GM Service Manual Online
For 1990-2009 cars only

EXCESSIVE ALCOHOL IN FUEL POOR DRIVEABILITY

APPLICATION CERTAIN DRIVEABILITY CONDITIONS SUCH AS REDUCED PERFORMANCE NO START, ETC. MAY BE CAUSED BY AN EXCESSIVE AMOUNT OF ALCOHOL-IN-FUEL. THE CONDITIONS MAY BE DUE TO FUEL SYSTEM CORROSION AND SUBSEQUENT FUEL FILTER PLUGGING, DETERIORATION OF RUBBER COMPONENTS SUCH AS THE ACCELERATOR PUMPS AND/OR AIR-FUEL MIXTURE LEANING EFFECTS. VARIOUS TYPES AND CONCENTRATIONS OF ALCOHOLS ARE USED IN COMMERCIAL GASOLINE. SOME ALCOHOLS ARE MORE DETRIMENTAL TO FUEL SYSTEM COMPONENTS THAN OTHERS. IF AN EXCESSIVE AMOUNT OF ALCOHOL IN THE FUEL IS SUSPECTED AS THE CAUSE OF A DRIVEABILITY CONDITION, THE PROCEDURE AS OUTLINED IN THIS BULLETIN MAY BE USED TO DETECT ALCOHOL IN THE FUEL. IN THIS PROCEDURE, WATER IS USED TO EXTRACT THE ALCOHOL FROM THE FUEL. HOWEVER, THIS PROCEDURE WILL NOT IDENTIFY THE TYPE OF ALCOHOL IE. MENTANOL VS. ETHANOL. THE FUEL SAMPLE SHOULD REPRESENT THE FUEL IN THE BOTTOM PART OF THE TANK SO THAT ANY WATER IF ALREADY PRESENT CAN BE DETECTED. A FUEL SAMPLE CAN BE OBTAINED FROM THE VEHICLE USING THE FUEL RETURN LINE OR A SIPHON HOSE. IF THE FUEL RETURN LINE IS USED, DISCARD ENOUGH FUEL TO ENSURE A REPRESENTATIVE SAMPLE FROM THE BOTTOM PART OF THE TANK. THE SAMPLE SHOULD BE BRIGHT AND CLEAR. IF THE SAMPLE APPEARS CLOUDY OR CONTAMINATED WITH WATER AS INDICATED BY A WATER LEVER IN THE BOTTOM PART OF THE SAMPLE, THIS PROCEDURE SHOULD NOT BE USED. THE FUEL SYSTEM SHOULD THEN BE CLEANED IF CONTAMINATION IS EVIDENT. SERVICE PROCEDURE: 1. USING A 100 ML CYLINDER WITH 1 ML GRADUATION MARKS (SUGGESTED PART KIMPLE #20039), FILL WITH FUEL TO THE 90 ML MARK. 2. ADD 10 ML OF WATER TO BRING THE TOTAL FLUID VOLUME TO 100 ML AND INSTALL A STOPPER (FIG. 1). 3. SHAKE VIGOROUSLY FOR 10 TO 15 SECONDS. 4. CAREFULLY LOOSEN STOPPER TO RELEASE PRESSURE. 5. CLOSE THE STOPPER AND SHAKE VIGOROUSLY AGAIN FOR 10 TO 15 SECONDS. 6. CAREFULLY LOOSEN STOPPER TO RELEASE PRESSURE. 7. PUT THE GRADUATED CYLINDER ON A LEVEL SURFACE FOR APPROXIMATELY 5 MINUTES TO ALLOW ADEQUATE LIQUID SEPARATION. IF ALCOHOL IS PRESENT IN THE FUEL, THE VOLUME OF THE LOWER LAYER, WHICH WOULD NOW CONTAIN ALCOHOL AND WATER WILL BE GREATER THAN 10 ML. FOR EXAMPLE, IF THE VOLUME OF THE LOWER LAYER IS INCREASED TO 15 ML (FIG. 2), IT WOULD INDICATE AT LEAST 5 PERCENT ALCOHOL IN FUEL. THE ACTUAL AMOUNT OF ALCOHOL MAY BE SOMEWHAT GREATER BECAUSE THIS PROCEDURE DOES NOT EXTRACT ALL OF THE ALCOHOL FROM THE FUEL. ONE SOURCE THAT THE 100 ML CYLINDER IS AVAILABLE FROM IS: SARGENT - WELCH S-24747 CYLINDERS - SINGLE GRADUATED, S STOPPER, KIMAX (KIMBLE NO. 20039). GRADUATED AND PROVIDED WITH S STOPPER CLOSURE. WITH HEAVY MOLDED HEXAGONAL BASE. CALIBRATED TO CONTAIN AT 20 DEGREE C. FOR REPLACEMENT STOPPERS, SEE S-77416. CAP SUBDIV, S STOPPER CAT. NO. ML ML NO PRICE/PKG OF PRICE/CASE OF S-24747-B 10 0.2 13 14.55 2 142.82 24 S-24747-C 25 0.5 13 17.99 2 132.39 18 S-24747-D 50 1 16 22.58 2 110.81 12 S-24747-E 100 1 22 25.96 2 84.93 8 S-24747-G 250 2 27 34.02 2 111.28 8 S-24747-H 500 5 32 21.97 1 107.76 6 S-24747-J 1000 10 32 30.80 1 100.74 4 S-24747-K 2000 20 38 45.93 1 75.12 2 SKOKIE, ILLINOIS 60077 7300 NORTH LINDER AVENUE P.O. BOX 1026 TELEPHONE - SKOKIE - (312) 677-0600 TELEPHONE - CHICAGO - (312) 267-5300 TWX - 910-223-4541 TELEX - 72-4442

ANAHEIM, CALIFORNIA 92803 1617 EAST BALL ROAD TELEPHONE - (714) 772-3550 TELEPHONE - L.A. - (213) 860-8584 TELEX - 65-5425

BIRMINGHAM, ALABAMA 35202 3125 7TH AVENUE NORTH P.O. BOX 10404 TELEPHONE - (205) 251-5125 TELEX - 5-9711

BATON ROUGE, LOUISIANA 70767 1550 COMMERCIAL DRIVE, PORT ALLEN P.O. BOX 798 TELEPHONE - (504) 344-1335

CINCINNATI, OHIO 45215 10400 TACONIC TERRACE TELEPHONE - (513) 771-3850 TELEX - 21-4459

CLEVELAND, OHIO 44125 9520 MIDWEST AVENUE GARFIELD HEIGHTS TELEPHONE - (216) 587-3300 TELEX - 98-5319

DALLAS, TEXAS 75235 5915 PEELER STREET P.O. BOX 35445 TELEPHONE - (214) 357-9381 TELEX - 7-3328

DENVER, COLORADO 80207 4040 DAHLIA STREET P.O. BOX 7196 TELEPHONE - (303) 399-8220 TELEX - 4-5535

DETROIT, MICHIGAN 48204 27501 SCHOOLCRAFT LIVONIA, MI 48150 TELEPHONE - (313) 425-9400

SPRINGFIELD, NEW JERSEY 07081 35 STERN AVENUE TELEPHONE - (201) 376-7050 TELEPHONE - N.Y.C. - (212) 349-3454 TELEX - 13-8448

WASHINGTON, D.C. 20760 (SALES-SERVICE CENTER) 8709 GROVEMONT CIRCLE GAITHERSBURG, MARYLAND TELEPHONE - (301) 948-1162

SARGENT-WELCH SCIENTIFIC OF CANADA, LTD.

TORONTO, ONTARIO, CANADA 285 GARYRAY DRIVE WESTON, ONTARIO M9L 1P3 TELEPHONE - (416) 741-5210 TELEX - 06-527129

MONTREAL, QUEBEC, CANADA (SALES-SERVICE CENTER) 3300 BOULEVARD CAVENDISH, MONTREAL, P.Q. H4B 2M8 TELEPHONE - (514) 481-0119 TELEX - 055-66396

INTERNATIONAL DIVISION

7300 NORTH LINDER AVENUE P.O. BOX 1026 SKOKIE, ILLINOIS 60077 U.S.A. TELEPHONE - (312) 677-0600 CABLE - SARWELSCI TWX - 910-223-4541 TELEX - 72-4442

General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.