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93 4.0 crank but no start. Help

flagdad

NAXJA Forum User
Location
Arizona
Hey guys, I’ve been trying to get my 93 to start for a couple of weeks. It’s getting up there in age so I decided to throw parts at it: cps, tps, fuel pump. Still cranks but no start. I’ve got spark and good fuel pressure to the rail. I’ve tried spraying starting fluid into the throttle body but no change. I’m thinking I may need a new pcm but obviously I’m tired of throwing parts at it. Are there other sensors or relays that could prevent starting? Btw, if I get a rebuilt pcm will it need to be flashed or can I just plug and play? Thanks in advance. I have searched and read tons of forums but can’t figure it out. New to all of this.
 
Btw, I’ve read about the nss; other than wiggling the selector in park and neutral is there a good way to check this?
 
Btw, I’ve read about the nss; other than wiggling the selector in park and neutral is there a good way to check this?

Make sure your parking brake is on or chock the wheels (or better yet- both) and put the transmission in reverse. If your neutral safety switch is good, you SHOULD see your reverse lights come on.
 
A faulty NSS will prevent it from cranking.
 
When was the last time it ran? Did you do any other work to it?
 
Did you try a NOID light on the injectors?

Edit: about 2 threads down, its basically, the same issue. On the NOID light, I think a set cost $40-60. You just need one out of the set. On mine XJ, it flashed as I released the key. NOt while cranking. A friend suggested replacing the electronic ignition switch. So, $50 at NAPA, some starting fluid, and a few tries. Then it ran fine.
 
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From my limited knowledge a faulty nss means no crank.... If it's cranking then I would look elsewhere. Are all the fuses good? No broken grounds? Agree with above mention of checking injector pulse with niod.

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Well, If anyone ever stumbles across this post I will let ya'll know what I went through and maybe you will learn from my mistakes. After 3 weeks of no start (had fuel & spark) and throwing parts (cps, tps, map sensor, plugs & wires, fuel pump, filter, computer) at it, I opened up the distributor and immediately saw the problem. The little spinner in the distributor was broken. Apparently it was still sparking, but not enough to start. I replaced that ($5) and immediately cranked right up. It ran for 10 minutes in the driveway and then I took it for a ride. 2 miles later she died and stayed dead. I didn't have any fuel pressure and seeing as how I just put a new bosch pump in it, I assumed I had an electrical gremlin. I tested wires for a week and couldn't find an issue so today I ran a wire directly to the pump and she was dead. I still had the old pump so I threw that in and she fired right up. I'm really happy to have her running, but GD!
 
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