meijerbrantm Posted April 16, 2010 Share Posted April 16, 2010 (edited) Well first I'd like to say hi. I've always been quite the Z enthusiast and finally picked myself up one. It's a 240z running MSnS-E with an L28ET in it. I knew it wasn't running 100% from the get go. So I picked up myself a wideband and started to get to work. The symptoms that I'm having is that under load it seems to die. If i'm accelerating by just barely touching the pedal, it'll usually go okay, but the second I put it down the floor I hear what seems to be nothing. So yesterday, I actually started screwing around with the tune. When I had it first, at idle it was doing around 12-13 on my AFRs. I used the map that mobythevan has on here, and well my afr's are now in the 14's and it seems to idle at about 800-900 rpms. So not bad... Taking it for a spin that day, it actually seems to accelerate quite a bit better, so I'm thinking that this tune has to be better than what I had before. Although once I get into a more generous load and try to build any boost, the car again seems like it has fuel cut. So I just kept on driving it and decided that i'd get it home, i'm seeing around 14-16 afrs with no load, so I'm thinking I'm not too bad. It's lean but again if it's not doing this under a hard load, it shouldn't be damaging. Anyways, so I keep on driving and all of a sudden any fuel I'm giving it is now starting to cut.. the car is hesitating and I'm thinking that I blew something up. I get it pulled into a parking space, turn it off. Try to start it, and it just keeps turning over and no start. So I load my original tune, same thing. Now, I have the noisest fuel pump and to me I feel like it was making a lot quieter sound when I have the key turned (the fuel pump is not relayed, just permanently on if key is turned). Anyways, can't get it to start, get a buddy tow it home. About 5 hours later, I say what the hell and try to start it, and low and behold it starts. I try to rev it, and i'm seeing my afr's jump to 20's and the rev is missing for sure. So I'm assuming the high afr's were to cylinders just not firing, but at idle again afr's are normal and it idles fine. So, I'm just thinking that my fuel pump may possibly be faulty and that I may be dropping fuel pressure under load. Do you think I'm taking a step in the right direction? I have a walbro 255 inline that I can slap in there and try it out. I've replaced the plugs (which could be possibly fouled from running rich on the old tune [what plugs would you say i should use? i threw some NGK Coppers in there because it's what I used on my turbo charged vr6 jetta that i used to have and ran awesome]). Any other advice you'd give me? I put a screwdriver to all my injectors and I can hear all of those actually shooting, so I don't think it's those. Any help would be appreciated. Oh other question which may just be stupid on my part. My AFR Gauge and AFR's in MS are not equal. I have them grounded to the same place, but not powered. Also, this could be why, but for my ground (lc-1 by the way) i just attached all 3 wires to one and grounded them to the same place as MS. Should these 3 wires just all be separated and attached to that or is it okay what I've done. Thanks oh and here's a picture for fun Edited April 16, 2010 by meijerbrantm Quote Link to comment Share on other sites More sharing options...
DREW RBZ Posted April 16, 2010 Share Posted April 16, 2010 Well first I'd like to say hi. I've always been quite the Z enthusiast and finally picked myself up one. It's a 240z running MSnS-E with an L28ET in it. I knew it wasn't running 100% from the get go. So I picked up myself a wideband and started to get to work. The symptoms that I'm having is that under load it seems to die. If i'm accelerating by just barely touching the pedal, it'll usually go okay, but the second I put it down the floor I hear what seems to be nothing. So yesterday, I actually started screwing around with the tune. When I had it first, at idle it was doing around 12-13 on my AFRs. I used the map that mobythevan has on here, and well my afr's are now in the 14's and it seems to idle at about 800-900 rpms. So not bad... Taking it for a spin that day, it actually seems to accelerate quite a bit better, so I'm thinking that this tune has to be better than what I had before. Although once I get into a more generous load and try to build any boost, the car again seems like it has fuel cut. So I just kept on driving it and decided that i'd get it home, i'm seeing around 14-16 afrs with no load, so I'm thinking I'm not too bad. It's lean but again if it's not doing this under a hard load, it shouldn't be damaging. Anyways, so I keep on driving and all of a sudden any fuel I'm giving it is now starting to cut.. the car is hesitating and I'm thinking that I blew something up. I get it pulled into a parking space, turn it off. Try to start it, and it just keeps turning over and no start. So I load my original tune, same thing. Now, I have the noisest fuel pump and to me I feel like it was making a lot quieter sound when I have the key turned (the fuel pump is not relayed, just permanently on if key is turned). Anyways, can't get it to start, get a buddy tow it home. About 5 hours later, I say what the hell and try to start it, and low and behold it starts. I try to rev it, and i'm seeing my afr's jump to 20's and the rev is missing for sure. So I'm assuming the high afr's were to cylinders just not firing, but at idle again afr's are normal and it idles fine. So, I'm just thinking that my fuel pump may possibly be faulty and that I may be dropping fuel pressure under load. Do you think I'm taking a step in the right direction? I have a walbro 255 inline that I can slap in there and try it out. I've replaced the plugs (which could be possibly fouled from running rich on the old tune [what plugs would you say i should use? i threw some NGK Coppers in there because it's what I used on my turbo charged vr6 jetta that i used to have and ran awesome]). Any other advice you'd give me? I put a screwdriver to all my injectors and I can hear all of those actually shooting, so I don't think it's those. Any help would be appreciated. Oh other question which may just be stupid on my part. My AFR Gauge and AFR's in MS are not equal. I have them grounded to the same place, but not powered. Also, this could be why, but for my ground (lc-1 by the way) i just attached all 3 wires to one and grounded them to the same place as MS. Should these 3 wires just all be separated and attached to that or is it okay what I've done. Thanks oh and here's a picture for fun Noisy fuel pump to me is an indication of either a pump that is going out or a pump that is having to work too hard to deliver the fuel. Do you have a fuel filter before the pump. I had a case a while back where the fuel tank was full of crud and was killing the pump. Check the fuel filter and check the pump are two things I would do. Quote Link to comment Share on other sites More sharing options...
meijerbrantm Posted April 16, 2010 Author Share Posted April 16, 2010 Noisy fuel pump to me is an indication of either a pump that is going out or a pump that is having to work too hard to deliver the fuel. Do you have a fuel filter before the pump. I had a case a while back where the fuel tank was full of crud and was killing the pump. Check the fuel filter and check the pump are two things I would do. well, i've read that the MSD fuel pump is stupid loud anyways. There is no inline fuel filter, but from what I can see, in my tank, i don't see any debris (fuel cell). The pump has 5k on it and i've heard them going bad in less than that... so i guess it's worth a try. Quote Link to comment Share on other sites More sharing options...
meijerbrantm Posted April 19, 2010 Author Share Posted April 19, 2010 For anyone that may have been curious. The splash foam inside of my fuel cell must have deteriorated a little at one point. Some pieces of it were all jammed inside my fuel pump. Replaced the pump with my Wabro 255 and it's now running great! Quote Link to comment Share on other sites More sharing options...
DREW RBZ Posted April 20, 2010 Share Posted April 20, 2010 Nice work! How old is the foam in the cell? Quote Link to comment Share on other sites More sharing options...
meijerbrantm Posted April 20, 2010 Author Share Posted April 20, 2010 Nice work! How old is the foam in the cell? i don't think that old, like 4 years maybe? It actually all looks okay inside, but one piece just must have escaped. I think I may just put some sort of screen in front of the drain inside of it. Now to tune the thing... Running way too rich haha. Quote Link to comment Share on other sites More sharing options...
meijerbrantm Posted April 22, 2010 Author Share Posted April 22, 2010 So... Another issue, before when I was getting fuel cut, i would see the boost gauge hit up to 6 psi... now without fuel cut, i'm getting only 2... Now I know there is a difference between leaner and richer air, but a 4 psi difference? I just don't see that as being right... Oh and does anyone know an easy fix to a leaky oil feed? I'm assuming I can't just pick up replacement parts at autozone or anything.. Quote Link to comment Share on other sites More sharing options...
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