B18c6 problem, keep loosing vtec?

[compton]

hi there

ive aquired a civic ej9 with a b18c6 engine in it, however there is a problem

basically you can drive the car for a bit (few minutes) fine, with the vtec kicking in as it should, however after that (at a random time) the engine management light will come on, and vtec will no longer engage? other then that the car drives and runs fine

Also once this has happend, you can turn the engine on and off and repeat the same (Vtec will be back for a few minutes till the light comes back up)

what could be causing this? its running with a p28 ECU

any help is appreiciated. Thanks

[thablasta]

Are you low on oil?

[compton]

just checked the oil and its smack bang in the middle of the minimum and maximum mark, and thats parked slope (engine at the top of the slope)

[thablasta]

How big of a slope? The VTEC solenoid is activated off of oil pressure. That's the only reason I ask.

[compton]

its sloped in a sense that, there would be more oil in there if it was on a flat ground, but theres currently half in there

at what point would the lowness of the oil effect the v tec?

[thablasta]

I am not sure how low. I have been down a quart and it still worked. Have you tried swapping out the VTEC solenoid?

[phunhaus]

Diagnose the CEL. THAT'S your problem.

[compton]

how would i go about doing that?

only thing i have tried so far is another ECU (P73) but same issue (dont think vtec kicked in at all though with that). other then that havent tried anything yet

only ever owned vw's and know little about anything else out of the vag range so any help is greatly apprieciated

[phunhaus]

Retrieving CEL codes from OBD1 and OBD2 Civic/Integra

Pics are down currently but you can still read and easily figure out what and where.

[compton]

ok finally figured it out haha. cheers for that

there is a quick flash, then a gap, one long flash then 7 short ones

from what ive gathered this is code 17 - VSS speed sensor?

[SickSi99]

i think that would be 1 and 17. any pause usually means a separate code.

[EKCivicracer]

fill jo oil up holmes

[thablasta]

O2 sensor & VSS, check 'em!

[phunhaus]

VSS makes sense. Without a VSS signal your VTEC won't engage. Also, the O2 and VSS are on the same power circuit from what I remember. The codes are related and point to wiring instead of bad sensors. Check for a short to ground on your power wires going into your VSS.