98 crank no start

[Cparks93]

So my daily finally left me stranded. For starters my WTS has always been sluggish to come on when starting the truck. It would not start until WTS light came on. Would crank and crank unless I waited for light. I figured it was a good habit anyways. 

On my way to work Saturday I noticed my headlights were dimming on and off, pretty abnormal because ambient temp was mid 40s and truck started like normal. 

After getting to work, I drove the truck 5 to 6 times to get tools with no problems at all. Finally getting geared up to go home, wait for WTS, light comes on, so I crank and get nothing. Now have no WTS and no start. Fuel pressure is at 18lbs. 

Code reader pulled 4 codes 

p0500

P1693

p1492

And one more I cannot remember off the top of my head. I will rescan it tomorrow. 

Anyone have any insight? 

[GSX455]

Look up the battery temp sensor under P 1492, see below for post; are the batteries good and the ground connections  good?

 

p1693 is just saying you threw a code, good luck

[Cparks93]

Thank you, I will try this tomorrow 

 

So the battery temp sensor will cause a no start??

[dripley]

With the wait to start light wacking out, it could be a bit deeper, like maybe the ECM, weak battaries or starter.

[Cparks93]

I was hoping no one said ecm

batteries are topped off and it turns over great... just won’t fire..

[dripley]

Is the WTS lit when you try to start it??

[Cparks93]

It used to, now I’m not getting a WTS at all. I let it sit all night and it came on, but still would not fire. 

[Mopar1973Man]

Wait to start lag is a bit off a problem pointing to ECM failure.

 

As for lack of start is there lost of prime? Will the truck start if parked nose down? What is your cranking fuel pressure? (7-12 PSI).

[Cparks93]

Yes, it will loose prime.. but I do keep it nose down, at least until I fix that issue.

Fuel pressure is above 12psi when cranking. But that is pre vp

 

Will the ecm failure cause a no start? Because I am getting fuel to the vp, but I haven’t checked for fuel at the injectors. 

 

Forgot to mention all battery connections are clean as well..

[dripley]

While you are getting fuel to the VP if the ECM is not turning the VP on, so to speak, it will not start. Crack some of the injectors open and you can see if any fuel is getting there.

[Dieselfuture]

So more than likely you have a bad alternator that's producing excessive AC current and that's what is frying your electronics. So when you repair your ECM make sure you have minimun AC current, like 0.03 vac or less. Don't just go and buy a junk reman from parts store and if you do make sure you test it right a way. They don't really test for AC current at part stores, and you'll need a good voltmeter not a cheap one, cheap one will show you 30 vac 

Also do a ground mod, there is an article here on how to. That will reduce your AC noise also and just help all together with wiring. There is also an ecm rebuilder list somewhere here to.

The truck will not start unless that wait to start light lights up first, or if you hotwire vp.

Edited October 29, 2018 by Dieselfuture
Spelling

[Cparks93]

Okay thank you all, I’m going to do some further investigation this evening when I get off work. 

[Mopar1973Man]

12 hours ago, Cparks93 said:

Fuel pressure is above 12psi when cranking.

 

Too high you need it to fall in the 7-12 PSI other than that the timing piston is forced too advanced and makes it impossible to start. Make sure your lift pump is controlled by your ECM and that the operating pressure is not too high. This is the reason I suggest 15 to 17 PSI operating pressure. This way cranking pressure is low enough to start easy.

 

2 hours ago, Dieselfuture said:

So more than likely you have a bad alternator that's producing excessive AC current and that's what is frying your electronics. So when you repair your ECM make sure you have minimun AC current, like 0.03 vac or less. Don't just go and buy a junk reman from parts store and if you do make sure you test it right a way. They don't really test for AC current at part stores, and you'll need a good voltmeter not a cheap one, cheap one will show you 30 vac 

Also do a ground mod, there is an article here on how to. That will reduce your AC noise also and just help all together with wiring. There is also an ecm rebuilder list somewhere here to.

The truck will not start unless that wait to start light lights up first, or if you hotwire vp.