I6FREAK

anyone know the dimensions of a radiator core on a 99 isb with ac

Do you still need it? Dave

I have fabricated the wiring harness using a weather resistant high rush amperage(up to 150 amp) relay(1 million cycle rating). I soldered the socket clips to all wires and shrunk 2 inch teflon sleeves over the beginning of all soldered joints. I machined an anodized aluminum switch panel that I will mount on my center console(homemade). I am using 16 gauge military grade teflon shielded electrical wire and an inline 15 amp fuse from power supply(Inline fuse harness has 14 gauge wire). Any one have preferences on a location to take power from? PDC of Alternator ?? or other??Thanks

Will the ECM trip the CEL if I activate my fuel pump independent of the supply voltage from the ECM? In other words, if I leave the wiring harness that would normally plugged into the lift pump, unplugged. If so what is the safest way to complete the circuit so the ECM does not trigger a CEL?

I've have a 4x4 jeep already, but I think I will look for a 4x4 Cummins that can tow all my stuff... maybe a 5 speed but they are so rare here....when they are available they are around 12 k.... California is a joke...lol.. Thanks very much for the input.

I'm in California, but I was asking about other states, ya know the ones that actually have seasons..lol

I need some experienced advice from you guys who live in weather that often gets snow/ice . I just had a new vp in and I installed a raptor 100 running around 18 ish psi....my truck is a 2wd...before I start getting too crazy with my effort to make the truck as reliable as possible and efficient I want to make sure that 2wd will not disappoint me in the long run... I have been off roading for 20 years, but not with such a long truck without 4wd...I am itching for a stick shift... I don't care about power as I care about reliability so the raptor is the only aftermarket part on the truck that would be considered a performance mod... I consider it a necessary to keep fuel stats safe all the time..my truck runs awesome but I don't know if it will have the traction I need....I will not be mudding....

Good point, I didn't plan it but isn't acc 12 volt power shut off during start up...like how the radio shuts off when you are cranking but it';s on in the start position?? I just paid attention to that today getting in and starting up..

I decided to wire a custom relay system to power the lift pump where the relay is activated by a 12volt circuit from ignition system and is powered by alternator. I don't see a problem with the lift pump being power when the key is in the on position being that the pump has an internal regulator and if there is an over pressure situation the 14.2psi valve will open, relieving any pressure that would build if the regulator goes out. This would be very similar to bumping the starter and starting it half way through the cycle. Other than a good prime does anyone see a problem with this?

I don't know if this has anything to do with it, but in addition to the symptoms I've talked about the wait to start light is on longer than it ever has, about 15 seconds, and it the time it stays on doesn't change based on temperature... It has been up to 85 and as low as 26 in the mountains and it is on for the approximate 15 seconds....not sure if this was vital to what anyone was thinking about... In my opinnion it just adds more validation to Mike's ECM conclusion.

Just wanted to say thanks to you guys who helped me out here....If any of you find out what would causes the ECM to not power the pump during the first second when you turn the key into the "On Position" please let me know.....at this point all I care about is that I have 12 volts at the lift pump, and I do.... thank you very much and Happy late Thanksgiving!!!Will

Dumb question, but..the air dog powers either from battery or alternator per the instructions....so is there an issue with the Rapter pump getting 14 volts? How would you wire it?

I actually am using the rapter which plugs into the stock wiring harness....I would really like to hook a 12 volt switch up to give it a full 12 volts to be sure... Do you see an issue with this? Also.... Did u remove your grid heaters? Did it set a code, and how cold will the truck start at.... I noticed that I get voltage fluctuation between 13.2 and 13.75 within the first minute... Which I thought were the grids, but it was 74 degrees...what do u think is the deal?

No apologies necessary.. I would've said the same thing... for the split second it happens, I didn't get an accurate reading.... at that point it was getting a little too dark and I kinda wanted to post to see if anyone knew what was goin on, ya know..... I could sit there and measure voltage at different points chasing wires, but all that would do is fuel frustration.... I think I will try the idea you had to see what the voltage is when being bumped...to see if it is in fact 12 or if it is 8.5 like is is when turned to the on position at his point. thanks so much, Will P.S. I am jealous of your truck.... 6 speeds are really hard to come by in CA.

Yes I understand and have experienced the 2-3 second pressurizing up when first turning to the on position and 25 seconds when bumping for around 5 years now..... what I am experiencing now is no pressure at any time turning the key to the on position and only .5 second pressure increase from 0 psi when bumped. It maybe gets to 10 psi during this brief time. I'm pretty sure that all i have to do is find the item that is drawing too much current...creating the voltage spike that tells the ECM to lower the voltage.... what do you think?

So this morning the truck started normally with the gauges showing pressure upon the turning to the on position......but when I got off work... it was back to no pressure when turned to on position... it was 65 degrees outside.... Mike, I trouble shot the using all the standard voltage diffeential checks in the link you posted, and I had a 0.00 volts at all juncture points... I am getting a new relay just to see what happens.....not sure if there is a safe way to wire the air dog using an independant 12.6 volt circuit.... Anyone have any ideas without running the risk of running too much juice to the pump/system/sensors...etc???? --- Update to the previous post... Hey Joe, Let me know how and if it works, thanks for letting me know that you are dealing with similar simptoms... Will --- Update to the previous post... How much do you want for it?

When I disconnected the battery cables and reconnected them after five minutes the voltage to the pump is back up to 12 volts and the pump is on when the key is turned in the on position, like it always has...I will do the test tomorrow when I get off work..

Here's the deal.... I checked voltage first thing in the morning while bumped starter.... 8.5 volts at pump....voltage at the relay is 12.59 volts... drove for about 20 miles.... same result after the truck was shut off for 15-20 seconds.....The good news is I figured something out..... I wanted to see if disconnecting the batteries would do anything for about 5 minutes.... all connections are clean..... I hooked cables back to posts, and it is totallly back to normal.... I went through around 8 cycles of key on-see pressure for 5 seconds-start-drive-turn off... it is back to normal...Not so comforting that I do not know what the issue is... no codes, and running exactly the same....lift pump has 12.55 volts in the on position for 5 seconds, and same for when it is bumped...I ran all the functions of the electronics(a/c, blower motor to max...etc..) to see if something is drawing excessive voltage causing the ECM to lower voltage after a code is triggered.Everything is fine now, but if we could still work on this I would really appreciate it.

just drove 160 miles today through up hills and down hills..... Idle at stop 17 psi-WOT @ 70 to 75 14.5 ish(elecrtrical)....19psi at idle and 15.5 ish at WOT(liquid filled mechanical gauge) at around same speed.... I have been using both, I think i mentioned this but cant remember, just to make sure there isn't something getting damaged.... What do you think.... I am usually around 14 volts while charging. I also checked fuses and relays.

Thanks so much, I will try it.... it is running at normal pressures when it starts... is it still a possibility that the air dog 100 is having a strain to work or at least more than it should?

I have not upgraded recently, shouldn't it always have the lift pump run around 25 seconds if the starter is bumped....Not sure if there is a PCM issue or what? My battery voltage is 12.6 volts, 13.98 to 14.00 running after the heater/s turn off. Please forgive this stupid question.... How often should this update be done... I was familiar with an update but that was around 8 ish years ago.... what causes this need for an update?I know these questions are maybe old news but I am still learning the details on the 98.5-02, and would appreciate anything you guys got..Thanks,Will

I have a 99 5.9 24 valve 2wd, auto..... My fuel pump is not powering on anymore, when the key is placed into the on position. With the fuel heater on my "On Position voltage is around 11.8 to 12.0 volts.....it has been around 45 in the mornings here, and my grid heater/s are cycling normally. My issue is that my fuel pump only starts running when I start the engine. There is no lag time, it starts normally and the grid heaters stop cycling after about 30 seconds plus or minus. I do not have any fuel leaks and am running 17 psi at idle as soon as both fuel pressure gauges (electric and mechanical) top out about 1 second give or take after it starts...... this is not what it did for the last 4 years.....Also when it is bumped it turns on for a split second and shuts of right away, it doesn't even get to 10 psi and pump shuts off. there is no voltage going to the pump... it is not the pump's issue... can anyone shed some light.... everything else is functioning normally and no light has turned on.Thanks,Will