I consider myself a pretty handy guy/intermediate weekend warrior. My questions are: how hard is it to replace fuel injectors on a 1994 Isuzu Rodeo LS V6 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?
The injectors just slip into the intake manifold and the fuel logs. The ends are sealed with O-rings. Each injector costs $60-100 but check with the dealer parts desk or independent parts store. You will need new O-rings - 6 for the vacuum side and 6 for the fuel log side. Remember to release the fuel pressure safely so you don’t spray fuel all over causing a fire risk.
Hope that helps.
Do you have a service manual? I have one that covers your car and just reading over the procedure I don’t see anything that should be too difficult if you’re systematic about it. The two things you really need to be careful about is cleaning the gasket surface on the plenum and torquing the bolts correctly so you don’t get any leaks. You’ll also want to be sure to keep all the vacuum hoses you’ll have to disconnect straight. Not to gloat, but the procedure for removing the injectors on my 92 Rodeo with the GM TBI engine is basically “depressurize fuel system, remove air filter. remove fuel injector”. I suppose the added complexity is just the price you pay for the extra horsepower you get with the multi-point engine.
You could also just try cleaning the injectors. The “fuel system flush” is one of those high-profit items some shops love to sell to EVERYONE even though the vast majority of people don’t need it, but you might be the odd one who does. A fuel injector is basically a solenoid valve which is basically metal plug that lifts up when the computer energizes the electromagnet. In the case of a problem like yours where the injectors are leaking, the problem is very often that some junk has worked it’s way up to one of the injectors and is holding it open a little. If this is the case, it could also only be one of the injectors that’s doing it, so pulling the plugs and seeing if one cylinder appears sootier that the others might give you a clue. Though at this mileage, they could also just be worn-out, which can also cause leaking.
Thanks for the tips. 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.