Hi,

The gas mileage just dropped from 30mpg to 22mpg and the car is REALLY sluggish. I found this thread on SR20Forum that has some information, but I wanted to know if any local SR20 owners found a simple fix that worked.

If not, it looks like my Sunday is pretty much 'done' having to go through all this crap. Any suggestions are greatly appreciated.

Thanks,

Darren

Additional Info on my B14:

• No codes on ECU
• TPS has been replaced
• Car hesitates a little
• Throttle is OVERLY sensitive to inputs
• Slight sputtering from exhaust manifold area on cold start
• AC has full charge, but still sucks

 

i would start with the 02 sensor.
how do you drive? floor it from every light? or just drive normally?

 

I'll check the resistance on the sensor, tomorrow. As far as the way I drive, I'm usually pretty easy on the pedal unless I have to merge into fast moving traffic. My driving habits have been pretty consistant since I've owned the car (8 months) and this sudden drop was VERY noticable in the last four fill-ups.

 

the TPS may have been replaced but it sounds like you need to reset it. Check ignition timing, check for exhaust leaks, vacuum leaks, leaks in the intake between the MAF and the throttle body, etc.

 

agreed! just do an all over check and see whats missing/old(needs replacement)/leaking. Itll take you just a lil bit but its worth it trust me and most the time youll find the problem. If none of that works hit me up i probably have another solution.

 

I really hate working on the car when it's this damn humid =0)

I'll fire up the Nissan shop manual on CD-ROM in the morning to be sure I'm testing everything the right way. If you can think of any other areas to check, please let me know.

Thanks!

 

If you take a cigarette, and blow the smoke into the engine bay, you can see if there's a vacuum leak by the smoke getting sucked in on the intake side, and if there's an exhaust leak you'll see the smoke being pushed away from the exhaust leak ( you have to unplug your fans to do this...otherwise the flow from them will make the test pointless). I'd try to get my hands on a scanner if I were you, and clear the learned memory, and start over. If that doesn't work, pinout all the sensors that may affect this condition: TPS ( i know you said you just replaced it, but there may be high resistance in the wires somewhere), EGR (could be stuck open-but wouldn't affect anything while cruising), O2 (its responsible for your AFR), MAF (could be putting out false readings), ofcourse if you don't have access to any of these tests, or you don't understand what im talking about, PM or call me, and i'll explain it better. Does the car Idle fine?

 

well honestly i dout its the o2 sensor because from my past expierences when you dont have an o2 sensor then you tend to blow out alot of smoke out the exhaust!

 

The car was having problems with the idle about a month ago. When I replaced the TPS, the idle problem when away. As far as the exhaust, it smells a little rich, but it's not blowing a lot of smoke.

 

did you try the knock sensor? that would make it run rich and when you give it gas it would bog down and cause it to have shitty gas mileage and lack of power.