Engine Performance problem
1996 Chevy Blazer 6 cyl Four Wheel Drive Automatic 200000 miles
I have a 96 Chev Blazer. I have replaced the fuel injector spiders 4 times in the last year and a half. When I put a new or tested used into truck it runs great for 2 to 8 months and then fails again. I have checked the fuel tank and fuel return line they look fine. What could be causing the fuel injector solenoid to fail? I do not receive any ODBii codes.
Is it the same injector(s) all the time or a specific one? Also, I'm not sure what you mean by " spiders". And, are the injectors plugged or the coils burned out Please advise.
December, 10, 2008 AT 6:48 PM
Gas goes to a single solenoid and then goes to six lines that go to injectors (it looks like a spider.)
December, 10, 2008 AT 7:39 PM
I've only heard that term used on diesels, now I know. Anyway, you didn't give me the info on the the injector(s). Please advise.
December, 10, 2008 AT 8:17 PM
The gas goes from fuel pump to the fuel injector / fuel regulator which has a solenoid on the assembly (spider) which is failing. The resistance on the solenoid goes from about 1.5 ohms to 30,000 ohms. The fuel injector nozzles check out fine.
December, 10, 2008 AT 11:07 PM
This may sound like a stupid question, but how can the resistance go from 1.5 ohms to 30,000? I have pondered over several diagrams and what you seem to be testing is a fuel pump/oil pressure cutout switch. How many wires go to this unit? If my diagram is correct, this switch will shut off the fuel if oil pressure drops beyond a certain point.
December, 11, 2008 AT 9:31 AM
I am not testing fuel pump, the spider is isolated from electric circuit when it is tested with an ohm meter.
Back to the original point, what can be making the solenoid on the the spider fail. There is no restrictions on the fuel flow and the fuel pressure is at 60psi, so it must be in the electrical circuit. I'm not sure where to start looking. A dealer tried replacing the computer but that made no difference.
December, 11, 2008 AT 10:07 PM
Have you checked to voltage and grounds going to the spider? You may have a bad harness.
Check the harness for any worn through insulation as well. Because the system actually uses ground switching a grounded wire could be causing high current, also shorting out the coils
Also, where have you been buying the replacements?
December, 11, 2008 AT 10:32 PM
Thanks SWilliams for the direction. I will investigate.