Steven Bui

Hi guys I need help I have a 01 civic 5 speed with the 1.7 vtec motor with around 175000 miles. My car is in safe mode and I had it put on a scanner it said it was the vtec solenoid Now I replaced the solenoid did a tune up and oil change and reset the computer with a scanner and it comes out of safe mode I can rev motor to red line but as soon as I start to drive the light pops on and I can’t rev over 4000 rpms Any thoughts or advise of what should be my next step or what else could it be anywhere I call wants me to bring it in and get a dyno test done but want to charge me a arm and a leg to do so Any help would be greatly appreciated

mac25

Any recent modifications, replaced parts or services?

Steven Bui

No just the vtec solenoid and tune up oil change I erased code with a scanner but when I start to drive it goes right back to safe mode

mac25

The oil is 5w20, and it's in the safe zone on the stick, right, not high or low?

The vtec system is engine oil governed as you may know.

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Also after resetting the codes with a scanner, have you tested the wires to the vtec solinoid for signal?

Steven Bui

The oil is 5w-20 at perfect level I haven’t tested the new solenoid how would I go about doing that with a ohm reader right? I am not exactly a mechanic but I’m no dummy either

mac25

No, if the solinoid if new, from Honda, should be fine.

You should check the wires to the solinoid from ecu, for control voltage.

Steven Bui

Yes the solenoid was new I’ll check the wires leading to it is there a certain voltage it should read and I’ll check them get back with you I appreciate your help with this

sdaidoji

iTrader: (1)

Steven Bui

Ok I checked the solenoid wires I am getting a reading of 12 from ecu

mac25

The 12v was when you were driving, above 3400rpm, throttle 80%+?

You should not have voltage to the solinoid at idle. I was thinking you would test resistance from solinoid wire to solinoid exterior, and continuity from the wire from ecu yo solinoid.

I'm not 100%, but I think the circuit goes

Battery 12v+--->relays/fuses--->ecu--->vtec control wire--->grounded back to battery via vtec solinoid connection to head.


On a side note, when you replaced the solenoid, you replaced the whole unit right not just the top solinoid but the lower part of the valve? The reason I ask is just to make sure the oil screen is new or clean.


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If all checks out from ecu to solinoid, then the last possibility is that some how a vtec control pin, inside the valve assembly, is stuck (possibly from carbon build up). Though this would be pretty hard to accomplish.

NDNV

New VTEC solenoid is a Honda OEM?