my car have the problem that it drin to much fuel.it goes 11.87miles/gal on city when i drive like a grandmom and 16.62 miles/gal on highway at 60miles/hour .....
theres no conections failure... i clean all and i solder it!! there is no leaky inyectors... theres no leaky temp sensor.. theres no leaky all the others...
the inyectors are fine...i recently clean it in a injector lab... they remove it and disasembly all and remplace o ring and other stuffs.... my car smog a little, very little and i adjust the trothle body sensor to .45volts ... i clean the trothle body mechanic with carb cleaner...i clean the mafs.... the mafs volts on one terminal is 1.46 volts.. and the other is 0volts and other is the voltaje batery..... the temp sensor read ok.. it work with 0.82 volts on normal temp in the car....
car at idle and warm
o2 sensor = 0.55 voltsmafs = 1.46 voltstemp sensor = 0.82 volts..
i dont have the aiv ....there a 3 littles conectios like a canister had and it have no conections... there are under de trothle body and i think that one goes to the aiv and other i dont know. my car revs fine but drink to much fuel....
i replace de o2 sensor with other that is not the original and is not the oem... it works in a 200sx but i dont know if it work in a 240sx. ....
would i put the original o2 sensor? there is a new autozone in my city and it sell the 02 sensor in 30 dollares. there is the oem for 240sx 1990.
what do you think of my car problem? it have 169k miles...haaa...the timming is 15° =) !!!! i check the timming to!!
11.87 miles per galon problem HELP
its about 28-30 ps !!!!! all the tires are the same presure!!.... if my car start roug in the morning.. maybe the coolant temp sensor fail? if the coolant temp sensor fail, produce a bad gas mileaje? ... my rpms are fine.... myy car dont bogg... and it accelerate very fine...
the problem is in the morning.. i have to warm a little , because if i put the gear into D, the car try to die!! my car in the morning(cold) have to rev a little, but my car dont do it. it rev to 850-900 rmp .
the problem is in the morning.. i have to warm a little , because if i put the gear into D, the car try to die!! my car in the morning(cold) have to rev a little, but my car dont do it. it rev to 850-900 rmp .
check the coolant temps connection for corrosion. If there is green crust inside that connection that could be your problem clean it out real good then slightly bend the female pins in a little in the connector to make a tighter fit.
Bring your tire pressure up to 35psi. That will help a little in the gas milage department.
Bring your tire pressure up to 35psi. That will help a little in the gas milage department.
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Q45tech
- Moderator
- Posts: 14296
- Joined: Tue Apr 30, 2002 3:19 am
- Car: 1990 Q45 342,400 miles 22 years ownership with original engine
1995 G20t 5 speed 334,000 miles 16" 2002 wheels - 205/50/16 Sr20ve vvl
Not familiar with the EXACT MAF voltages on 2.4L but the only things that control injector open time are MAF, rpm, and TPS. Assuming temp sensor says 176F and KS are not signaling a retard.
Fuel pressure can enrich the flow but only at a square root rate [43.4/34= 1.276 square root=13% more flow. Does your fuel pressure go up at idle when the vacuum line is removed from the regulator?
You will need a Nissan Consult [diagnostic computer] to read and record the injector open time under various rpm and load [tps voltage positions] along with MAF voltages.
Not knowing the rpm at which you get a 1.46 MAF reading, but most Nissan [Q/SR/J30 idle at 1.1-1.2].
Fuel pressure can enrich the flow but only at a square root rate [43.4/34= 1.276 square root=13% more flow. Does your fuel pressure go up at idle when the vacuum line is removed from the regulator?
You will need a Nissan Consult [diagnostic computer] to read and record the injector open time under various rpm and load [tps voltage positions] along with MAF voltages.
Not knowing the rpm at which you get a 1.46 MAF reading, but most Nissan [Q/SR/J30 idle at 1.1-1.2].
some day... the maf conections hurt, and i cut the wires and solder it into maf..... maybe i solder in a wrong position.... !!!! i will check your tip about fuel pressure and vacuum line!!!!!!!! i have to go now to the school , but ill back in 2 hours!! =)..... here is a other question... if o2 sensor is not the oem or if o2 sensor is not the original part... it will affect to my gas mileage?
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Q45tech
- Moderator
- Posts: 14296
- Joined: Tue Apr 30, 2002 3:19 am
- Car: 1990 Q45 342,400 miles 22 years ownership with original engine
1995 G20t 5 speed 334,000 miles 16" 2002 wheels - 205/50/16 Sr20ve vvl
The O2 sensor can signal the ecu in a 20% range. In other words a lack or wrong switching signal could increase fuel consumption up to 20% on the highway probably 10-15% around town.
Compare the idle MAF voltage to another equal engine, same with cruise = rpm reading at same speed.
Substitute a 300-330 ohm resistor for the coolant temp sensor [WHEN WARMED UP 176F] as a check.
Compare the idle MAF voltage to another equal engine, same with cruise = rpm reading at same speed.
Substitute a 300-330 ohm resistor for the coolant temp sensor [WHEN WARMED UP 176F] as a check.
i restore all tires pressure....the pressure in the tires were 24-27 psi restore all to 35ps !!!
the graphic show 3colors... green that correspond to voltaje output from maf and have 1.4-1.6volts... the red that show the voltaje batery and the black that correspond to ground !! the other pics show you a space in the car respect to other pieces!! filter... inntake and trothle body!! its only to show the position of wires and maf in the car!!
the graphic show 3colors... green that correspond to voltaje output from maf and have 1.4-1.6volts... the red that show the voltaje batery and the black that correspond to ground !! the other pics show you a space in the car respect to other pieces!! filter... inntake and trothle body!! its only to show the position of wires and maf in the car!!