I have a 89 Chevy S10 Blazer with the 4
ok, I was looking at my data and wiring diagrams and was wondering if that the ignition source at the relay is not shutting off when you turn the key off ,which can be caused by a faulty ignition switch signal to the ecm which in turn goes sends a signal to the relay( to trigger the 2 second fuel pump prime)the prime signal should only be 2 seconds and then the relay should click off if it stays on and the fuel pump still runs it can be a faulty ecm to check this pull out the relay and on the relay socket check battery for power at terminal A ,then turn the key on and there should be 12 volts at terminal E , XXXXX is a ground ,D is a 2 second prime signal (ground) :When the key is first turned ON, without the engine running, the ECM will turn the fuel pump relay ON for two seconds. This builds up the fuel pressure to normal operating pressure. If the engine is not started within two seconds, the ECM will shut the fuel pump OFF and wait until ignition reference pulses are present. As soon as the engine is cranked, the ECM turns the relay ON, which powers the fuel pump. The ECM continues to power the fuel pump during engine operation. If the fuel pump relay fails, it is backed up by the oil pressure switch, which continues to operate the fuel pump as long as oil pressure remains above 28.0 kPa (4 psi). When Ipatagonia discount code0 attempt to start it it will fire once or twice but does not start. If I crank it over for about 45 seconds and stop, I can hear the fuel pump running, it runs for about two minutes even wiht the ignition off and the key rmoved. You can hear a change in tone of the pump after about a minute. Wiht the relay removed you don hear the 2 second prime but the rest stays teh same. With the fuel injectors when the key is turned on it goes to.03 volts then drops to .01 volts and stays there. When the engine is turned over it goes up to 1.68 volts. The fuel from the injectors sprpatagonia discount codeays in a cone pulses alternating between the two. The battery checks out OK, wiht a full charge it only drops to 11.4 volts when the starter is engaged (still with relay and oil pressure switch disconnected). On the relay harnes I get 13.3 volts at A nothing at E. when thew switch is turned on there is still 13.3 volts on A and nothing on E. The problem started wpatagonia men's reversible flannel jacket reviewith lpatagonia reversible flannel jacket revieweaky fuel injectors which is why I rebuilt the TBI. After the TBI was rebuilt the vehicle would not start, in tracking problems down the timing was off so I removed the timeing cover and noted that the chain had jumped a cog, put new gears and chain on. After putting the everything back together I noticed that the fuel pump continued to run after the ignition had been turned off, and the vehcile still will not start. I removed the starter tonight becuase i had noticed that the seal had moved now I need a new seal (bound in the flywheel). I will test the 2 second prime but cannot turn the engine over yet. By touching and removing a test light, connected to 12 volts, to CKT 430, a reference pulse should be generated. If injector test light blinks, the ECM and wiring are OK. This step tests for 12 volts to the injector. It will also determine if there is a short to voltage on the ECM side of the circuit. This test checks for continuity to the ECM . Chart A 5 Fuel Pump Relay Circuit Diagnosis (One Fuel Tank)Wiring Diagram For Chart A 5 Fuel Pump Relay Circuit Diagnosis (One Fuel Tank)CHART A 5 FUEL PUMP RELAY CIRCUIT DIAGNOSIS (ONE FUEL TANK)Circuit Description :When the ignition switch is turned ON , the Electronic Control Module (ECM) will turn ON the in tank fuel pump. It will remain ON as long as the engine is cranking or running, and the ECM is receiving distributor reference pulses. It is designed to over ride the ECM two second pump operation and will run the fuel pump for twenty seconds at initial ignition ON . If the pump runs, it may be a fuel pump relay circuit problem which the following step will locate. This step checks voltage from the battery and the ground circuit to the relay. This test determines if there is voltage from the ECM, terminal A1, to terminal D on patagonia outlet store minnesotathe relay connector. Check for power and ground circuit to the fuel module and a complete circuit to the pump from terminal A . This chart should be used on engines using the Model 220 throttle body. If TPS is over 2.5 volts the engine may be in the clear flood mode which will cause starting problems. If coolant sensor is below 30C, the ECM will provide fuel for this extremely cold temperature which will severely flood the engine. Voltage at the spark plug is checked using Spark Tester tool ST 125 (J26792) or equivalent. No spark indicates a basic ignition problem. While cranking engine there should be no fuel spray with injectors disconnected. Replace an injector if it sprays fuel or drips like a leaking water faucet. Use an injector test light like BT8320, or equivpatagonia discount code1alent, to test each injector circuit. A blinking light indicates the ECM is controlling the injectors. See CHART A 6. Water or foreign material in the fuel system. A gropatagonia discount code3unded CKT 423 (EST) may cause a No Start or a Start then Stall condition. Basic engine problem. This test will determine if the ignition module is generating a reference pulse, if the wiring is at fault or if the ECM is at fault. By touching and removing a test light, connected to 12 volts, to CKT 430, a reference pulse should be generated. If injector test light blipatagonia everlong review a businessnks, the ECM and wiring are OK. This step tests for 12 volts to the injector. It will also determine if there is a short to voltage on the ECM side of the circuit. It will remain ON as long as the engine is cranking or running, and the ECM is receiving distributor reference pulses. It is designed to over ride the ECM two second pump operation and will run the fuel pump for twenty seconds at initial ignition ON . If the pump runs, it may be a fuel pump relay circuit problem which the following step will locate. This step checks voltage from the battery and the ground circuit to the relay. This testpatagonia everlong review 101 determinepatagonia everlong review 380s if there is voltage from the ECM, terminal A1, to terminal D on the relay connector. Check for power and ground circuit to the fuel module and a complete circuit to the pump from terminal A . If OK, and the pump does not run for the specified 20 seconds at initial ignition ON , replace the Fuel Module. Normally, there should be battery voltage at the C and + terminals. Low voltage would indicate an open or a high resistance circuit from the distributor to the coil or ignition switch. If C term. voltage was low, but + term. voltage is 10 volts or more, circuit from C term. to ignition coil or ignition coil primary winding is open. Checks for a shorted module or grounded circuit from the ignition coil to the module. The distributor module should be turned OFF , so normapatagonia discount code2l voltage should be about 12 volts. If the modupatagonia guide jacket 5tle is turned ON , the voltapatagonia guide pants reviewsge would be low, but above 1 volt. This could cause the ignition coil to fail from excessive heat. With an open ignition coil primary winding, a small amount of voltage will leak through the module from the Bat, to the tach terminal. Checks for an open module, or circuit to it. 12 volts applied to the module P terminal should turn the module ON and the voltage should drop to about 7 9 volts. This should turn OFF the module and cause a spark. If no spark occurs, the fault is most likely in the ignition coil because most module problems would have been found before this poinpatagonia houdini jacket auctiont in the procedure.
Todd L
Rochester NY
Wonderful service, prompt, efficient, and accurate. Couldn t have asked for more. I cannot thank you enough for your help.
I couldn t be more satisfied! This is the site I will always come to when I need a second opinion.
