TheRadBaron

My question is in regards to how well a VG30I engine responds to performance modifications of the intake and exhaust. I'm working on an engine swap in my '87 Pathfinder. As much as I would have liked to swap in a VG33E, I ended up going with another fresh VG30I. While I'm working on it I'm attempting to increase the performance a little bit without spending a bunch of money. I have a set of Pacesetter headers installed that dump into a 2" single exhaust with a free-flowing performance muffler. That should be a big improvement in flow over stock. Looking at the stock air cleaner it looks like the poor motor is trying to breathe through a straw. That little pipe that connects the "cold air" duct into the air cleaner housing has to cause a significant restriction. I thought about cutting more holes into the housing to let more air in but I don't really want to feed the motor the hot engine compartment air. I have this K&N air filter lid that has a large amount of filter media built into it. If I modify the air filter housing by cutting out most of the top and attaching the K&N lid I should be able to get a lot more air into the housing. The lid would protrude through the hood so I'd seal it to the bottom of the hood with foam to keep engine bay heat out and cover it with a cowl induction hood scoop. I also plan to carefully cut out the charge heater grid in the throttle body for every last bit of flow and as insurance against the grid crumbling into my new motor. Now, I'm a gearhead/hot rodder from days gone by but I always fooled around with carburetors and I don't have much experience with performance mods to fuel injection systems. I've heard that some systems can readily adapt to basic performance mods like intake/exhaust but others cannot. How does the VG30I system like these sort of modifications? Can it adapt to these type of mods and provide a performance increase? I'm trying to get more performance and I can live with dodgy running while the engine is warming up, etc. but I don't want to do these mods if they're just going to cause trouble and make the truck run worse than stock. What do you guys think? Thanks.

Thanks for the info. I think I'm going in a different direction now, though. I have a '99 Pathy with the VG33 that's about dead from rust. I'm going to look into swapping that engine and engine management system into mine. I'm going to start a thread about that so please chime in if you have any insight.

My '87 Pathfinder with the VG30i recently suffered some significant engine damage when it blew a head gasket and overheated. A few of the pistons are damaged and the bores are scuffed and scraped. I'm looking into the options available to get my truck back on the road. I'm considering having the engine bored and installing new pistons but it would (or could) be a lot quicker and easier to buy a good used engine and just swap it out. I'm finding a lot more of the newer VG30e motors locally and I'm wondering if I could use the long block or short block from one of these instead of having to locate an early "i" motor like mine. I'd love just swap the "e" long block into my truck and use my "i" intake and everything. Looking around on Rockauto suggests that the "i" and "e" motors used the same heads. I'm hoping that they used the same blocks, cranks, etc, too. Looking at part numbers for long blocks might suggest that the cranks/crank snouts are different between the two, though. Anyone have any insight? Thanks.

I'm pretty sure that I bled out all the air. I loosened the little cap on the upper radiator hose and filled it through that port until everything was full. Do these motors have more of a bleeding procedure than that? And as far as the head gasket goes, it's not showing any of the classic signs. There's no evidence of coolant in the oil, no steam or coolant smell from the exhaust, no sign of oil getting into the cooling system. I think the coolant loss could just be that it was all boiling off through the catch tank. Every time I stopped the tank would be boiling away and dumping coolant all over the ground from its overflow tube.

I've owned my '87 for 30,000 miles or so and it's always been a great truck. That all changed on my last road trip, though. I'll try to give some background of the sequence of events without rambling on forever. It was hot out, I was pulling a small trailer, and running the AC on the interstate. Maybe asking a bit much of the poor truck but I've done it a lot in the past without any trouble. The gauge always shows the truck running pretty hot under these conditions but it's never gotten into the danger are of the gauge and never used any coolant. In fact, the cooling system has always been perfect in the past. Anyway, we're cruising down the road and the gauge starts to rise into the danger zone. I pull it over and it's boiling over into the catch tank. I let it cool down a bit and find that the radiator is really low on coolant. I look at the radiator cap and the gasket is rotted and parts are missing. I figure that the system wasn't fully pressurized and it just boiled off the coolant. I fill up the radiator with water and go down the road to Autozone and buy a new cap, and top up the system again. I hit the road and about 10 miles later the top tank of the radiator blows apart. I think that it was the original '87 radiator so I figure it was maybe just brittle and didn't like the full pressure that a new rad cap provided. At this point I have the truck towed to my destination. While I'm there I install a new radiator and thermostat. I fill it up but I now notice that the engine is running a bit funny. The "cadence" is off while cranking and the idle is just a slight bit rough. I drive the truck around and top off the system a few times. It's now consistently running hotter than usual, though. Also, I notice that it's having oil blowby into the air filter that it didn't used to. But other than the slightly rough idle the truck runs great. On the way home it starts running in the danger zone after about 30 minutes. I pull over and it's boiling over again. I let it cool a bit and add more coolant. Back on the road, things are looking alright for another 30 minutes or so. At this point I try to turn on the heater and it's blowing cool air even though the engine is piping hot. Every once in a while the heater would blow a gust of hot air and the temp gauge would dip down a bit at the same time. I pull it over again and go through the same thing, adding more water. Back on the road this time, the gauge stays right in the middle and the heater is blowing hot. I begin thinking that everything is cool but after maybe an hour this time it starts acting funny and running hot again. From this point on I have to pull over every 20 minutes or so and fill it up. It's constantly boiling over, running hot, and won't blow hot air. Anyone have any ideas? I'm sure that it could be a blown head gasket but I don't know how that could prevent the coolant from getting to the heater core. And it's odd to me that for about an hour of the trip the heater worked, the engine ran cool, and it didn't seem to lose coolant or boil over. I'm kind of at a loss with this one.

No, it's not that the pedal doesn't go down at all. In fact, it goes down more than it should. The front brakes are operating but the rears aren't. It's just that when the pedal is pushed down and any of the bleeder valves in the rear brakes are opened, the pedal doesn't go down any further like it normally would. It's probably just a bad master cylinder. I have a new one on the way that should be here today. I'll report back with my findings. Thanks.

I'm at one of those stages in life where all of my vehicles break at the same time. I ran into something odd on my the 1999 Pathfinder that I just bought today. I didn't have time to look into it further than I did this evening so it might be something obvious, but I thought that I'd take a few minutes and ask here first in case it was a known problem. My truck has rear drums. When I bought the truck I noticed that the brakes were acting strangely. In my experience they felt like maybe the rears weren't working. I had my wife help me look at them today and this is what I found. I had her pump the pedal and I cracked the rear, driver side bleeder valve. Fluid came out, pedal went down, just like normal. We did this another time or two and then no more fluid came out when the valve was opened. The pedal didn't go down, either. I moved to the passenger side rear and nothing came out there, either. Pedal didn't go down. It was like the valves weren't even opening. So then I moved to the rear load-sensing proportioning valve. I had her pump the pedal and I cracked the bleeder on the prop valve. Fluid came out, pedal went down. After that, same story of no fluid and no pedal movement. At this point I had to call it a night and I didn't look into it any further. Any ideas what could cause the rear brakes to not get any pressure? I know that it could be a number of things but I thought that it was worthwhile to ask here and see if anyone has had a similar experience. I'm an old hand at working on brakes but I'm pretty new to ABS and load-sensing prop valves. Thanks.

I just bought a '99 Pathy that only came with one key. This is kind of a beater truck and I'm not willing to pay the $80 each to get some key copies with transponders. Does anyone know how to disable the immobilizer? I know that people sometimes take the chip out of the key and glue it onto the steering column in a location that allows it to register to the immobilizer, but I'd prefer to do something a bit more thorough. I'm guessing that you could trick the immobilizer into thinking that the chip was present by jumpering some wires together in the ignition switch harness but I have no idea which ones. Has anyone attempted anything like this? Any other good ideas or techniques out there? Thanks.

Alright! I went to the junkyard and pulled a $15 distributor today. Got home, put in in my truck, and it fired right up. I took it for a 10-mile test drive and it runs and drives great. I still need to fine-tune the timing, reset the codes, etc., but I think it's safe to say at this point that the problem is solved. Not bad for $515. Thanks everyone for the help. Cheers.

No kidding. Sheesh. I guess that I missed that part about code translating. Thanks very much for the tip. I was just about to start looking for a "no spark" flowchart but now I have a better place to start. Wish me luck.

Alright, I went out an got some information and symptoms. I'm thinking that there's more than one problem here. The first weird thing that it was doing is related to the fuel system. When I turned the ignition on to being getting the codes from the computer, I left it on for maybe 30 seconds while getting my phone ready to record the MIL flashes. After about 30 seconds with the ignition on, things started to happen under the hood. The fuel pump was cycling on and off, over and over again. On for a few seconds, then off for a few. Then on again, etc. I could hear a sort of "swishing" noise under the hood that sounded like maybe fuel rushing though the lines. When this was happening it was making MIL act really strange so I couldn't get the codes. I took out the fuse for the fuel pump and that stopped the pump from cycling with the ignition on. But there were other relays or devices clicking and whirring and going crazy under the hood. I'm an electrician and it sure sounded like relays or contacts opening and closing very quickly. They sounded more like they were coming from around the motor and I couldn't feel any of the main relays in the two relay boxes actuating. The MIL was still going crazy, dimming when certain things under the hood were clicking and blinking nonsense patterns in time to the underhood noises. This went on for about 30 seconds, then suddenly stopped. After everything stopped clicking and whirring the MIL stabilized and I was able to read the codes. Here's what I got: -0101 MAF sensor -0201 #1 fuel injector circuit open -0304 Cylinder #4 misfire None of these would seem to cause a "no spark" condition to me. Plus, there seems to be something weird going on with the fuel system. I don't see any leaks anywhere. What could cause the pump to cycle like that? Maybe a faulty fuel pressure regulator?

Thanks for all the information and responses. I didn't really have much time to fool with it last night so I just checked for spark by pulling off a plug wire, popping a new plug into it, and grounding the plug body to the motor while my daughter cranked it over. No spark present. I tried it on two different plug wires. I checked all the fuses and looked for any obvious problems with connectors under the hood and found nothing. I'll be back at it after work today and I plan to pull the codes as a starting point. The PO told me that he changed the fuel filter, fuel pump, and crank position sensor. I didn't get the impression that he was a very experienced mechanic so hopefully those parts were replaced correctly. I can hear the fuel pump run when the key is turned on but I haven't checked for fuel pressure.

Hey guys. I just took a gamble on a 1999 Pathfinder that I bought non-running for $500. It's a 3.3, AT, 4x4 with 196,000 miles. It looks like it was a pretty well maintained machine for most of its life and it's overall in good shape. The previous owner told me that it's a 1999.5 and that it's kind of odd because it takes some 1999 parts and some 2000 parts. I don't think he really knew a lot about it, though. He bought it and drove it for 6 months or so until it suddenly started running really bad. He and some friends just started to throw parts at it without doing any real diagnostics or troubleshooting until he got discouraged and sold it...to me. My preliminary testing shows that it has no spark. I haven't gotten much farther than that. I checked all the fuses and pulled the distributor cap to look underneath. Everything looks alright. I have an '87 WD21 that I love dearly and I've gotten pretty good at working on it. Being able to pull the codes off the ECU by using the diagnostic switch has been really handy and helped me fix it a few times. This 1999 is the first R50 I've owned so I don't know a lot about it. I tried searching around a bit for some answers but I'm not having much luck. I'm working crazy hours and trying to get this thing on the road as quickly as possible. I guess what I really need to know is (1), where is the ECU located? It doesn't seem to be under the passenger seat like my '87 and (2), can someone link or describe how to pull the codes from the ECU using the diagnostic switch or dial? I've come across a few descriptions of the process but they haven't been very clear to me. A while back I found a really good description of the process but now I can't find it. Those are the main things that I need to know, but while I'm asking; Are there any common problems with the 3.3 that cause a "no spark" condition? Thanks a lot.

Wires and connections simply getting wet isn't usually enough to cause a fuse to blow in a 12V DC system. I agree that electricity and water don't agree with one another but if a fuse blew every time a wire or connection got wet it would be almost impossible to drive in the rain. If the water IS a factor in making the fuse blow there's something else wrong. There's enough road spray under the truck to totally drench the top of the fuel tank and fuel pump when driving on the highway in the rain. That's how mine got wet.

So my '87 recently started blowing the fuel pump fuse. I at first figured that it was the fuel pump going bad but I've done some reading here and now it seems that the problem might be caused by bad wire connections on the top of the fuel pump and fuel gauge sending unit assembly. Here's a post that details the problem. http://www.nissanpathfinders.net/forum/topic/22462-fuel-sending-unit/ A summary is that the wires to the fuel level sending unit corrode where they pass through the metal cap and that causes them to short out and blow the fuel pump fuse. What I don't understand is how this would happen since I don't think that the fuel gauge has anything to do with the fuse that runs the actual fuel pump. I studied the wiring diagram for a while and the fuel gauge fuse seems to be included with the rest of the instrument cluster and totally separate from the fuel pump. Plus, when the tank is full I believe the fuel level sender is basically shorted to ground anyway. This causes the gauge to read "full" and the resistance increases as the fuel level drops. Am I thinking about this correctly or am I missing something major here? When my fuse was blowing it was raining hard and the top of the fuel tank (along with the rest of the truck) was soaking wet. Then I replaced the fuse and it didn't blow but the pump wouldn't run either. Once the truck dried out the pump ran again and the truck ran fine. I'm tempted to just buy a new fuel pump and sending unit assembly but I don't really like to just throw new parts and money at a problem without understanding what the problem is. Thanks for any insight.