Idle problem MAF tip...

[Julio Bro!]

I was weeks with an idle problem and black smoke, I've written several posts about it. Every advice was good, so I worked with them.

I eliminated the PARC valve, cleaned the AIV and MAF, replaced the oxygen sensor, and the coolant temp sensor. Also installed new NGK plugs and new fuel filter, but the problem kept going.

My heater hose broke and so I had to take my ride to the shop, to make it worth, I told the mech. supervisor about the idle problem and black smoke...and he went: "That's the MAF." I told him it was clean and the problem was not typical of that part and he said a test was to be done.

After repairing the cooling system, they tested with another 240SX MAF and the idle corrected. Apparently I needed a good MAF, which I was gonna buy used, of course (a new one is $700). But then, when I got the car back, the idle problem was completely gone...no hunting, no smoke...nothing. I asked the mech. supervisor what could've happened and this was the answer:

"When re-installing your MAF, the mechanic cleaned the connectors throughly and pressed the connecting pins with the pliers for a better and tight contact. Then the computer codes were checked and cleared. These parts get dirty with time and the pins get a bit loose from disconnecting and connecting the harness, so apparently that was the problem."

And there you have it...include this in your idle troubleshooting: Clean the MAF resistor carefully, then disconnect the harness and clean the pins throughly. Take some pliers or suitable tool, and tighten the pins in order to get a better and tight contact. Reconnect and then clear the computer codes.

I hope this helps those of you that already tried everything else.

[#1stud]

I have an 89 and its been to turn off on me when i hit the gas normally and when i stop and its in drive the rpm meter goes up and down like crazy and sometimes it will turn off when i also hit the brakes. I have already changed the Catalytic Converter and the Oxygen Sensor and i have no idea on what to do, do you have any suggestions?

[Arrow]

Did you try to clean your MAF connectors?If you did and are still having the problems check the following:injectors (for leaks and the connections)most other aux. sensorsspark plugs (mostly to see if they are covered in carbon deposits or oil... both can be an indicator of problems)and possibly the break booster lineHope that this helps (I've got a 1990 and have had idle issues and this is about the majority of the things that I have checked to get it to run better (the MAF sensor connector cleaning really helped mine when I did it 6 months ago or so))Good Luck!

[Julio Bro!]

This sounds like the MAF alright. Clean it carefully and the connector too, but also change your spark plugs and fuel filter too. And give your system a good fuel system cleaner. Good Luck.