Rep Power: 315

Does anybody know how to debug my problem. OBDII scanner is throwing the code P1259 which tanslates to VTEC system malfunction.

My car shakes at idle....could I be misfiring or is it a bad solenoid?
My plugs look good and are correctly gapped.

Any ideas from you honda tech gurus.

Or could you let me know what to fix to get rid of VTEC system malfunction...I deleted the code and have reset the ECU but it made no difference...engine still shakes at idle up to about 1,100 rpms.

The shaking is getting worse.

I know the code has to do with the
Rear VTEC Pressure Switch
VTEC System Malfunction, Rear Bank (Bank 1)

 
Rep Power: 0

i have that same problem. does your vtec work cuse my don't at all well it did for a while but t stopped working i can't go past 4k rpm i should be taking it to the dealership to fix it they said warranty maycover it depeding what it is. i asked if he had any ideas what i could be he said it could be vtec solenoid, ecu, or something else he said it couldn't be the oil pressure cause they don't have that problem here amarillo,tx

 
Rep Power: 0

Make sure the solenoid is plugged in, or that the wire didn't get broken somehow.

 
Rep Power: 380

I had that problem pop up a few weeks ago, went to the dealership and they tested the VTec system... every thing came out normal. they offered to either replace the parts ($130 for parts) or to just reset the CEL and see if it comes back. I opted for the reset. and its only happend once since. So... I dont konw


BTW, the way it pops up on my car is that it will light the CEL and then the car wont rev past 3700 RPMs (Safe Mode). if i turn the car off for about 20 min, the next time I drive the car the CEL will be on, but the car will rev past 3,700 RPMs. If I turn off the car one more time and let it sit.... Either the CEL will be off, or it will turn its self off after being driven for a while. Wierd Eh?

 
Rep Power: 0

Are you running an E-Manage or V-AFC to control VTEC??

 
Rep Power: 323

Check your oil level and make sure it is not low.

 
Rep Power: 315

welll the oil is fine. It does not shut off vtec completely...I have the problem with asnd without the venom vcn 400 turned on. Also my 1/4 lie times have slipped abot 61oths!!!
now I hear a weird nock from the drivers side engine if I let off @ 3K rpms.. nside motor mount maybe?

 
Rep Power: 0

I bet the wiring of the VCN400 is messing with the ECU.

 
Rep Power: 315

I think that it could be misfiring. One of the coils looks a little rusty so I cleaned it and applied dielectric grease to it...it runs a bit better and I found out the nocking noise is caused from the driver side motor mount...the rubber buching has come it half and is being pushed out.

A DMM shows that the wiring of the VCN 400 is fine. I did the DIY VTEC light and it comes on when I drive hard. Also hooked up the LED for the VCN 400 and it shows that it comes on correctly at full throttle.

I am tempted to just fix the motor mount now and trade in my vic for the new Mustang....I can't decide...either Saleen, GT v8 with a supercharger later, or wait till Feb for the Roush Stage 3 or dec 2005 for cobra!! UGH!! tooo many decisions!

 
Rep Power: 315

anyone try the urethane fittings for the motormount with success?

 
Rep Power: 315

bump

 
Rep Power: 452

you still havent fixed this problem after 4 weeks? If you want Pm me and I can go through my service manual and look up the trouble code and give you some steps on what to test and see what the problem is

 
Rep Power: 315

o.k.
anyone else have any ideas?

 
Rep Power: 342

Special Tools Required
-Pressure Gauge Adaptor 07NAJ-P07010A
-A/T Low Pressure Gauge w/panel 07406-0070300
-A/T Pressure Hose 07406-0020201
-A/T Pressure Hose 2,210 mm 07MAJ-PY4011A
-A/T Pressure Adaptor 07MAJ-PY40120
-Oil Pressure Hose 07ZAJ-S5AA200

Step 1) Reset the ECM/PCM

to do this you need to pull a fuse under the hood. Its the No. 6 ECU 15A

pull this fuse for 15 seconds and then reinsert it

Step 2) Check the oil level, and refill is necessary

Step 3) Start the engine, put the car in park if you have an auto, neutral if you have a 5-speed. Hold the RPM's at 3000 RPM until the radiator fan comes on, don't turn off the car just yet.

Step 4) Time to go for a drive, accerlate in first gear to an engine speed over 4000 rpm. Hold the engine speed for at least 2 seconds. If DTC P1259 is not repeated during the first test drive the try this test 2 more times.

Is DTC P1259 indicated?

YES - Go to Step 5
NO - Intermittent failure, system is OK at this time, Check for poor connections or loose terminals at the VTEC solenoid valve, at the VTEC pressure switch, and the ECM/PCM

Step 5) Turn the ignition off

Step 6) Remove the resonator, basically your stock intake is 3 parts, the part right above the throttle body, we'll call this piece A. The middle part that runs from piece A and that extension pipe over by the battery. This middle piece is the piece you want to remove.

Note, im guessing that if you have an aftermarket intake your going to need to put your stock intake back on.

Step 7) Disconnect the VTEC oil pressure switch 2p connector

The rest of the steps will follow shortly

 
Rep Power: 342

Step 8) Check for continuity between the VTEC oil pressure switch p2 connector terminals No 1 and No 2



Is there continunity?

YES - Go to Step 9
NO - Replace the VTEC oil pressure switch

Step 9) Turn the ignition switch to ON (II)

Step 10) Measure the voltage between VTEC oil pressure seitch 2p connector 1 and body ground.



Is there battary voltage

YES - Go to Step 15
NO - Got to Step 11

Step 11) Measure the voltage between the ECM/PCM terminal B9 and body ground



Is there battery voltage?

YES - Repair the open wire between the VTEC oil pressure switch and the ECM/PCM (B9)
NO - Go to Step 12

Step 12) Turn the ignition switch off (II)

Step 13) Disconnect the ECM/PCM connector B (24P)

Step 14) Check the continuity between ECM/PCM connector terminal B9 and body ground.



Is there continuity?

YES - Repair the short in the wire between the VTEC oil pressure switch and the ECM/PCM (B9)
NO - Update the ECM/PCM software if it does not have the latest software, or substitute a known-good ECM/PCM, the recheck. If the symptom/indication goes away with a known-good ECM/PCM, then replace the orginal ECM/PCM.

More to come

 
Rep Power: 342

Step 15) Measure the voltage between VTEC oil pressure switch 2p connector terminals 1 and 2



Is there battery voltage?

YES - Go to Step 16
NO - Repair open wire between the VTEC oil pressure switch and G101.

Step 16) Turn the ignition switch off (II)

Step 17) Disconnect the VTEC soleniod valve 1p connector

Step 18) Check the resistance between VTEC soleniod valve 1p connector and body ground



Is there 14-30 ohms?

YES - Go to Step 19
NO - Replace VTEC solenoid valve

Step 19) Remove the VTEC oil pressure switch (A), and install the special tools as shown, then reinstall the VTEC oil pressure switch



Step 20) Reconnect the VTEC solenoid valve 1p connector and the VTEC oil pressure switch 2p

Step 21) Connect a tachometer

Step 22) Start the engine, put the car in park if you have an auto, neutral if you have a 5-speed. Hold the RPM's at 3000 RPM until the radiator fan comes on, don't turn off the car

Step 23) Check the oil pressure at engine speeds of 1,000, 2,000, and 4,000 rpm. Keep the measuring time as short as possible (less than 1 minute) because the engine is running with no load

[I]Is the oil pressure below 49 kPa (.0 kgf/cm^2, 7 psi)?

YES - Go to Step 24
NO - Inspect the VTEC solenoid valve

 
Rep Power: 342

Step 24) Turn the ignition switch off

Step 25) Disconnect the VTEC solenoid valve 1p connector

Step 26) Attach the battery positive terminal to the VTEC solenoid valve terminal

Step 27) Start the engine and check the oil pressure at 3,000 rpm

Is the oil pressure above 390 kPa(4.0 kgf/cm^2, 57 psi)

YES - Go to Step 28
NO - Inspect the VTEC soleniod valve

Step 28) With the battery positive terminal still connected to the VTEC solenoid valve, measure voltage between ECM/PCM connector terminal B9 and body ground.



Is there battery voltage above 4,000 rpm?

YES - Go to Step 29
NO - Replace the VTEC oil pressure switch

Step 29) Turn the ignition switch off

Step 30) Disconnect the battery positive terminal from the VTEC solenoid valve terminal

Step 31) Disconnect the ECM/PCM connector B (24P)

Step 32) Check the continuity between the ECM/PCM connector terminal B15 and body ground.



Is there continuity?

YES - Repair the short in the wire between the VTEC solenoid valve and the ECM/PCM(B15)
NO - Go to step 33

Step 33) Connect VTEC solenoid valve 1p connector terminal No. 1 to a body ground with a jumper wire



Step 34) Check for continuity between ECM/PCM connector terminal B15 and body ground



Is the continuity?

YES - Update the ECM/PCM software if it does not have the latest software, or substitute a known-good ECM/PCM, the recheck. If the symptom/indication goes away with a known-good ECM/PCM, then replace the orginal ECM/PCM.
NO - Repair open in the wire between the VTEC solenoid valve and the ECM/PCM (B15)

 
Rep Power: 342

If you need further instructions on things like inspecting and/or replacing the VTEC solenoid valve, replacing the ECM/PCM, or anything else, just post here.

 
Rep Power: 0

that should work

 
Rep Power: 0

Wow, good explanation

 
Rep Power: 0

i'll second that!
did you get all that out of the helm manual?

 
Rep Power: 328

that sounds more like a honda tech service manual

 
Rep Power: 342

Bingo



Just sharing the knowledge with my fellow 7thgeners

 
Rep Power: 0

Hey Man Watch Out! thats exactly the same thing that was going on with my car after that safe mode bull **** ....and the noices will only get worse so go get your motor checked out by honda bc that nofo is about to blow just like mine did.....

 
Rep Power: 0

How I can view the pictures of this great post?

Thanks

 
Rep Power: 234

Sorry about the fuzzy pics, phone cam.

 
Rep Power: 313

Moved to 7th gen DIY electrical subforum. This is good information to be here.

 
Rep Power: 0

where can i get one of those books?

I'm having this same issue. I checked the screen on the solenoid but its clear. Everything seems to be hooked up fine. However, i'm ignorant when it comes to checking the electrical connections. Thought about just replacing the solenoid. found a couple on ebay for around $50

 
Rep Power: 234

http://www.helminc.com/helm/product2...C01&itemtype=N

 
Rep Power: 0

Just replace the middle (from the 3) relay under the glove compartment.