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View Full Version : RB20 Running Rich, Track day Friday


beng2k
06-14-2007, 12:24 AM
Heya guys, Im in a bind.

Long story, but I really need your help. Please, I organized a track day with my buddy for Friday, and if I cant go, Im going to be terribly upset!

My wideband usually shows 14.7+/-0.1 for the first 20 secs or so when the ignition is turned to on, and after about another 15-20 secs, usually goes under 20 and reads LEN. This is how it calibrates before I start the car every damn time, which is kind of annoying, but anyways...On to the story.

Car had a leak at the O-ring on the #2 cyl, very minor, but letting it sit in the garage caused my parents to smell gas in their room, directly over the garage. So Sunday I go over to my buddies house in hull to move my recirc valve so that I can put on the strut tower bar I bought. So I leave his house after everything is done, he lives in Hull, and we had forgotten to tighten the coupler at the throttle body, so I pull over after noticing this and tighten it.

Off I go on to the highway, running a little bit warm, about 180F, its also like 30+ some with humidity at 1pm LOL, and the car rides fine, hits 0.75bar like normal, all is well. I get home, and pull the injectors out, replace to o-ring on the one injector since I had just replaced them all after my GTR injector failed because of a failed tuned ECU that didnt work

So injector fixed, drive the car, and all seems well. AFRs are in the 12.2 range under boost, around 14.7 ish on idle (stock ECU). Then I get about 5km or so from my house, then it starts sputtering for a sec or two, so I clutch in and coast, idle settles, AFRs are in the 14.7ish range like they normally are, and I drive to a nearby parking lot to check things out. (From here on out, I never hit boost.) So I pop the bumper off, check for leaks, cant noticebly hear anything, but I could feel a leak at one of the couplers.

So i tighten it cause it was a bit loose, and tighten the rest for good measures. Check the injectors and theres a leak....On the No.1 injector. Ok, time to make my way home, slowly, actually under 40k, making sure the AFRs stayed around 14 on about 15-20% throttle, still bogging intermittenly. Also, the AFRs were idling around 15.1 after I noticed the new leak. Dont make it home. All of the sudden, probably less than 2km, car starts really running terrible, so I shut it off right away and coasted it to a side street.

This time the leak is so bad when the pump primes, you can see bubbles and spray from the leak. Run home, grab the two extras plus one of the round insulator rings, and change that up on the side of the road. Start the car, massive ammounts of greyish/blusish/whitish, hard to describe smoke, smelt like gas quite a bit come out. Car was running like complete crap, almost like it was on 4-5 cyls! So i turn the car off, no more leaks anymore from the injectors, but the car doesnt run. Start it again, AFRs go right in to the 10.5 range, shut off the car. Pull the plugs, Black as hell and have yummy Sunoco 94 smell to them. Run to CT, grab 6 new plugs ($67.00 with taxes) , change 'em up, try again, Goes right to the rich side. So Im thining its flooded or something, call up the ol' flatbed...$134.52 later, its at least in my garage, and not the side of a street.

Let it sit for more than 24 hrs and I drive the beater for a day. Turn the key, wideband calibrates down to about 19.5 or so, which is 0.5 higher than normal, but close start it up, running now on all 6 cylinders again, but running pig rich at 11.0 on idle. Stop the car. Do a full oil/filter change, flushed with an extra 500ccs of Mobil 1 before adding 4 or so litres, and try and start it up. Still rich. Ok, lets kill all the gas in the cylinders and pull the fuse on the fuel pump. Engine dies. Turn off the ignition, wait a few, turn it on, calibrates down to LEN like normal...Sweet!!!! Crank it up, climbs to 14.7 for a sec or two, then shoots up to 11 AFR again. FACK. Pull the fuse, kill the gas so it doesnt seep too much into the oil and call it a night.


I have 6 more o-rings comming in, but since theres no leaks, I dont think I should pull the whole rail and everything out again. I tried spraying soapy water, but when I'd spray, it would create bubbles. This very much sounds like a leak, but I cant quite hear or notice any visible leaks. My friend says he can hear injectors clicking when it idles, as I thought maybe the injectors were stuck open. The car idles fine just has an AFR of 11.0 on my wideband, which seemed pretty good unless all that smoke comming out the back facked it up cause there was no smoke and idled fine. My ECU throws no codes. Maybe I should just clean the wideband tommorow as maybe all the sut from the exhaust smoke yesterday clogged and filled it up?

Any ideas???


----Update-----

I changed all the Orings, oil (again), and rechecked all the IC and stuff, and I managed to get it to idle around 13.5 when cold. Also, instead of showing LEN whne the WB is calibrated, it shows around 14.0. I lightly cleaned them with some O2 sensor safe carb type cleaner, both O2 sensors, cleaned the MAF.
I drove it about 0.2km and under light throttle maintained a 14.7ish AFR, and under boost around 12ish. Still nto sure though, whacha all think?

Ninjabread
06-14-2007, 12:28 AM
Someone chime in, he needs this car running by friday. Or else the world is doomed.

slider2828
06-14-2007, 01:35 AM
Well after you cleaned the WB o2, it looked like everything was caused by a leaky injector. Secondly, I would recalibrate the 02 Sensor after you cleaned it. You can do this if you leave the sensor in the pipe for 24 hours and just recalibrate OR you can take it out of the pipe and just walk like 20 feet away from your car and just recalibrate. That would give you the best idea. BUt the problem is already leaky injector and you know it, secondly when you install it, injector o rings should be oiled and not dry or it will crack. I think you can just use some nice oils to lube the o ring before installation. Sounds like something is messed up on your rail if you keep leaking in the same spot as well or you messed up something when you removed the o ring, like the o ring retainers on your injectors or something....

beng2k
06-14-2007, 09:06 AM
There are no more leaks, I replaced all 6 even after the was no leaks. Its idling around 13ish AFR and Im too scared to push the gas pedal down very far

slider2828
06-14-2007, 12:29 PM
Dude worst that can happen is get a new fuel rail and injetor. You gotta drive your car, don't be a punani....

beng2k
06-14-2007, 05:29 PM
LOL well I really dont wanna fack anything up...i got it to idle around 13.4 ish AFR, which I feel is safe enough to drive, but I am going to replace the O2 sensor for tha fack of it....I think the wideband o2 sensor coulda got facked from all the smoke that came pouring out...

mr_240sx
06-19-2007, 01:44 PM
so how is it running now Brian? is it fixed?

Ninjabread
06-19-2007, 01:49 PM
Eh she was good enough to take around the track... B's just a bit paranoid these days!

haha love ya bud