need help BADLY please read!

[smokin240]

--Please read this, i know its long but its a complicated problem

I have a 93 240sx all stock and for months now ive been having the same problem with it. If it sits all night and i start it up the next morning it runs fine for about 5 or 10 min until it warms up. Thats when the problem starts, it starts acting extremely sluggish and i lose ALOT of power if im not between 2500rpm and 3500rpm, after that the car accelerates very slowly, like theres something pulling it back and just loses alot of power and jumps. Anyway I had a friend mechanic to look at it and he's not much on imports but he thought it was the coil that connects to the distributor cap, so he tested it with a volt meter and it tested bad, suppose to do .5 ohms resistance and its doing 1.5. So what I did was I went to the nearest junkyard and got a new coil to replace it. At the dealer its 240$, at auto zone its 160$ and I got it there for 75$. I was thinking not bad if it works but anyway I test drove it before i bought it and it wasnt it, it did the same thing!! I had a feeling that wasnt that problem. My friends next idea was the module behind the distributor cap. I have no idea how to test this to see if its bad, no idea on prices if i have to replace this, and my friend is going on vacation tomorrow morning... I wouldnt be so worried if I wasnt going from indiana to arizona in a couple days (moving).... Im afraid its not going to make it and I just want my car running like its suppose to. Please any help would be greatly apreciated, thank you for taking the time to read this!!! Feel free to ask questions, ill answer them as best as possible. anything to get my car fixed

[smokin240]

I forgot to add that the day it started it just started, i mean it wasnt a decline in power or anything, just one day started doing this. So it cant be a combination of things. its only one thing that i think has to do with temperature control, because it lasts longer on colder days.

[smokin240]

:help

[gumby]

well i couldnt say but you could carefully unscrew the 2 bolts holding the mafs sensor and see if the 2 wires are intact. clean it with some carb cleaner while your at it.

get rid of the aiv system if you havent maybe its stuck open.

also could take off the intake and manually check if the throttle body is sticking spray it with some carb cleaner if its gummed up

idle it while its pitch black outside easiest way to locate ignition leaks.

look for open vacuum lines.

heres a procedure for checking the fuel pressure regulator i lifted:on the intake manifold there are 2 fuel lines one is the fuel and the other is the return, you need to locate the return which is the bottom one or the one notcoming from the fuel filter. start you car and get a pair of needle noze pliers and squeez the return, if your engine revs up fast then you have a fuel problem, probably your FPR, if your FPR is bad i would replace it

check the contacts for the temp sensor

i dont really know what im talking about but it couldnt hurt to check.

could also run seafoam throught the brake booster line then change the O2 sensor.

[smokin240]

ok im going to run this by my mechanic and see if he knows how to do the temp sensor and stuff, thanks alot

[fiznat]

also check:

1. the voltage coming out of your 02 sensor... find out if you're running rich, lean, or stoich. That should really help you narrow it down.2. it sounds stupid, but do you have a clean air filter?3. look around for vaccum leaks4. do a compression test5. make sure your EGR valve isnt stuck open, or partway open

good luck man!

[skatanic28]

try takin a look at your plugs and see what kinda shape their in. hopefully they will be able lead you in the right direction. are you running hot at all? detonating? exhaust smoke?

[yellow_jacket]

Pull the codes from the ecu. It sounds like a bad electrical connection somewhere. I would personally start pulling the connectors off of the distributor, maf, and ecu to make sure that they are not corroded at all. On the ecu plug make sure there isn't any dielectric grease on the terminals and that all of you pins are nice and shiny. If there is dielectric grease, clean that out as it tends to go bad over time and cause faulty connections.

[smokin240]

guess what.... they found out its the MAF (mechanic who hooked it up to a computer). DANGIT thats going to cost me friggin 600$ to replace. AHHHHHHHHHHHHHHHHHH what to do what to do

[gumby]

lose your mechanic a refurbed mafs should cost you $95 at NAPA after core deposit. you can install it yourself 1-2-3. $600 thats fnckin criminal.

then take some of that $500 you just saved splurge $60 get yourself a generic O2 sensor the O2 sensor socket and a bottle of seafoam. disconnect the vacuum line from the brake booster. stick a funel in it and slowly (10 min for the bottle) pour it in while someone revs it in nuetral at 2000 rpm. after the smoke clears install the new O2 sensor. viola your fuel air ratio will improve you saved $440 and cleaned all the crap out of your vacuum hoses.

[smokin240]

u rock, thanks alot

[smokin240]

also, will they have those in stock?

[gumby]

i wouldnt think so but it should only be a few days at most.

[smokin240]

by the way isnt refurbed rebuilt? isnt the mafs electronic? how do they rebuild that if thats what it is? Thanks again

[smokin240]

Napa says its $425 refurbished by the way.

[gumby]

ill check with em again tomorrow i did ask and was told $95 after core deposit. i dont get what the hell is so special about this sensor that people are getting ganked over it. if they dont tell me different this time i'll get 2 of em one for you one for me so i dont get ganked later.

http://catalog.nissanpartswholesale.com/

$205 +$55 core free shipping

probly find it cheaper if you search around

[crzycav86]

You could probably get one from a junkyard for a hundred bucks

Or even try the nico classifeds... people who are parting out their cars.

[smokin240]

cool, ill check, and thanks gumby. The guy I was talking to I dont think knew what he was talking so if it is 95 ill call again and ask. I specifically asked for a refurbished MAFS for a 93 240sx, maybe he didnt hear the refurbished part? ahh well we'll see

[gumby]

http://shop.nissanpartstore.com/?make=NI&year=1993

oops i gave you info for the sohc my bad its $227

[gumby]

yeah it was $95. apparently different oem companies prices vary greatly while the quality doesnt. either theyre trying to stiff you or its all they have available. If you want I can buy it and send it. Youll save some $$$ but it'll take a few days to get there. Try calling around tell em you want the lowest priced one available. If they have it and want your business you'll get it.

[smokin240]

cool gumby thanks. but i think i got a guy on Nico classifieds that has one for sale, im waiting for a price qoute to see how much it will be for shipping (15 without). Someone also said they were having the same problem, and the easy fix was to clean the corrosion off the MAFS and try and make the connection tighter. Im going to try that and see what it does, if that doesnt work, ill probably shoot for this guy on nico. i'll let you know what happens, thanks again