TO CONTROL THE ENGAGEMENT OF THE TORQUE CONVERTER (IF THE ENGINE SPEED IS ABOVE 900 RPM, THE CAR MOVES FORWARD) SO HOVERING IDLE SPEED IS OF GREATEST HAZARD TO AUTOMATICS. IT IS ALSO A HAZARD FOR MANUAL TRANSMISSION CARS BECAUSE ENGAGING THE ENGINE AT 2,000-3,000 RPM WILL RESULT IN VIOLENT FORWARD MOTION. IT IS MOST DANGEROUS ON THE AUTOMATIC MODELS BECAUSE THE AUTOMATIC TRANSMISSION USES ENGINE SPEED AS A REFERENCE TO CONTROL THE ENGAGEMENT OF THE TORQUE CONVERTER (IF THE ENGINE SPEED IS ABOVE 900 RPM, THE CAR MOVES FORWARD) SO HOVERING IDLE SPEED IS OF GREATEST HAZARD TO AUTOMATICS. IT IS ALSO A HAZARD FOR MANUAL TRANSMISSION CARS BECAUSE ENGAGING THE ENGINE AT 2,000-3,000 RPM WILL RESULT IN VIOLENT FORWARD MOTION.

ENGINE IDLES UNCONTROLABLY AT HIGH RPMS (2000+) WHEN STOPPED, THIS PRESENTS A SAFTEY THREAT IF I SHOULD HAVE MY FOOT SLIP OFF THE CLUTCH OR HAVE A CABLE FAILURE BECAUSE THE CAR WILL LURCH FORWARD BEFORE THE ENGINE DIES. THIS COULD CAUSE AN ACCIDENT INVOLVING A PEDESTRIAN OR TRAFFIC GOING THE OTHER DIRECTION AT AN INTERSECTION.

EXHAUST MANIFOLD CRACKED, CAUSING VEHICLE TO STALL. EXHAUST ODOR COMING THROUGH FRONT OF CAR. *AK