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720 Views 7 Replies 4 Participants Last post by  Conxds
Well my 98.5 is being a pain again

just did yet another VP and it seems that I now have an air leak (long start)

likely from a quick connect on the AD165 did the 5 gallon bucket test with the

same results and can actually hear air somewhere

ontop of that stuck 2 new 27 series deka batteries in it and its cranks slow

and when it lights off im reading 11.2 ECM voltage for roughly 45 seconds

with the voltage this low it also causes LP pressure to be at 14 psi rather
then 18

2 thoughts (and im looking for insight)

bad alternator or bad starter I replaced alternator 3 years back never have

done thestarter maybe worn out and drawing to many amps?
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Voltage is only low during cranking?
You don't want a lot of fuel pressure(actually 0psi is fine) when starting. Once running, you want over 14psi at all times.
How do your connections on the battery, alternator, and starter look?
The ECM regulates voltage, so there could be an issue there too. I believe either the crank or cam sensor tell the ECM to charge the batteries?
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As for the fuel leak/hard starting. check the fuel return line o-rings on the back of the head. had a buddys truck do this and it leaked there.
and from everything else ive learned about 24v's check check check and then triple check all your grounds again. Hope this helps some
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Thanks for the replays check all wires and grounds and starter is now out voltage is low while cranking and 45 seconds after running then stays over 13 volts fuel pressure comes up and goes too 0 while wait to start light is on once fired and voltage is low fuel pressure is low then returns to normal when voltage does replacing starter tomorrow we shall see
I think what you are experiencing with the low voltage is the grid heater cycling shortly after startup. This will cause the voltage to read a little low, the lights to dim and the fuel pressure to read low because the grid heater draws so much power from the truck. It is very common and not bad for the truck. This will cycle until the truck gets above about 18mph.

As for the air leak, that is just something you will need to figure out and fix. The long start could be because of cold but you said you replaced the batteries and it still cranks slow. By this do you mean that the starter still sounds weak or do you mean that the starter sounds strong but the truck doesn't crank over right away?
I understand about the grid heater but a grid heater would be worthless if it damn near killed your batteries on start up lol

swapped out the starter got lucky and they had one on the shelf at autozone for 190 out the door with a lifetime warranty

huge difference truck cranks fast and I never noticed how loud the old one was!

still have a nasty air leak im royally annoyed with this quick connect setup just haven't had the time to drop the tank :banghead:
Do you have enough hose length to cut off the quick connects and replace them with push locks?
Luckily I do hoping to get tank dropped today been going back and fourth on

Doing push lok or just going AN
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