i have been having problems with my car's gas mileage, i was reading up on other threads and some ppl have the same problem..

one thread mentioned changing out the ecu's couz the f22b doesnt have a knock sensor like the h23 does, so i was hoping ya could clear that up for me..

my first question is, is the knock sensor that important? should i actually look into getting one installed?

and my other question is, should i just replace my ecu? maybe with a p39? i read in another thread that the p39 ecu doesnt require a knock sensor..

one reason i think its the knock sensor is because at idle, i feel small vibrations throughout the car

any help would be greatly appreciated

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by lqd44 &raquo;</TD></TR><TR><TD CLASS="quote">i have been having problems with my car's gas mileage, i was reading up on other threads and some ppl have the same problem.</TD></TR></TABLE>

Did you try the suggestions in the other threads you were reading? What were the results?

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by lqd44 &raquo;</TD></TR><TR><TD CLASS="quote">one thread mentioned changing out the ecu's couz the f22b doesnt have a knock sensor like the h23 does, so i was hoping ya could clear that up for me.. </TD></TR></TABLE>

H23's have knock sensors. DOHC F22Bs don't. You read correctly.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by lqd44 &raquo;</TD></TR><TR><TD CLASS="quote">my first question is, is the knock sensor that important? should i actually look into getting one installed?</TD></TR></TABLE>

If the ECU expects a knock sensor then yes, it's important.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by lqd44 &raquo;</TD></TR><TR><TD CLASS="quote">and my other question is, should i just replace my ecu? maybe with a p39? i read in another thread that the p39 ecu doesnt require a knock sensor.</TD></TR></TABLE>

If you can find a P39 for the JDM F22B then it would probably help otherwise add the knock sensor to the block and plug it in so that the P14 H23 ECU is happy.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by lqd44 &raquo;</TD></TR><TR><TD CLASS="quote">one reason i think its the knock sensor is because at idle, i feel small vibrations throughout the car</TD></TR></TABLE>

If you have no knock sensor you will get a CEL. Read any codes if there are any and address the issues that the ECU reports.

Otherwise read read read the archives and FAQs. This has been covered many times before.

Pirate

 

I had a healthy f22b, i drove it for about 20,000 miles on the h23 ecu with cel the whole time. I think it washed the rings, becuause before i gave the motor to a friend, it was smoking like crazy, and burning lots of oil. I think the ecu was making it run rich. it would average about 23 highway and 20 city mpg.

 

ok, just one last question. why would they put a ecu that requires a knock sensor into a motor that doesnt have one? or is the ecu in it right now just a h23 ecu and not the jdm one.. do u kno what ecu the f22b motor is suppose to come with out of the factory?

 

They dont put that ecu in the car that comes with that motor, its just like any other car, the car comes with the correct ecu to power the motor.

 

where can i get a p39 ecu?

 

I have a f22b dohc in my 92 Accord wagon, its runs awesome and gets better mileage than my original single cam motor, and a lot more power. The car is a 5speed and runs the stock ecu, no problems what so ever, i even had it dynoe'd.
It made 117hp and 128 ft lbs torque to the wheels, which is equal to about 152hp and 163 ft lbs torque.

 

you can always bypass the knock sensor on the h23 ecu.
I havent done it yet on my car cuz im building up the parts for it but i have on my friends car and it works

 

how do i do that?