Sterling

aloha from kauai,
I am working on a v6 pathfinder with a no start. I get a start when i introduce fuel directly to the throttle body, and i have pressure up to the throttle body, but no injection. The computer has supposedly been swapped with a known good one, and the haynes manual does not have wiring diagrams on the injector circuit. Does any one know if there is a cutoff that would effect the injectors but not the fuel pump? any help is appreciated.

Mr.Mike!

you could try a self diagnostic test. Perhaps the computer will tell you what is wrong. Try this link. Tolleyy has some excellent on self diagnostics.

http://www.nissanforums.com/showthre...threadid=14880

__________________
91 Maxima
94 SE-V6 4x4 truck
92 Vert project Mustang

Fixer of all things broken,
Breaker of all things fixed.

Somewhere along the way they usually end up twice as fast.

Tolleyy

Aloha bradah Sterling!
Have you checked the resitance on the injectors to make sure it's getting a signal from the ecu? You're manual should tell you the proper resistance. There's no cutoff ( like an accident shut off on fords) that I know of on the Nissan's.

Good luck!

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95 WD-21 DVD/TV system-otherwise stock kid hauler
95 D-21 KC XE 3" lift- built for rockcrawlin!

lgl2001

Sorry to post on an old thread but I am very interested to know if user Sterling solved his injector problem.

My buddy is working on an 1987 Pathfinder 3.0L 4wd Automatic after an engine install (body and used engine bought separately) and has had the same unresolved problem for the past 2 weeks. All other issues, cut wires missing connectors etc.. have been solved. He too can run the engine by spraying gas into the throttle but although fuel gets to the injectors (which shows the pump is working) the injectors will not spray.

He is pretty savvy with cars and has run all diagnostics on the computer but everything checks out and no related codes are coming up.

Any more info than previously posted would be greatly appreciated.

maier65

I am having the same problem with a '87 pathfinder. I've measured the fuel pressure up to the manifold and it is okay ~35 psi. Engine will only run shortly with fuel directly sprayed into throttle body. One thing though, the fuel relay is clicking constantly when the key is on and also the EGR solenoid relay. I talked to one mechanic(at a salvage yard..so..take with salt) and he said if the oil in the crankcase gets too diluted with gasoline it can cause problems which confuse the computer. According to this guy, the oil will get diluted with gas if it hasn't been changed in awhile. Anyway, i hope someone has the answer.

jadcock

I don't think gasoline in the oil will confuse the computer in any way. It will sure ruin the bearings if you have enough gasoline in there, but nothing that'll be caused by not changing the oil for a while...

I would remove the EGR relay to rule out that the EGR is hanging open for some reason and diluting the mixture which will not let the engine run at idle. Also, switch the fuel pump relay with a known good relay to see if you can isolate the problem to the relay. I don't think it's normal for it to be clicking constantly.

__________________
Jason Adcock
Always Tread Lightly!
1995 4x4 XE King Cab - 189,000 miles
1997 Cadillac Seville - 141,000 miles

96R50

I’m with Jadcock, verify that your fuel pump relay is good. We have a 40 ton press at work that has clicking relays once every year or so. The vibration from the press is enough to break the soldered connections from the circuit board out to the wire terminals. The press will run but clicks constantly as the vibration makes and breaks contact. I’m not saying tear your Nissan relay apart and look for a broken/loose connection, but definitely swap it out with a known good relay. If it continues to click, then the input signal is oscillating or may be the ground lead is loose and breaking contact.

maier65

The fuel pump relay was the first thing i changed, but it didn't help. I'll pull the EGR relay and see what happens. Thanks to you both for the replys!

1997XETruck

I know this is probably too obvious... I'm not sure on the Pathfinder, but on the Q the injectors are fed by a separate fuse. Have you tried checking continuity between this fuse (if it exists) and the injector harness?

Heath

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1997 Nissan XE Truck - 133,000 Miles
1990 Infiniti Q45 - 91,000 Miles
2005 Infiniti G35 Sedan - 34,000 Miles

maier65

I'll check see ,,,thanks

maier65

The injector(s) fuse is okay. With the fuel pump relay out and the EGR solenoid relay disconnected (there is a couple wires from the solenoid going to a connector with a diode symbol on it-this is what i disconnected) the clicking noise is still happening - when the key is in the 'on' position. It sounds like it is coming from the injectors. Anybody have an idea? I didn't know fuel injectors could make a clicking sound.

1997XETruck

Injectors click during normal operation... The clicking sounds like a relay chattering somewhere - have you pinpointed where the sound is coming from? Get a mechanic's sthescope - it'll make your life much easier!

Heath

__________________
1997 Nissan XE Truck - 133,000 Miles
1990 Infiniti Q45 - 91,000 Miles
2005 Infiniti G35 Sedan - 34,000 Miles

maier65

Thanks,

I took the Throttle body off and was surprised to see a huge chunk of carbon blocking the EGR and PCV valve ports. I cleaned it up as best possible without taking off the EGR valve and then put it all back together hoping for the best. But it didn't change a thing. The injectors still click like crazy and the beast won't start. Maybe the EGR is bad. Any suggestions why there would be so much carbon build up in that spot?

96R50

Does the truck have throttle body injection?

maier65

yes..