Bypassed VTEC pressure switch no more codes but wont rev pasr 4,500
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Bypassed VTEC pressure switch no more codes but wont rev pasr 4,500
Hello!
long story short, 1998 accord ex AT 4 cylinder engine, I was getting p1259 and replaced the vtec solenoid and ps assembly. Oil pressure is good, new oil and filter but code would keep on coming on under load (going uphill) and when stepping on the gas pedal in the highway to pass cars so I bypassed the vtec ps and code p1259 is now gone. Car runs fine except when I get to 4,500 rpm's it wil stay steady at those rpm's (no sputtering). No codes come up.
What I did for bypassing the ps was cut power wire to ps and spliced it to the solenoid wire. I left the ps plug connected with the remaining wire.
Also replaced the tps, installed new timing belts and water pump while I was changing the belts because yhe old ones had over 180,000 miles..
I have been reading and searching the web for about a month but can't seem to find a similar scenario.
long story short, 1998 accord ex AT 4 cylinder engine, I was getting p1259 and replaced the vtec solenoid and ps assembly. Oil pressure is good, new oil and filter but code would keep on coming on under load (going uphill) and when stepping on the gas pedal in the highway to pass cars so I bypassed the vtec ps and code p1259 is now gone. Car runs fine except when I get to 4,500 rpm's it wil stay steady at those rpm's (no sputtering). No codes come up.
What I did for bypassing the ps was cut power wire to ps and spliced it to the solenoid wire. I left the ps plug connected with the remaining wire.
Also replaced the tps, installed new timing belts and water pump while I was changing the belts because yhe old ones had over 180,000 miles..
I have been reading and searching the web for about a month but can't seem to find a similar scenario.
MM Gruppe B
Joined: Feb 2009
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From: 94577/Gaillimh
Re: Bypassed VTEC pressure switch no more codes but wont rev pasr 4,500
Your attempt to bypass the oil pressure switch is wrong.
Oil pressure switch is just that a switch, when it closes it then allows activation of the VTEC solenoid.
This is a safety device for the engine, if the sensor is bad it's $10 for a generic one.
Fix your wiring, and replace the oil pressure switch.
VTEC doesn't 'kick in' at a given rpm,it is load specific and can be activated at lower rpm if need be on the F22B1/F23A1/A4.
Oil pressure switch is just that a switch, when it closes it then allows activation of the VTEC solenoid.
This is a safety device for the engine, if the sensor is bad it's $10 for a generic one.
Fix your wiring, and replace the oil pressure switch.
VTEC doesn't 'kick in' at a given rpm,it is load specific and can be activated at lower rpm if need be on the F22B1/F23A1/A4.
Thread Starter
Honda-Tech Member
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Re: Bypassed VTEC pressure switch no more codes but wont rev pasr 4,500
Both Vtec solenoid and pressure switch are new ( Ihave tried everything I have read and searched before posting). Wiring has conectivity all the way to ecu. I basically wired it as if it were a jdm engine (which does not use the PS) with a US ecu. The only issue is that the car does not get passed 4,500 RPM, steady at 4,500 not limiting or sputtering, no codes at all. If I connect it the way it comes from factory I get constant vtec error everytime I drive the car.
MM Gruppe B
Joined: Feb 2009
Posts: 7,027
Likes: 109
From: 94577/Gaillimh
Re: Bypassed VTEC pressure switch no more codes but wont rev pasr 4,500
Do you have an FSM for your car?
P1259 is a combo of system integrity check and engine condition check.
Normally when P1259 activates it is a warning that there is low oil pressure and VTEC will not be activated to prevent engine damage. Thus a 4-4.5K rpm limit.
When you replaced the VTEC solenoid, did you verify the VTEC solenoid valve could be depressed with your finger?
That is the small button that resides under the solenoid.
P1259 is a combo of system integrity check and engine condition check.
Normally when P1259 activates it is a warning that there is low oil pressure and VTEC will not be activated to prevent engine damage. Thus a 4-4.5K rpm limit.
When you replaced the VTEC solenoid, did you verify the VTEC solenoid valve could be depressed with your finger?
That is the small button that resides under the solenoid.
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