Hello all!

I have been fighting an issue with my 92 Q45 Base. I had an issue with the second cylinder on the drivers side. It appeared that the injector was leaking fuel into the cylinder and was hydro locking the engine. I actually broke the starter nosecone when it happened. (wasn't running luckily). I put new injectors in about a year ago, OEM ones. I pulled the problem one out, the O rings looked ok except they both appeared to be very loose fitting. I also pulled all plugs out to make sure I wasn't dumping fuel into any other cylinders, which I was not. I replaced the O rings on the one injector with a set off my old injectors, re installed and was still dumping fuel into that cylinder. I ordered new O rings for all 8 and replaced them. ( was thinking the ethanol could be to blame as the car has sat a lot the past 3 years. I now am not dumping fuel into the cylinder but it is running rough and dies when warmed up. I know I probably have a bunch of fuel in the exhaust system that needs to be worked out. I have changed my oil and filter 2 times due to fuel getting into the oil. when running and warmed up it is emitting white smoke and I have a strong fuel smell and I am dripping fuel out of every opening in the exhaust system on the drivers side. Fuel pump and MAF have been replaced. It was running fine until all this started. I have also done compression check and that appears to be good on all cylinders. I have had the timing chain guides done, trans re built and new drive shaft so I really don't want to give up on her.

Any input would be greatly appreciated!

Thanks.

to NICO!

Sounds like you're pretty knowledgeable under the hood, so probably know how dangerous hydrolocking can be.

I would pull the fuel rail but leave it connected to the fuel lines... turn the key on and pressurize the fuel system, and see what's squirting out.

What kind of injectors did you use? Did you lubricate the O-rings before installing them?

Heath

I used OEM purple top with yellow dot and yes lubed the O rings before installation. I have not tried that, I had assumed that it was spinning over normally now with no hydro lock issue that I shouldn't be leaking any fuel but I guess anything is possible.
I will have to give that a try at my next opportunity to work on her.

Thanks

Did Nissan include a fuel pressure test port on the F50's?

Seems like you could hook up a fuel pressure gauge, briefly turn on the ignition to pressurize the injectors, and then see what happens to the fuel pressure after you turn the ignition off.

I am not sure if a pressure test port was built into the fuel system or not, have not located one yet anyway

On a 1992 Q45 you have to tee in the fuel pressure gauge from where the hose comes off the fuel filter.

Here's a link to a slide show where I hooked up a Maxima fuel rail to the Q's fuel system to pressure test a rail for leaks after I refurbished the injectors. The Q delivers roughly 10 lbs more fuel pressure than a 4th gen Maxima/I30 so I prefer to use it for high pressure testing. In this example I blocked off the return line to capture maximum pressure on the rail.

Slideshow

http://s286.photobucket.com/user/Ridgel ... or_Testing

Also, here's a picture when I tested the Q rails on the car. I placed a blue shop towel under the injector rail while I checked the rail for leaks under pressure.

OK, I was able to finally test the fuel pressure. When running about 34 PSI which according to the service manual is where it should be. When I turn on ignition without starting, pressure builds and then bleeds off to 0 quickly. I assume that is not normal. I have been told that the fuel pump energizes with key on for a few seconds then stops until engine is started. Even with the pump shutting off, the pressure should hold shouldn't it?

Thanks all

Yes. Hydraulic locking took out one of my VH45DE after one of the flow tested injectors in the untested rail assembly leaked. It was a third party who advertises on many car forums.

Time to check the injector seals pronto!

I have not had a chance to work on the car since I tested fuel pressure and I probably will not have time until after the middle of next month. Every weekend recently has been spent getting the race plane ready for the National Championship Air Races in Reno. After Reno I plan to jump back on it.
Right now everything is 100% back together so once I have back apart and test the fuel rail pressurized with it out of its mounts to see which ones are leaking I will update everyone.

Thanks all!!