PROBLEM With EGR system & a/f ratio ! ! !
 

civic 94, d15z1 vx (vei vtec-e)

problem #1
when i disconecting EGR velve sensor & EGR control solenoid valve, check engine does not Light On :( is it normal?
https://www.fuelly.com/attachments/fo...7606ffecfe.jpg
https://www.fuelly.com/attachments/fo...e6f315bed5.jpg

problem #2
engine work on rich A/C mixture, it can see on spark plugs (i replaced spark plugs many times) now standing ZFR4F-11 (NGK)

problem #3
engine lose power, it feels good when i ride at hi rpm.

problem #4
Fuel consumption 9-10 litres/100 km (23 MPG) in city. hwy (30 mpg):confused:

replaced:
oxygen sensor.
map sensor.
throttle angel sensor.
new changed oil in engine & gear box (+ oil filter)
AIR filter
OIL filter
Fuel filter
Ignition Timing is ok
:confused:
please tell me all reasons on this problems

Very poor fuel economy indeed.

Possibilities:

1) Leaking fuel tank.
2) VTEC solenoid valve is stuck closed - 4 valve per cylinder operation full time.
3) Very bad misfire condition - either too much air, too much fuel, or weak ignition (spark).
4) Engine problem - check cylinder compression and leakdown.
5) Parking brake not disengaging (unlikely).

fuel tank checked and not leaked.
compression is (9.15 kg/cm). 130 PSI
Parking brakes is not a reason. i know this 100%

what about VTEC solenoid? please tell me how i can see valve is stuck closed or not?

p.s.
i interested more about first problem
symptoms starting when engine has warmed up to normal operating temperature

Sounds like a similar problem I had in my former '95 VX. The enine ran fine until it got to operating temperature. Then the check engine light came on. When I accelerated slowly or when cruising at a steady speed, it lost power and bucked. Under hard acceleration, it felt fine. My Honda mechanic friend advised me it was likely clogged EGR ports. Rather than removing the intake manifold to clean the ports, he told me to disconnect the vacuum hose coming from the EGR valve (I think there was a T connector with two other hoses joining at the T) and insert a broken golf tee (without the head) into the line and reconnect it. This solved the problem and the car ran fine afterwards. The hose I'm referring to was found somewhere between the passenger side of the valve cover and the throttle body (somewhere near the red circle in your second picture).

For starters, it looks to me like you have your vacuum lines connected wrong. The diagram I have shows a line going from the intake manifold to the middle port of the CVC valve (the green and white thing). There should be a line going from the other CVC valve port to the bottom port of the EGR solenoid valve (the one you have circled in your first pic). The remaining solenoid valve port gets connected to the EGR valve.

Does the check engine light come on for about 2 seconds when you switch the ignition on? If not, the bulb could have burnt out, or someone may have removed it to make the car easier to sell.

Are you sure you have the proper ECU?

Does the check engine light come on for about 2 seconds when you switch the ignition on?

when i switch the ignition, check engine light come on 2 -3 second.
about ECU i dont know. :confused: which mark must be?
you think what its not original ECU? tomorrow I inspect
+ clutch disc inspected and no problem

this problem does not appear always but often.:confused:

If this is a US market VX, it should have a P07 ECU. I'm not sure about other markets. If the ECU has been swapped out for one from a non-EGR equipped car, it would explain the lack of EGR error codes.

yea sounds liek a bad egr to me. my s-10 used to buck at low gears at low speeds (where it shouldnt buck) and the mpg never varied from 25. i could gun it everywhere, interstate trips, slow accel, etc but wouldnt vary, plugged it and mpg instantly shot up.

Question...why are you disconnecting the EGR in the first place?

since I cleaned EGR system & valve