redtegy

ok. i will list all parts i have replaced. new egr valve, all egr ports cleaned (did egr work cause of egr code that is no longer there thank god), new fuel filter, did a tune up not long ago, new sensor 1 o2, new exhaust manifold/catalytic converter(due to crack in old manifold), and new stock exhaust piping with new stock muffler. my car is first of all throwing the 1164 code and according to my scanner it says sensor lean range. my car also does this thing where randomly it will feel like im driving with the e-brake and ac on then that stops and i get power back. it will do this randomly either during acceleration and/or at highway cruising speeds. its driving me nuts cause ive put about 1200 into this car just in the past few months. what could the issue be? how do i check? what do i check? anyone else have this issue?

Former User

Did you install a new OEM O2 sensor (expensive)?

Check for a loose O2 or ECU connector or loose O2 sensor wires at both locations.

redtegy

i did install a new o2 from oreilly. Part # : ES10751
i will check connections but would the o2 cause driveability issue like im getting?

Former User

It definitely could.

redtegy

well that really sucks cause i just spent 200 bucks on this one from oreilly. i really dont want to spend 300-500 on another o2. especially if it isnt the problem ya know. ill check the connection and maybe throw in the old one to see if that does anything. is there anything else that could cause the cel and the driveability issue? im still getting like 34-37mpg with mixed city and highway driving, but i want at least 40 or more and i know this car can do it.

Former User

Focus on loose connections first.

redtegy

will do. thx for the info ron. i will update this tomorrow. any and all other ideas are welcome.

redneckvtek

The thing you are speaking about is the calling card of the HX. Its called Lean Burn mode, and the D16y5 will go into a E-vtec mode where it shuts down half of the intake valves and leans out the compression ratio to ~25:1. In steady state cruise it 55 mph on flat ground, the HX can hit 55 or 60 mpg fairly easily. That motor is truly a gem for fuel economy.

If you want to know when the car is in lean burn mode, there are plenty of gadgets that you can use. The most basic is to use a code reader to monitor bank1 sensor2. When sensor2 drops from approx .8 volts to 0.00 volts, the car is in lean burn. The paramaters are fluctuating, but its usually between 2000 and 3000 rpm in 4th or 5th gear, with the TPS less than 33%

Do some reading on ecomodder.com or google the HX motor and lean-burn mode, you will learn to love it. if you want to mod the car for speed, sell the HX to someone who wants the HX because they are sought after.

Also, did you buy the correct O2 sensor for the HX model? The hx comes with a 5 wire primary O2 sensor which is actually a true wideband O2, so it is not compatible with the other versions of the civic. I know this is a dumb question, but just want to cover all the bases.

redtegy

yes its the correct 5 wire o2

redtegy

well connections were good. what i actually did was put my old o2 back in and the code has not come back yet. scanner and data checks out and driveability is better now. im gonna go to oreilly tomorrow and throw a fit till they do something for me. thx for the input guys. when it comes to o2 sensors, oem is the way to go. even if it is used oem.