I have a 1994 Isuzu Rodeo SUV w/233k miles. Difficult to start since may 2008. Engine cranks for 8-10 seconds before sputtering to life. When accelerator depressed, sputtering, black smoke, then eventually smooths out. All preven. maint.(minor/major) done since 1994 includ. fuel filter in may when problem started. Trucks runs great, engine smooth and strong. No smoke in exhaust when running. If truck sits longer than 15 mins. have problem starting. Dealer cleaned throttle body and replaced Idle speed control valve. No change. Actually made situation worse. Takes longer to start. No black smoke anymore but strong fuel smell from tail pipe after start. Friends suggest: Fuel Injectors(original) not holding pressure therefore flooding cylinders, Ignition coil(original)not providing spark, Fuel pump sender(original), even suggest release gas cap pressure after useage. Please help, broke and can’t afford to replace parts at will.
I think your friends are right about the fuel injectors. They were my first thought when I read the symptoms. If you want to verify this, you could attach a fuel pressure gage to the pump, start the engine up then shut it down and watch the pressure drop, and then pull the plugs and see if you have wet plugs. I’m guessing the injectors are spraying off the line pressure when they’re deenergized and supposed to be closed.
Thanks for the quick response. Kind of had a feeling the injectors might be shot. I’ll forward your suggestions to my mechanic. This is out of my league. I’ll keep you posted.
I consider myself a pretty handy guy/intermediate weekend warrior. My question’s are: how hard is it to replace the injectors myself? The intake manifold has to come off right? It seems that the injectors screw in like a spark plug. How much are injectors? How much should I expect to pay on side job. Dealer labor rate is around $100.00/hr. Can this job be completed in an 8hr. shift? Am I biting off more than I can chew?
In addition to a leaking injector, consider that the fuel pressure regulator might be leaking fuel into the intake manifold. A quick check of the regulator is to pull the vacuum hose going from the regulator to the intake plenum and see if there is raw gasoline inside. Replacing the regulator is a lot less expensive and takes less time than replacing an injector.
Hope the regulator is what it is.
Thanks for the tip. I just ordered a single injector from a parts whse. in Cincinatti. Should be in my hands by 6:00PM tomorrow. Saturday I’ll be pulling the fuel rail apart, pressurizing the system and visually inspecting the injectors. I hope it’s only one injector and not all six. $130.00each. I’ll let you know on Monday how I made out. Going to also inspect the FPR while I’m there. Thanks again.