[titanruss]

I tried to post a topic before, and it never went through. Gonna try again.

A month ago my truck shut off while driving, turned out to be a fuel pump after getting it back home. Tank only had a gallon of gas in it, even though it read quarter tank. Replaced the pump and it fired right up. Then whenever the truck was warm, it would start and die instantly, then just crank until it eventually started.

Replaced ecm relay, crank sensor, coolant temp sensor, evap purge valve, cleaned maf. Was starting fine on a hot start for a few weeks, and now I'm having the issue again. It seems like a fuel delivery problem on startup, but it idles and drives fine. Not sure what the fuel pressure is though.

Can someone please point me in the right direction? I want to love this truck, but this is getting frustrating.

 

[titanruss]

Come on, anyone?

 

[danman]

There is a capacitor in the wiring that has been known to give problems with fuel pumps...but blowing fuses. I need to search my history to unarchive it. that could be your problem. I'm curious if may the capucitor is on its way out and venting/degrading causing your fuel pump issue. Can you hear the fuel pump when turning ignition on?

 

[danman]

http://www.titantalk.com/forums/showthread.php?t=351810

 

[titanruss]

Yea, the fuel pump kicks on when I turn the truck to the on position, but I havent blown any fuses yet. Could the relay on the board be on its way out? I kind of suspect the pressure is bleeding off, but it starts no problem when it is cold.

 

[danman]

Search fuel pump intermittent there are a couple discussions about relays and such. I haven't had any issues so I can't help from experience. What year is your truck

 

[titanruss]

The truck is a 2004. I can hear the fuel pump prime the first time I put it into the on position. If I go back to acc then hit on within a few seconds, the pump does not turn on. But if I wait another 15 or so seconds, the pump will prime again when I cycle the key. Not sure if that's a setting in the ecm for the pump to not prime if I cycle the key a bunch of times quickly though, or if it really is the relay issue that you're mentioning.

 

[danman]

look at this, might be worth a try

http://www.titantalk.com/forums/tit...pdm-ecu-relay-problems-symptoms-solution.html

 

[VRamkelawan]

I can verify that your ECM has a safety circuit to prevent your fuel pump from being primed on/off repeatedly when cycling your ignition. This is to prevent over-pressuring your fuel line as well as overworking the pump itself, leading to problems further on down the road.

It definitely sounds like a fuel delivery process, and I think one of the big determining factor is to run a pressure test on your fuel line when the no-start occurs. You can then compare this to the manufacturer's recommendation for what pressure your lines should be at. Keep in mind that fuel pressure is variable depending on demand. So another good thing to check is the fuel pump relay itself, could just be a sticky switch.

Keep us posted.

 

[titanruss]

Thanks for the reply. I figured that since this is a brand new fuel pump, it should be keeping the pressure at the correct amount right? I do feel like this is some sort of electronic issue I'm having, since the truck doesn't sputter like it is being starved when it does start.

I thought maybe it's an immobilizer issue, or a relay issue. I've been looking online and I can't seem to find where my fuel pump relay is though. From my understanding, it is built into the IPDM itself? Or is it a separate relay that I can swap out?

 

[danman]

Yea man, one of the links I posted on here shows where the relay is and you could swap it out with one similar....it's a bandaid fix and the relay will need to be replaced, but will let you troubleshoot whether or not it was the relay...or just spend $4 on a new one...lol

 

[titanruss]

Oh I'm familiar with the ECM relay swapped with the fog light relay. I bought a brand new ecm relay from Nissan a month ago. Still having the issue though

 

[titanruss]

So I just checked the voltage on the battery after it sat for about 2 hours. It was at 11.3 v, but it started right up. Idling it sat around 14v, but quickly dropped down to 12.5 and steadily dropped after I shut it down. Battery and alt are only a year old. Could a bad battery be causing an intermittent issue with the ecm and ipdm board?

 

[danman]

11.3 with no load? That seems low. That may be a problem....lots of potential problems and variables, hard to say

 

[titanruss]

I thought it was really low too, but I figured that repeatedly trying to start it would deplete the battery even more, and not start up at all.

 

[Arachnid]

http://www.titantalk.com/forums/tit...itan-no-start-beyond-basics-seeking-help.html

 

[VRamkelawan]

So I just checked the voltage on the battery after it sat for about 2 hours. It was at 11.3 v, but it started right up. Idling it sat around 14v, but quickly dropped down to 12.5 and steadily dropped after I shut it down. Battery and alt are only a year old. Could a bad battery be causing an intermittent issue with the ecm and ipdm board?

Very interesting. I've seen this happen before in my (old) brand new 2011 Civic. My fuel pump wouldn't cause a sputter, but it would delay activating or initiating at start. My battery drain however was caused by a stuck A/C Compressor Relay. This would drain my battery in about 3 hours from 12v down to 4v. Took a while to discover, but first thing's first, figuring out what's draining your battery.

LMK if you have any of the following: aftermarket sound system, HID lights, light bar, auxiliary battery, cell phone charger, power inverter, etc... Anything that adds draw to your battery that was not designed/installed by Nissan. This would reduce the immediate culprits that you can troubleshoot.

 

[danman]

The truck is getting up there in age too. It might have some electrical grimlins causing issues as well. From experience on this forum in many many reads, the electronics are sensitive and any number of things can cause problems. My dads 04 had an issue where it would die and have difficulty starting and would intermittently die, all due to bad grounds near the battery tray...caused by corrosion.

 

[Pale Rider]

I can verify that your ECM has a safety circuit to prevent your fuel pump from being primed on/off repeatedly when cycling your ignition. This is to prevent over-pressuring your fuel line as well as overworking the pump itself, leading to problems further on down the road.

It definitely sounds like a fuel delivery process, and I think one of the big determining factor is to run a pressure test on your fuel line when the no-start occurs. You can then compare this to the manufacturer's recommendation for what pressure your lines should be at. Keep in mind that fuel pressure is variable depending on demand. So another good thing to check is the fuel pump relay itself, could just be a sticky switch.

Keep us posted.

fuel pressure really isn`t all that much variable. should hold a steady 51+psi (55-52)when operating, cruising cold to hot. 50psi @wot is what I`m seeing.
what would be interesting is to know if the fuel pump voltage supply is modulated according to flow/demand...

 

[titanruss]

The truck is getting up there in age too. It might have some electrical grimlins causing issues as well. From experience on this forum in many many reads, the electronics are sensitive and any number of things can cause problems. My dads 04 had an issue where it would die and have difficulty starting and would intermittently die, all due to bad grounds near the battery tray...caused by corrosion.

That's what I was thinking as well, but I can tell pretty much when the truck will fail to start and how many attempts it will take to get it running. I'm leaning towards the ipdm or the battery at this point not having enough juice to signal the ecm to fire the injectors or something. I just don't want to spend money on parts that isn't the problem though.

What can I do with the ipdm board removed to test it with a multimeter and determine if that is the reason for this issue?