electrical issues
 

I have a 1987 jeep cherokee and it has no pulse to the injectors i have already replaced the crank sensor also no power to fuel pump

My 90 has a ceramic resistor on the fender-wall near the battery. With a meter or a test light, are you getting power there? I think the front get's full voltage and 9 (ish) goes from the other end to the pump. Everything else seems to work? It cranks, has spark? Also, It IS an inline 6 (4.0)?

cam sensor control injector pulse not crank,pg 19 herehttp://www.lunghd.com/Downloads_and_...ion_manual.pdf

You say you have no injector pulse, do you have spark?

If you do follow these steps next.....you will need a meter..(beg,borrow but dont steal) one..LOL

Verify that the power and ground are good to the (PCM) Powertrain Control Module.

Check the MAP sensor voltage and the TPS voltage at key on with the sensors plugged in. The TPS voltage should be close to .5 -1 volt. The MAP sensor voltage should be close to 4.5 volts at key on. These would be the only sensors that could cause this problem.
Potential Causes: Throttle Position Sensor (TPS)

On the Renix system, unlike the HOs, the sync generator in the dizzy will not cause the injectors to have no signal. It is in there only to tell the ECU what cylinder is coming up to fire so the injectors will fire sequentially with the firing order of the engine. If it fails, the injectors batch fire. At the dealership back in the olden days, the only way we ever noticed the sync gen was bad was when scanning with the DRB looking at the other sensors.

We need to know if you have spark or not, as suggested above, to determine which direction to go in diagnosis. If you have spark but no injector pulse, we know your CPS is good. Where did you purchase the CPS?

Whoops! The resistor is on the left near the air cleaner, not, "My 90 has a ceramic resistor on the fender-wall near the battery."

Hope I didn't mess you up too bad! :icon_redface:

Yes it jas fire of i could get someone to ride on hood and pour gas in it would run lol the motor will actually run if u do that

So you said no power to the fuel pump. I think the wire from the pump goes to the back end of that resistor I was talking about. (does on my 90). You should get battery power to the front of it. Actually looking at it just now I remembered that those connections went funky on me once. So with power there you should hear the pump run.