Engine Flood/Miss Fire

[Nissan2367]

Ok here is the background...I just put a RB25det s1 in my 91 240sx.Mods:Greddy Intake ManifoldQ45 Throttle Body2.75" Intercooler PipeGreddy FMICHKS Timing BeltGreddy Oil PumpSyko Performance Turbo ElbowMegan Racing 3" DPHKS Hi-Power 3.5" ExhaustGreddy Boost ControlerApexi Intake---------------------Ok here is my problem. Before the car would "fuel cut" and "rev limit" at about 2k rpm. I was told to buy a MAF and it would fix it. 300 later it didnt fix it. i checked and reset the timing because it was off a little. Once i did that it idles perfect and reads 14.2 a/f at idle. now if i so much as touch the gas it "floods" and the wide band goes so rich it does not read anything! I can drive the car but it is so slow and shakes like its going to die if you touch the throttle. I am out of ideas!!! Its the stock ecu with no tune and i know i need to get that done but the car should run lean if anything with the mods i put on it! I am willing to try anting to get this on the road. i have about 1 month before snow and it would kill me not to drive it this year! any help and the sooner the better would be awesome! Thanks guys, i am new to the RB and nissan area...

[Coolwhip]

how are your vitals and have you boost leak checked your engine?

[fast_s14]

whats your fuel pressure set at? Did you check to make sure your TPS is reading right?

[Nissan2367]

- There are no boost leaks-The fuel pres is set at factory (has factory reg) but i have never checked the pres... how would i do that?- I have no idea how to test the tps, i unplugged it and the car ran worse so i put the stock rb25 tps on the q45 throttle body and it still runs like crap! Any other ideas? I am use to working on Hondas and now i came back to nissans... my first 240sx was a nightmare!!! This one is turning into one too!

[BoostFab]

- I have no idea how to test the tps, i unplugged it and the car ran worse so i put the stock rb25 tps on

if you don't have a fuel pressure gauge, get one. and if you don't have a fuel pressure regulator, get one, so you cna adjust your pressure.

[240z4u]

Do you have an FSM? And are you SURE you have the right ECU?

You will notice, I live in Madison. I might be able to help you out but honestly am not sure if it will be too soon. Trying to get my house ready for winter!

Evan

[Nissan2367]

Yeah man if you could help me out you have no idea how awesome that would be! Do you work at checker on the east side? I hear there is a guy there that knows his ****! I am pulling it all apart again tonight to make sure everything is lined up perfect (timing wise). I was wondering if a there was a spot to line up the crank to on the block or if you have to put the timing cover on and line up the balancer. Let me know asap i will be working on it all night! I need it to run before i put it away for winter or it will kill me all winter! Thanks!

[Nissan2367]

Ok so i lined all the timing marks up DEAD on tonight. The piece of **** still runs like ****! It backfires out the intake and exhaust. I am out of ideas besides selling the **** and getting another honda! I have never had good luck with Nissans! Oh also no engine codes!

[ANVIL]

what is your ignition timing set at?

what fuel pump are u running? if its upgraded like it should be, you will have to adjust to proper fuel pressure anyways.

another thing, i noticed you have the q45 throttle body, im not 100% sure but i think i remember somewhere that it wont run right w/o a tune with that and the greddy manifold. like i said im not sure on that... anyone else want to confirm?

[WhatsADSM]

You are SURE the MAF is good and the wiring is good?

I would get a multimeter and tap into the MAF signal at the ECU. Then check the voltages when you are idling and when you touch the gas.

[Nissan2367]

I am running a Walbro 255lph pump. The timing is set at stock timing, i lined up the timing marks and thats it. i am not sure if it needs a tune with that throttlebody but it should at least run with it and if that was affecting it it would be running lean not rich.i guess the other thing i hear it could be is bad coil pack or packs.the MAF is brand new OEM, It was the first thing i bought when it as running like crap.The wiring harness was mad my Wiring Specialties and i sent it back in so they could review it to make sure everything is perfect and it all checked out. i think i have the right ECU (Came with the clip) But is there anything i should look at to makes sure?Thanks for all the help guys

[Nissan2367]

Well today i ordered a AEM fuel pres reg. i am just wondering what everyone is running for fuel pres? It has stock fuel injectors, rail and a 300zx tt fuel filter all pushed by a Walbro 255lph Pump.If this does not fix it i have no idea what will! Into storage it will go!

[darksurfer81]

I may need to get a FPR myself, what site did you get it from? Also where did you get the new MAFs I may replace those too to try to fix my problem.

[Bluefire]

Did you check timing with a timing gun or just lined up the belt...

[darksurfer81]

Gonna try with a timing gun this weekend when the weather cleans up. That is the best way right?

[Bluefire]

Gonna try with a timing gun this weekend when the weather cleans up. That is the best way right?

That is pretty much the only way to check ignition timing...

[nyc240sx]

yea

[Nissan2367]

I lined up the marks. the first time i tried it with a timing gun every time it flashed it was dead on but when i reved it it went WAY off! The first time i lined up the timing marks on the cams to each other (how its done on a honda ) so now i lined up everything the correct way. the only thing i am wondering before i take a timing gun to it again is if the timing mark on the pully should line up with first mark to the left or the first mark on the right... this is from sitting in the car. i have looked around and all i found is someone saying line up up counter clockwise bla bla bla... this is easier.also does anyone know where to find out what to set my FPR at?-------------------------------------I found a guy in my home town that had a brand new oem maf that sold his to me... so i have no idea where to get another one! darksurfer81it shounds like your having the same issue with you car, if you figure it out let me know asap! This is really pissing me off! Also how much did you buy your car for... i am thinking of selling mine the way it sits so i can buy a bike and pay to move.

[240z4u]

Your email does not work, email me.

Your car isn't worth crap as is. Just a basket case basically. Get it back together.

Evan

42psi vac line off.

[mattleegee]

So 42psi should read from the fuel pressure gauge for stock injectors?

got my car started up and it sounding like it was choking when i revved, it idled fine, some ticking but might be the lifters or something... hopefully

[Bluefire]

With the vac line off the regulator, fuel pressure should be 42 psi, regardless of injectors.

[jey_253]

I had this happen to me once so u can try my problem. I have a LC-1 Wideband and for some reason the LC-1 temporarily crashed and wasn't putting out correct voltages. I Shut car off, checked all connections and restarted it and haven't had problems since. It made car flood out horribly though....so check your O2 sensor

[mattleegee]

I had this happen to me once so u can try my problem. I have a LC-1 Wideband and for some reason the LC-1 temporarily crashed and wasn't putting out correct voltages. I Shut car off, checked all connections and restarted it and haven't had problems since. It made car flood out horribly though....so check your O2 sensor

yeah i dont have an o2 yet, i bought a greddy a/f but it didnt come with a bung and need to find the right thread size so i can weld it on the DP, im also waiting for my water+oil temp gauges to come in