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Hey all, just installed a turbo on my 94 NA and since I have put everything togher it will run strong for like 20 sec everytime then die, by mistake just hapened to unpulg the maf sensor and the car will idle fine but will bog down when I hit the gas, I installed bigger injectors if that has anything to do with it?
Thanks

weird, ive never had a car run with an unpluged maf sensor. not for any amount of time.

bigger injectors contrubite to the bog but the car dieing i have no idear

might mean you have a bad maf sensor

waldo320 wrote:Hey all, just installed a turbo on my 94 NA and since I have put everything togher it will run strong for like 20 sec everytime then die, by mistake just hapened to unpulg the maf sensor and the car will idle fine but will bog down when I hit the gas, I installed bigger injectors if that has anything to do with it?
Thanks

You can't just plug a turbo on a NA car and not change the engine management and expect everything to work ok. You might go in depth into what you did, and that will make it easier to diagnose the issues.

Well here I go I have a s afc first gen not hooked up right now, vf11, custom side mount intercooler, sti 480 injectors, 91 legacy manifold and down pipe wrx up pipe, turbo xs blow off, custom 2" intercooler piping, the three 1/2" vacum lines that were on the stock intake pipe are now T'ed, and the one 3/4 breather has k&n filter on it, oil feed from filter attachment return into oil pan, cooling feed and return from heater core, other than that stock 94 NA MAF that will not idle without the AFC hooked up, other than that its a stock 94 BC

the car just does not idle and every time I come to a stop sign the car dies

It's the bigger injectors. You are overfuelling at idle and part way up the RPMs. We had this problem when we built the Ej20/Ej22 hybrid. And we were only running Ej22T injectors. If you gave it a little gas, you could force it to keep running. It would make good power from 2000-4000rpm and then it would just bog like nobody's business. There was nothing we could do about it until we got the E-manage installed and tuned.

Our temporary solution was to go back to the NA injectors. This made the car driveable. It would detonate terribly about 4500rpm and higher.

Also, you now need to change out your plugs. I guarantee they are fouled...

the car diesing when you come to a stop is probably your BOV. It can't be open to the atmosphere, you need to route it into the intake ducting pre-turbo. If it's open to atmosphere, this is the problem. Also, make sure you have the air line to the Idle air control valve correct.

I ran my MAF in blow through mode right before the throttle body and ofter the BOV, so I can release my BOV to atmosphere since hte MAF didn't read the air yet. Seems this works better on the NA management also as it has no function to compensate for the change in air density after compression and charge air cooling. Putting it in blow-through mode alows the MAF to read more acurate air flow.

dscoobydoo wrote: You can't just plug a turbo on a NA car and not change the engine management and expect everything to work ok. You might go in depth into what you did, and that will make it easier to diagnose the issues.

P just bolted a turbo on mine, verything else stock... it's awsome

NA cars will run "fine" without the MAF plugged in......But....... you get about 7-10 mpg.

well the question is Air in the form of my maf conected to the intake side of the turbo and the bov after the intercooler, or big injectors with no cpu mangement? ? ? ? ? why will the car not idle? ? ?

Are you pulling ANY fuel?

do you mean is fuel getting to the injectors then yes had a little gasket problem and trust me there is plenty of fuel getting to the injectors I am running stock fuel pump and yellow sti's

No, I mean, are you pulling fuel via Engine Management.

With 370 cc injectors, I ran WAY rich at idle. Then when I bumped up the base fuel pressure, the car will barely run.

I pull a fair amount of fuel out at idle, and just cruising around. I bet if you were to go driving, you would get about 10-12 mpg right now.

other than the car not idleing at all as soon as I hit boost on my guage I here a bup bup bup or what I am taking as a fuel cut really havent taken out for much more then around the block due to it stalling every time I stop and havent spent much time trying to get the afc working since I cant find the right wiring digram for my car so hopefully be able to post more tommorw night on the afc prob

I suspect you are actually getting the opposite of fuel cut, you are getting WAY WAY to much fuel. Or so I suspect.

well how do I change that put the stock injectors back in or get the afc running?

Just put the stock injectors back in for now and see if it runs fine, it should, just dont boost over 5 psi!

Or get smaller injectors. You can get 370 cc nissan injectors for $100 or so on ebay and they are good for about 12 psi (with a RRFPR)

I have been talking to the guy a few posts up about the blow through set up maf after bov do you think that could be the problem?

Until you get your fuel problems solved, ie, get it back to stock fuel at idle, I don't think you are going to be able to tell anything.

Do the stock fuel injectors and then go from there. Its a pain in the ass, I know, but you need to just get it running to start.

Remember, the injectors you are running are letting TWICE the fuel in.

http://cgi.ebay.com/ebaymotors/NISSAN-S ... enameZWDVW

http://cgi.ebay.com/ebaymotors/370cc-Fu ... enameZWDVW

quick question just happen to be installing a new turbo water pump to cure my thermostat rubbing on the manifold problem, had some $ from christmas and decided to run out to summit and buy a unorthodox crank pulley, if retard my timing some by a crank adjustment would this cure the excess fuel problem??

NO. I may be wrong but again I say No,

Hey update, reinstalled the stock injectors, double checked timing, and there is one foot flame comming from the down pipe, result fuel trims messed up since maybe the ecu isnt use to the stock injectors and is still thinking sti yellows, but can not get the afc working right have it hooked up right but still does not work, OH YAH the car will still will not idle but tonight I am going to reset the ecu and see what happens, sugestions help!!!

Try removing the AFC too. See if you can get the car to idle with the engine management as stock as possible.