s14 zenki sr into s13.....no start, suspected maf issue

[kooltacos]

let me start by saying i have spark and injector pulse, yes i know it sounds stupid but i do not have the factory maf, although i just ordered one. I have tried starting the car with the maf unplugged hoping it would go into limp mode, i am not trying to drive the car, i just want to make sure it runs before my 30 day warranty is up. Also I tried to use the ka s13 maf becasue the pinouts are the same and it plugs into the s14 sr harness fine. blk/white is power, black is ground and white is signal, the colors and functions are the same on both harnesses. is it not true that both the s13 ka and s14 sr use the same principal to send air flow rate to the ecu....aprx. 1 to 5 volts through operating rpm? my question is if they use the same concept why wouldn't the ka s13 maf work, i dont expect it to run well, but i would think it would at least sputter, and i cant get that. is the sr air flow rate mapping for the ecu that much different from a ka or what? or am i missing something obvious here? i have heard of people using sohc mafs and z32 maf but why the frick wont an s13 ka maf work at all? they all use the same friggin theory! the only thing i can figure is ecu mapping is waayyyy different on the two cars or i have a bad maf, any insight would be appreciated

[Justin35ll]

Well the dohc ka maf won't work, but the sohc will. I don't think it would cause a no start though.

[240life]

Yeah usually a MAf sensor isn't a no start issue. Have you checked the spray pattern of the injectors?

[kooltacos]

Can anyone tell my WHY the sohc maf will work and the dohc wont? Does the sohc have pixie dust in it or something? They both work on the same principal don't they? also, i got the car to crank up using carb cleaner so its obviously is not getting enough fuel at start up, it will stay running but will not rev past 2500, i assume becasue there is no maf. should my car be able start up with out a maf?

[kooltacos]

no i have not checked the pattern because i wanted to run some fuel through it, who knows how long old fuel has been in the rail.

[ballinnmiami240sx]

I would check the simple things.

Fuel......make sure your fuel lines are route right and you have about 40 psiSpark...spark checkTiming..Put number 1 cyl to TDC and check the CAS alingment.

After all these are comfirmed good then jump into wiring. It has been proven that the sohc maf works, but not the dohc. WHY? dunno. The s14 to s13 swap involves about a 20 wire solder job.

[Kalypso]

an engine will start without the MAF plugged in.

thats for sure. it wont idle well, but it will turn over.

I would check the simple things.

FuelSparkTiming

After all these are comfirmed good then jump into wiring. It has been proven that the sohc maf works, but not the dohc. WHY? dunno. The s14 to s13 swap involves about a 20 wire solder job.

there's a lot you havent explained... thats why I hate walls of text.. check lists are better

Does the starter crank the motor?

or is the whole thing, just dead when you turn the key.

[kooltacos]

I have sparkI have fuelMy fuel lines are correctly routedI got the car to run with carb cleaner

[kooltacos]

yes yes and yes,

I am way beyond any starter issues, I'm a noob to sr's but not cars.

BTW for every one that says a dohc maf from a ka won't work, they're wrong, (kinda). The car won't crank with the ka maf unplugged, but it will run ok with it plugged in. It runs very rich but it runs! Would a sohc maf not do the same

[kooltacos]

when i say crank i mean crank up and run.

[hpballer76]

sohc mafs only work on s13 sr's.... u need a s14 sr maf.. 69f00 if you have a zenki motor or 69f01 if you have a kouki

[kooltacos]

am i the first person to use a dohc ka maf on an s14? there is so little info on this topic. the car actually runs pretty good with the ka maf but it runs fat at idle. i just ordered a 6900.

[kooltacos]

this was a combination of problems, I did a voltage drop on the battery during cranking and it was dropping to 7 volts, even with the battery charger on it at 80 amps, guess this wasn't enough to run the ecu or injectors etc, but it would turn the starter over. New battery solved all issues.

[sileighty85]

check your maf wiring on the ecu. that's what happen to me a month ago. i thought it maf that won't let me rev past 2500, but turn out to be a loose maf wire by my ecu.