No fuel injector Pulse

It sounds like lost the ASD relay so the computer is not getting power. Here is a guide and some diagrams (below) so you can get the problem fixed.

https://www.2carpros.com/articles/how-to-check-an-electrical-relay-and-wiring-control-circuit

and

https://www.2carpros.com/articles/how-to-check-a-car-fuse

Please run some tests and get back to us so we can keep helping you.

Cheers, Ken

The pump may have failed. Check for power back at the pump to verify

Roy

Check the ASD relay it powers both fuel/spark.

Check the ASD relay it powers both fuel/spark.[/Quote:64ceab88f5]

. Was able to attain fuel pressure of 46 psi by jumping fuel pump relay. Terminals 85-86.87-30. But still no spark to plugs. Any suggestions?

When you turn key to On do you hear the fuel pump for a few secs?

Turn key On Look for power at coil positive terminal-do you have it, if so check the crankshaft position sensor at left side of tranny. Inspect it

No power at coil check 20amp fuse in power distribution box. And inspect also the fuel pump relay and ASD relay. When you turn key On this relays should click- The computer energizes both relays.

The Cam sensor is in the distributor.

From: rasmataz
To: wolfredrunning
Posted: Mon Aug 27, 2007 4:13 am
Subject: Re: 1996 jeep cherokee no start
Find the PCM at A2 pin out when key is On is should have battery voltage. If not the PCM is gone.

A2 also supplies the relays power, not there, the relays will not transfer power to coil / pump/injectors thru wire at ASD dark green/orange and F/P relay dark green/white.

Good Luck

_________________
Be patient you're not the only one that needs our help. So hang On. We'll get to you. Am the only female moderator in here so give me a break.

Hi rick a and welcome to 2carpros

Test the ignition switch and the ASD relay-The ASD relay powers the coil/fuel pump relay/fuel pump/injectors

Check for power at the injector harness dark green and orange wire and tell me if you have it-

Do you hear the fuel pump come On when key at run position-if not you have a power problem -If so do a fuel pressure check-no pressure or not within specs replace the pump.

Get a noid lite from the parts store hook it up to the injector/s harness and crank engine over is it flashing?

You are further along than most people would get, but you need to understand how the system works.

The ASD relay feeds the ignition coils, injectors, and fuel pump or pump relay. The ASD relay is turned on by the Engine Computer for one second when you turn on the ignition switch, then again during engine rotation, (cranking or running). No spark causes about two percent of crank / no-starts. No fuel pressure causes about three percent of crank / no-starts. Ninety five percent of those failures are caused by loss of spark and fuel pressure.

The first clue is you still should have some fuel pressure from that one-second burst when you turn on the ignition switch. That is why fuel pressure isn't a good clue for no-starts.

The place to start is by checking if the ASD relay is turning on during cranking. The easiest way to do that is to watch the voltage at the ignition coil or any injector. I am not sure of the wire color, but you will find the same color wire at every injector and for one of the coil wires. On most vehicles that is a dark green/orange wire, but yours might be different. Use a test light for this because most digital voltmeters do not respond fast enough. Back-probe one of those wires. You should see the test light turn on full brightness for one second when you turn on the ignition switch, then again when you crank the engine. Let me know what you find.

Have you read the diagnostic fault codes?

At the dark green and orange wire at the injector harness stick a test light to it do you have power?

No power to coil/injectors/fuel pump and ASD relay okay points to the computer-see below diagram