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madmax240

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Discussion starter · #1 ·
Hello everyone. I've done some searching around and can't find any definitive answers. I've just successfully completed my first sr20 swap...well success is a relative term I suppose...
What I mean by success is that I can start it right up. After that it gets a little foggy:lamende:...It idles okay for the most part but I can hear a random misfire occur here and there, not enough to really register on the tach anyway. If I finesse the gas pedal she'll climb the rev range to 4500 or so but if I stomp on it, it'll stumble to about 3k, misfire(skip), and then bounce between 2500 and 3k until I let my foot off the pedal.:scratch: Also (Also? WHAT DO YOU MEAN ALSO?!!:gaah:)if I allow the car to run to operating temp the idle degrades and will drop real low (300-400ish)then go back up to normal, and then drop,normal,drop,normal, drop...until it eventually dies off.:WTF: I also have a wideband meter telling me that the car is running between 10.8:1 and 11.5:1 at idle which seems a bit on the rich side to me? Dunno. Mainly I just want to get the car on the road, its been months, so to have it started, but not driveable is REAL frustrating! Oh, and I replaced the MAF sensor with a new unit as well.:feedback:
 
Discussion starter · #6 ·
Ill definetely check for the air leaks at the piping. The Maf however was replaced with a brand new unit as it was what I suspected originally anyway. Would unmetered airflow leaking from the piping cause a 3k stallout? Thanks for the help so far, keep her coming!
 
Discussion starter · #7 ·
Ill definetely check for the air leaks at the piping. The Maf however was replaced with a brand new unit as it was what I suspected originally anyway. Would unmetered airflow leaking from the piping cause a 3k stallout? Thanks for the help so far, keep her coming!
 
Discussion starter · #9 ·
Can't say that I'm real familiar with how to check codes. Any insight or links that I could be referred to? What exactly do you mean by "re-grounding"? Do I just run the ground wire straight to the chassis?
 
Discussion starter · #14 ·
Sorry, it sounded to me like maybe advice was being sought after to better tune his standalone ecu. I wasn't aware that we could check our air temp reading,now I'm unaware how. So to thrasher, I apologize, as for the rest of those whom have been following this thread in any way, I apologize for posting the same comment twice. Most of my posts are done from a phone and sometimes in a confused rage I hit a button twice!
I'm gonna double check wiring for the time being. I didn't find any wiring that was done wrong necessarily so far but I did find some wiring that was soldered, but not shrink wrapped,so not all was in vain. Furthermore, I found a connection down low from the lower harness I believe. I think it might be a connection for the speed sensor? Its a small connector that looks like it adapts to a blade ground, it has two wires, one is yellow with a green stripe, the other is yellow with a black stripe. Can't find where that connection goes, so any insight there would be appreciated. Would the speed sensor not being fully hooked up cause a poor running condition?

As stated before the car starts and runs, I even drove it around the block. It just stumbles on acceleration and then jerks hard as it bounces the revs between 2500 and 3000 rpm. On that little drive around the block I did notice that the speedometer was on (its digital) but wasn't registering what speed I was going, it just showed zero. I am however getting a good clean tach signal.hmmmmm...<---------CONFUSED!!!
 
NP dont worry mine runs lol got parts from a bone yard Relax if u get pissed of about workong on ur car stop and take a few to calm down. Things will work themself out becasue pissed off u will overlook stuff. Yes it is a A/F problem it is in limp mode. Passenger side kick pannel by right foot theres ur ECU turn the screw to the right all the way then turn it back to the left all the way. The lights will blink. Go to home depot. Get a PVC pipe about 3 inches long then get another to cap it off air tight! then drill a hole into it and place of the maf. Threw the hole blow air into it u will hear a hissing noise. Here is what i made to look cost about $4
Image

Sorry image so big. I hooked up mine to my air compressor and set it for 5psi threw the regulator and lesten then u can uyse soapy water instead of brake clean and listening for RPM change for a vac leak
 
Discussion starter · #17 ·
Okay, we'll thanks to Mr. Thrasher I now know how to pull codes and pulled them on mine. I believe its throwing a 12. Do the codes normally get repeated over and over again? And to confirm I was reading it right, it was one longer flash followed by to shorter flashes, and it just did that over and over.
 
Code 12 is MAF related.... a few things could be wrong. Are you runnin stock MAF or z32. Also if you have made any wiring done to the pigtail to make it fit make sure u are using the correct wires. 1 is 12V, 1 is ground, 1 signal to ECU. Check wiring and if conversion to z32 was made then your ECU needs to be reprogramed. I put some spade connectors to my stock wiring so i can run the z32, SR20, and KA24 MAF with ease. All u have to do is plug in the wires to the correct connection marked with diff color tape.

But anyway 12 is maf related. Not responding, incorrect voltage, to high of voltage... let us know what u have and then we can continue
 
Discussion starter · #19 ·
Okay, I tested the wires to the Maf sensor(its just the standard SR Maf). My 12v power and ground both flow 12v. The white signal wire registers 1.4v at idle and up to 2.5v at WOT. keeping in mind of course that WOT still doesn't climb above 3k rpm.
 
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