Hey guys... been a long time. Anyway, I was just coming down the mountain yesterday and my truck had some big problems. Well, besides the fact that my hubs are screwed(free or locked they are always locked, good thing they have a lifetime warranty). Anyway, since I was just nearing empty I figured that my truck was out of gas. Since we had two vehicles, my dad went and got gas. Gas didn't help either. I was barely able to get home. No power at all. It drove the best when I was running it at high rpms... but even then, no power, and sometimes it would have NO power and it would start slowing down. So I figured it was a clogged fuel filter so I replaced the filter today. Still no go. But before I started the truck, I listened to the fuel pump, I figured I'd wait for it to build up pressure. Usually it pumps, then I hear it stop. It never stopped. I figured it would take a little longer since I had drained the fuel line, but it should have built up pressure. Does this sound like I've got a clogged/faulty fuel pump? I was thinking that the sloshing around offroad combined with a near empty tank that I might have dislodged some gunk and plugged something up. Anyone have some ideas?

 

How many miles on the truck? What Engine?

 

I think I've got 170,xxx miles. 3VZE(3.0l V6). The engine was replaced at 100,000 miles, and the speedo is off by 10%. So really, the engine has 63,000 miles. Now as far as the fuel pump/filter goes, I have no idea when the last time they were changed. So I figured the fuel filter needed to be replaced no matter what. Still trying to figure out what's going on though.

 

Check you spark plug wires first. Had similar problem, studder no power at low rpm. Replaced fuel filter no change. after new plug wires, OEM ones, it was peppy again
I also think on your truck there is a fuel pump diagnostic plug, when you use a jump wire it runs the fuel pump with the key on. Then you can check for function as well as pressure. No need to drop the fuel tank if the pump is not the problem
HTH
Cheers
Nathan

 

How long should my fuel pump run for when the key is in the on position but the engine is not running? I thought I remembered that when I turned the key to on, the fuel pump would turn on building up pressure, then would shut off after 5-10 seconds, and wouldn't run until I turned the key. But the pump never stopped running. Does it just take a few minutes to build up pressure in the system again? I let the pump run for at least a minute before I started it, and it didn't run after that. I think I might pick up some new plug wires on my way home tonight.

 

Tried new plug wires, didn't work. But I've got some more info on what the engine is doing. I can rev the engine up, but when I try and hold it at a specific rpm, the rpm's cut back down to idle and it starts to stall. If I continue to hold the pedal at that same position, after a few seconds of sounding like it's going to stall, it builds the rpm's back up, then repeats. Anybody have a clue what this is? If it were just an uneven idle I'd think it were a vacuum leak... but this seems like quite a bit more.

 

Does it do it quite regularly or is it irradic... I had a no power problem, although it only did it occasionally in the beginning, then later was constant. sounds like what your dealing with... ended up being a fuel pressure dampener. the truck was a 94 4runner with a 3.0 and 125000 miles when it happened.... let me know if you have more questions about it.

 

Well, this happened on Sunday, all of a sudden I might add. And it has been this way each time I've tried to drive it. It will rev up, but as soon as I try and hold it at an RPM, it loses power. This has me completely stumped. I think I'll try dropping the tank and checking the fuel pump's filter. My friend was telling me that because the fuel pumps are lubricated by the fuel, running them dry *can* cause them to die. I'm gonna try and pull some codes tonight. Any other ideas would be greatly appreciated.

 

Of course I do things backwards. I ran the trouble codes this evening and it says I have a faulty O2 sensor. That didn't seem right to me. It just seemed like the problem was something else. But just for kicks I unplugged the O2 sensor. Started up and idled rough, but now it holds the rpm's steady. I'm going to go pick up a new sensor tomorrow and hopefully I'll be back on the road!

 

well good to hear, at least its an easy fix!

 

Just noticed your sig. Why aren't you sticking with a nissan engine in the 240Z? I'd love a 240Z with a VG30DETT, or of course an engine from an R34. BTW... Have you seen Darius' 240Z with the supercharged LT1? AMAZING.