Not 240 but same engine, Stutter

[alazare619]

I have a 1995 Nissan Altima SE (ka24de) I figure i'd try the 240 forum as there more popular then the alty's and you guys know more :P, I've owned it for about 3 years now it has never ran perfect but did its job, now its time to sell it as im moving and eventually will purchase a z32 92 TT 300zx anyways. The stock intake box broke and I put together a shorty ram intake using the stock plastic piping but after start it will act like its dieing out i've tried seeing if its not sparking right by disconnecting plugs from the disy, also adjusted adjusted the timing by the disy, ive also noticed that the valve that attaches to the exhaust i belive egr seems to be smoking maybe dirty, there is also a loud noise in the valve cover or head that i cant track down that is very loud tick. Ive owned a 240sx prior and know a knock sound as i threw a rod but this is a little diffrent well alot. If anyone can help me figure out how to test my oil pressure and bleed the hydralic lifters would help to the power band is healthy but there seems to be a slight hesitation before it revs up half second to a whole second almost. Also the plugs that are in it are pregapped ngk's that i purchased from advanced i belive does anyone have the specs on the gaps. And in the intake you can hear what sounds like a gurgle. like when you pull the plug on a drain and the last bit of water flows through.

PS: im getting codes P0105, absolute pressure sensor, p0134 wich is front ho2s and p0141 wich is rear ho2s heater could someone take a picture of a mapsensor for me so i know wich it is i know the car has mass air flow but not map

[loyalone]

did these codes come after you put on the intake, or were they there before? sounds like the intake isn't sealing somewhere and letting air past the mass air sensor, which could set an o2 code, and possibly the map code. check for intake and vacuum leaks.

[alazare619]

it had codes before but i parked it for along time then the eprom (ecu) memory cleared cause of dead battery for over a year, now i do remember that prior the 02 aux and main sensors where throwing codes along with knock and trans shift range but now there not... the map sensor on the other hand i took off the little metal plate and cleaned it with some rubbing alcohol 90 percent cause i noticed the plate was redicously dirty and now its throwing the code and idling weird...im wondering if this 3inch intake / filter is to much air for the map to handle maybe?

[alazare619]

at the time in wich i cleaned it i was thinking it was maybe some kind of ambient air temp sensor or something like that this is the only car ive ever owned that was obd2 so some of the sensors i still dont understand.

[loyalone]

the map sensor monitors engine vacuum, you modifying the intake shouldn't effect it. you could try unplugging the mass air flow meter and running it that way to see if it runs better. REMEMBER THIS WILL SET A CODE FOR THE MASS AIR, so just remember that next time you check codes you can ignore that code.

[alazare619]

i think i fried the map actually, i f*** up i thought i turned the car off when i plugged it back in and it was actually in ignition so i might try just grabbing one from a salvage or buying a new one is there any test for it? ill try the maf too but last time i did that car wouldnt start at all

[loyalone]

if you un plunged it with the key on then all you should have to do is clear the code. unpluging it with the key on wont' hurt the sensor. but it will set a code.

[alazare619]

i cant remember when i plugged it in but i think the car was either on or running but the car was then in ignition was a day or two ago and was kinda tired...but i remember seeing the car was in ignition (start position)...


wow i butchered that....

Translation: when i went to reinstall the map (didnt know it was the map at that time) The car was either running or the key was in start position, cause when i got in the car the key was in start but it wasnt on...and Im pretty sure it was running the more I think about it.. Do you know where i can find specs (ohm test) for the map sensor or a link to the nissan manufacturer manuals where it might have the info on the specs.

[loyalone]

i'd clear codes and see what comes back, do you have a code reader?

[alazare619]

No I had to put the ecu into diagnostic mode manually turning the nob all the way clockwise then all the way coutner clockwise and coutn the check engine light blinks.

[alazare619]

Ok this morning i cleared the ecu ran the car for about 20-30 mins shut it off repeated since the ecu wont pick up codes cause of the 2 drive safety, anyways it is still poping up rear o2 heater and front o2 sensor and absolute pressure sensor, im positive i must of fried the map sensor some way or another does anyone know how i can test the altima map sensor i can take a picture of it if needed or does it need to be tightend down onto the metal piece a certain amount maybe?

[alazare619]

bump to the top

[alazare619]

Ok so today i went out side and decided to disconnect the maf it took 2 cranks but bam she fired right up and ran perfect up to like 3k rpm then it just would cut out like a Governor. Now this leads me to believe that (A) she is in limp mode and (B) the maf is either dirty or faulty anyone know any checks? and how to clean it I read that rubbing alcohol can clean it.

[loyalone]

the auto part store should have maf cleaner, but if you can't find it then you can use brake clean. be very careful not to break the wire inside of it, i wouldn't even touch it with a q-tip. just spray it down good. sounds like this could be one of your problems.

[alazare619]

ok did the maf cleaner still no good tried it with the stock box and filter and with the cone filter without the box. long as the maf is hooked up it will just die. if the maf isnt hooked up it will run. While i was at the auto parts store the guy told me to check the IACV and it got me thinking IACV (idle air control valve) since it has to do with vacuum could be the reason its causing it to throw map check, but i dont get as to when i disconnect the MAF it runs and idles perfect.

[loyalone]

still sounds like to me air is getting around the maf. are you sure you don't have a cracked intake tube or hole somewhere? if the maf is working correctly it will usually compensate for a bad map sensor. however if the maf is bad or disconnected it relies on the map sensor and tps sensor to calculate fuel and timing. so if it works with the maf disconnected then i would think is has to be maf related.

[alazare619]

kk you wouldnt know of a way to trick the map into thinking its working perfectly would you like a maf bypass?

[loyalone]

i don't know how to test a map sensor with out a compatible scan tool, other then if you unplugged it. it should still run with out it.

[alazare619]

do you think if i went to the local nissan dealership they would have specs on ohming or volting out the maf sensor "back probing" what my auto parts store said..

[loyalone]

im not sure if you can check a maf that way, but you could ask them.