It Lives once again Fuel pump was the issue that thing runs on 51 psi on the nose thanks for all the help... Glad I pursued further Nissan Techs Kept telling me it was in the ecm or wiring but then again they have never encountered a Straight Gas K21/25
Yes it is located on the pump module. Whether it is replaceable or integrated in the pump i do not know since i have never had to work on one.
RCAV8TOR, I haven't seen a fuel pressure regulator in the system is that on the fuel pump module ?
If she is not putting out the specified fuel pressure then thats where i would start. Perhaps the fuel pressure regulator is iffy or the pump. Please let us know what you find.
RCav8tor and Edward t thanks a bunch put a fuel pressure gauge into this and found the fuel pump is only putting out 20-40 psi now it does have the green relays I have tried moving the relays around and haven't changed anything so I am ASSuming the fuel pump
I don't have another K21/25 around here right now I did test the harness between the cam/crank sensors also replaced the Mass air flow with factory part, Checked the connectors at the ecm and relay panels no corrosion noted I will check the fuel pressure and see what I get also question maybe a dumb one but there is an inline plastic clear fuel filter is this an oem part or mechanic added @ 55 psi I would think it would be a different style filter but... I have seen more odd stuff
Thanks
edward t has a good point also. Could be a flaking out of the fuel pump relay and is marked as such. Being an L02, possible it has the black relays instead of the green relays. Giving no code could relate to possible corrosion at the ECM connectors or a simple mass air sensor going south. Have seen where the mass air has gone south and not set a code.
needs to have 55PSI fuel pressure, but for all the world, I would be trying a k21/k25 cam and crank sensor (and the wire harness that connects them to the main harness) from a truck with a k21/k25 motor that I knew ran.
Have you checked fuel pressure with a gauge? Fuel filter dirty? The timing on these lifts are all over the place except at idle and WOT. At idle you should be somewhere around + or - 2 degrees and WOT around 27 degrees advanced. Anywhere else in between will be all over the board as the ECM is trying to manage RPM and Stoichiometric ratio. Sounds to me like you have a fuel issue.
Used OEM parts.... cant make this POS run Talked to local Nissan dealer and CAT and TCM no one has ever dealt with a straight gas truck up here there has to be one of you out there that has seen this Nissan thinks its the wiring harness or ecm but I cant just throw these parts at the truck with no results
Said you replaced cam and crank sensors....did you use OEM or aftermarket,these trucks have issues using aftermarket parts....just a thought....
Checked air filter, Replaced cam and crank sensor, Plugs, Here is what is happening the ign timing is dropping out meaning at high idle it will be about 27 then will drop to 0 and stumble backfire etc. or at idle will fluctuate from 5 to -4 then stumble and die no codes,
I know these have a timing chain with tensioner is this where I should be looking have been talking to Nissan Cat Tcm Techs and they are drawing blanks on what is going on someone has to have seen this before Thanks
Clogged air filter? Clogged/dirty fuel filter?