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grid heater and oil pressure

1668 Views 33 Replies 6 Participants Last post by  NCC74656
is 81psi at cold idle to high? my truck starts there and falls to 38psi at idle when warm.

its gotten a bit chilly here and ive started to notice it a bit harder to crank and more white smoke. my "wait to start" light has not come on yet. what type of diagnostic can i do to test this with out needing to make the engine colder?

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the alt has no ripple its a few months old. the volume of the system does impact how the batteries charge as the truck takes about 5 turns of the flexplate to start durring cranking (im pretty sure there is a small air leak in the fuel system by the pump that is allowing the fuel to back drain as i can bump the starter and let the pump run a bit and it starts faster). my short 4 mile drive to work is not enough time to allow the alt to charge the batteries back up after that draw. the radio pulls about 350A at full tilt, the alternator puts out about 405A at full tilt so its pretty close.

ill report back in about an hour on the WTS light as im about to leave for work.
the voltage gauge started at 13 and stayed there, i never saw it drop or go back up. HOWEVER after letting it sit for 20 seconds and THEN starting it fired up instantly. i do not know if its a fluke or if the heater is actually working??? now i have NEVER seen these batteries drop like you say they will, my understanding is the heater core only pulls like 300A right? so thats a very small load to make them go from 13 to 8.
That may not be an air/fuel problem. Do the wait to start test I posted above.
300 amps is a HUGE load and you will see a drop even with good batteries and good alternator, it might not be to 8v but mine will drop to 11-11.5 while cycling. From outside it almost sounds like the AC compressor is turning on and off
300A does not seem very much, i can use my winch and not have more than a 0.4V drop over a 15 min period and it pulls a good deal over 300A. i have 4 group 49 AGM's from sears (diehard platinum), they are rated at 850CCA each and an alternator that puts out 290A at idle.

i did the test this morning, i noticed no voltage drop but it started easier as if the grid heater was working. there was no WTS light. maybe i should get a clamp meeter and check for current draw when i turn the key forward?
300 amps is a lot but a 290 amp alternator isn't get near the drop that the stock alternator would obviously.

You could use a clamp ammeter but most will only measure AC current not DC or if you don't have one just check the voltage across the grid heater to see if the relays are coming on, more than likely the element itself is fine, if you get voltage and no heat I would either get a clamp meter and measure the current or measure the resistance if the element. It should be pretty low. If you don't get any voltage at the element it self check the voltage on the coil side of the relay coming from the ECM
ill do that tomorrow. im currently in the middle of installing a remote starter/alarm and its turning into a VERY long project.

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im still working on that remote starter install and i came across 4 cut wires in a harness above the white box with bolt in plug to the left of the steering column. anyone know what the wires coming from the top of that box go to? the front 4 wires were cut.
Nobody has any idea what may have been under there and cut out. Probably something aftermarket.
You should just pay a Viper installer to do it for you.
shop labor rates would be 4200.00 (ish) for this install

i am a viper installer, i won all that product at the local training we had a couple days ago in the raffle. so far its a pretty sweet system

the wires were not aftermarket, they were part of the factory harness and in the main wiring harness to the engine bay. a black/orange wire, brown/blue, brown, and a yellow/violet.
Is there a blue trailer brake harness plug there near the steering column? If not, somebody probably cut it out and left those wires. Find a schematic on here or Google and they will tell you what those colors go to. If you are a Viper installer how could that install be a $4200 install. Was that typo? That would be 20 to 50 hours. I do not think so, it should take no more than 2-4 hours for anybody that has done a Dodge truck before.
no trailer harness plug. the wiring that was cut was VERY tight up in there. it is most certainly factory and is coming out of the top of the junction box that has a plug held in with a bolt on its face, to the left of the steering column under the dash. this wiring goes thorugh the fire wall and into the distro box of fuses under the hood. it looks to me like someone had something tied or wrapped around this large factory harness and in the process of cutting it off they snipped these wires. the wires are all next to one another. i have not tested voltage on these wires but perhaps i will, im getting more curious as to wtf they were for. the FSM shows the plug i speak of but goes into no further detail im afraid.

at shop rates the install would be as follows, yes that 4200 was a typo.

5706- 499.99
vsm 250 - 350.00
relays X6- 179.94
451m - 39.99
508D - 129.99
516L - 199.99
506M - 59.99
diodeiso - 49.99
504D - 29.99
shop - 7.79

the following is labor

removal of old system - 69.99
tach hook up - 29.99
factory alarm disarm - 29.99
radar sensor - 79.99
8ga power run - 99.99
window hook up - 149.99
defrost hook up - 75.00
wiper hook up - 125.99
aditional siren wiringX12 - 179.94
winch hook up - 99.99
clean up of current wiring - 95.00/hour
rear tool box sensor - 39.99
passenger door - 75.00

total of 2711.51
189.80 of tax
for a grand total of $2900.51
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It likely was to the tlr brake plug.

I can't imagine rewiring the whole truck to install an alarm and remote start. Sounds a lot like dealer way over packed labor rates. I bet you do not get many of those jobs. 11 hours to install?
i was in the shop over night and im still not done. the main reason it is taking so long is when i bought this truck a couple years ago i was mostly mechanical. i had to replace the entire dash and swap it from another dodge ram. now that i have been working in electrical at my shop i have learned more in this last year than i had known my entire life. thus i am unfu**ing a good deal of the wiring inside the dash area that i had to repair from the previous owner and i attempted to repair when i bought the truck.

aside from that our shop rates are 95.00 an hour, the average remote starter is around 750.00 installed for newer vehicles and around the 500.00 range for older ones.
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