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GDibs, ASE Certified Technician
Category: Car
Satisfied Customers: 7
Experience:  ASE Certified Master and L1 Technician
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I have a 1997 Isuzu Rodeo V6 and have a no start, no

Customer Question

I have a 1997 Isuzu Rodeo V6 and have a no start, no injector pulse condition. I have replaced both the crank and cam sensors, also tried a different PCM. engine runs if i spray fuel into the intake.
Submitted: 10 months ago.
Category: Car
Expert:  GDibs replied 10 months ago.

Do you have a way to check for codes? and if so are there any codes? When was the last time this engine ran? Did it die while driving or after other repairs were made? How did you determine it has no injector pulse? Do the injectors have battery voltage supplied to them?

Customer: replied 10 months ago.
engine ran following timing belt change, no codes, died while driving according to previous owner, injector pulse checked with noid light, battery voltage present at injectors. I am a certificated aircraft mechanic with 30yrs exp and 10 yrs automotive exp prior to computerized fuel injection.
Customer: replied 10 months ago.
Also fuel pressure on fuel rail is 47psi
Expert:  GDibs replied 10 months ago.

It sounds like you are able to hook a scanner up to this and read dat. Does it have a RPM reading during cranking? For this system to have injector pulse the PCM needs to receive a signal from the ignition module. Are you equipped and familiar with testing square wave signals?

Expert:  GDibs replied 10 months ago.

The signal wire from the ignition module to the Engine Computer is the yellow/red wire. The ignition module should have a good crankshaft position sensor signal based on the fact that you have spark. One thing to keep in mind is that the ignition module is stand alone, you could unplug the engine computer and still have spark.

Expert:  GDibs replied 10 months ago.

I was an Isuzu Master Technician. I used to work on these things when they were new. Used to find lots of loose grounds on the intake manifold after people had worked on these things. The ECM gets its ground there. A bad ECM ground could cause your type of problem.

Expert:  GDibs replied 10 months ago.

I hope this was helpful information and led you to fixing your problem. Thanks

Customer: replied 10 months ago.
do you have any other suggestions, all the grounds i have found are now clean and tight to no avail, do you know where i can get an accurate wiring diagram for this year, the one i have is for 98/99 and the color codes for the wires don't match the car
Expert:  GDibs replied 10 months ago.

Ok , I just realized that the Diagrams the Motor provide for this year were incorrect. This year does not have an ignition module and coil packs and also doesn't utilize the signal from the ignition module. I am now wondering if the injectors have good voltage supply to them. A test would be to find the injector wires at the PCM and see if when you tap the to ground, if the injectors actually click and cause a drop in fuel pressure. I have wiring diagrams but not sure best method to get them to you.

Expert:  GDibs replied 10 months ago.

this is the one with the injector circuits

Expert:  GDibs replied 10 months ago.

here is another useful one. see if you have a 5 v reference to the cam and crank sensor and the Throttle position sensor.

Customer: replied 10 months ago.
Thx for the diagrams. they match the car and make a hole lot more sense than the ones i've been trying to deal with. now that i know where to pick the signal i can better chase the problem.
Expert:  GDibs replied 10 months ago.

Let me know if need any thing else

Expert:  GDibs replied 10 months ago.

Hope you got something figured out on your Rodeo and got it up and running.


Expert:  GDibs replied 9 months ago.

its been awhile and I never heard whether you got your rodeo running or not.

Expert:  GDibs replied 7 months ago.

any reply