7.3 no start

DEEZUZ

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I'm not reading all this bull****.


While cranking, are you able to audibly hear the injectors clacking?
 

lincolnlocker

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Being that those oils used turn to sh!t after about 1000 miles is what worries me. I have read many oil analysis and have personal experience with said oils on many 7.3s...

but again, need more info from scanner....

live life full throttle
 

Denver

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This morning I got in the truck and it fired right up just like normal. Mid 60's temps and waited till the WTS went off. Cranked for a second and fired. No smoke, no lope, no coughing, and just smooth like its already at operating temp.

I didn't have any type of charger on the batteries over night and they were hooked up to the truck.

I did have the volt meter on the driver side battery and it showed 12.5 volts key off engine off. Key on engine off it's 11.5 volts now. Waited for the WTS light to turn off and went to high 10's while cranking. I did also again, have the key on engine off and it was 11.5 and waited a minute it came back up to 12.5.

It seems I have something somewhere causing an intermitted current draw with key on. I think when it is drawing power, it's drawing to much to have the IDM come alive. When it's not drawing power the IDM is able to come alive. Could a short in the valve cover harness cause a large power draw. I did spray the top of the engine, when it was cold, with simple green then hosed it off, before this problem started. I would say glow plugs but I did swap in a bad, non functioning GPCM and there was still a current draw. I don't know for sure though if a GPCM is bad, if it still pulls power or not.

I'm going to pull the batteries and take them to NAPA to get load tested. I'll report back my findings.

I do want to note the reason I am giving the ambient temps is not for the sake of the engine but for the batteries.
 

Addicted4

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After it’s been started for the day does it have issues restarting? Anytime you turn the key on your powering up the pcm, vacuum pump, idm, fuel pump, etc.. so your going to have less than 12 volts. What are volts while running?
 

Denver

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I took the batteries out and had them tested at Napa. They failed. 1 year old motorcrafts. 850cca. Napa testing device showed one was only producing low 500's cca at 12.4 volts and the other was high 400's cca at 12.3 volts. Ended up getting new Napa batteries as the Fords were a warranty set and the prorate would probably be little by now.

Installed the Napa ones and it started right up. Key off was showing 12.6 volts. Key on 12.1 volts. Key on starting it went to 11.3 volts. Charging volts is 14.46 within a minute, maybe 20 - 30 seconds after start. Haven't driven the truck yet but have a battery tender on them topping off the voltage.

I'll see if replacing the batteries fixes this intermittent no start issue. I'll report back over time. This was a first though for finding out the batteries were bad. Usually it's just been a slow crank right away or they are just dead. This one threw me off as it turned over strong, for about 20 - 30 seconds though and then it got slow. They were also a year old. I've had some batteries go dead in a year but was usually only one of the two, instead of both.
 

Denver

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Hows the big power wire that's behind driver battery that's right atop the fender well? See if it's clean

It looks good and is tight on the stud at the battery. I was taking a strong look at it. There is a connection right behind the airbox on the fender liner I was thinking of messing with. Is it some type of breaker or fusible link?
 

DEEZUZ

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No that's the cab /fusebox power feed connection. I wanted to make sure he's good. Very intermittent issues there
 

DEEZUZ

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I'd back probe all powers at IDM PCM while cranking and see what's getting good power
 

DEEZUZ

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Or send them both to Johnathon so he can test them both on the bench. It really does clear up potential issues with them and eliminates alot of guess work and dio
 

m j

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it is always interesting to see people immediately jump to blaming the items that they have no idea how they work. it is always the 'PCM or IDM must be bad'.
get and android with torquepro and you can see exactly what the pcm is up to.
 

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