Hi Guys,

So, in the last week I lowered my 07 G35X on Eibach prokits, cleaned the rear brakes, and redid the front brakes (new rotors, pads, and SS lines). I drove it to work yesterday but the brakes were very spongy due to trapped air. I bled the brakes in the FSM-recommended X pattern this morning and now brake feel is superb, like a brand new G37.

My problem now is that since bleeding them this morning my brakes lights stay on even when I'm not pushing the brake pedal. Also, while I can rev the engine in Park, when I shift into Drive the car goes into super-limp mode and I can't rev it or get above about 20mph. Also, after a minute or two of driving the VDC, Slip, and ABS lights come on. I've had this happen (the lights, NOT the super-limp mode) before but the brake fluid was low, however it's right at the MAX line in the reservoir.

Any ideas?? Thanks guys.

 

IDK if this may have any bearing on what you're experiencing, but I've seen other cars have issues with air in the ABS system. Since you drove it with air in the system, it is possible you may have gotten air into the ABS pumps. When air gets in there, I don't think you can purge it via normal bleeding methods. Can't say for Infiniti, but I know BMW uses a computer diagnostic routine to cycle the ABS while bleeding it. I was successfully able to bypass that ($$$) step by just driving the car in a remote area and fully activating the ABS a number of times in succession (to push any air through the pumps and into the general system lines. Then, a quick re-bleed on all fours and I was done. Another thing or two you may wish to look into is whether or not you may have damaged/disconnected/interfered with the operation of a wheel speed sensor, OR if you may possibly need to re-adjust your "brake pedal depressed" switch. The limp mode makes me think of the switch because I know the car will throw all those lights and enter limp mode if it thinks you are trying to drive with the brake pedal applied. Good luck, and let us know what it turns out to be.

 

this is what i was thinkin but i dunno

 

A guy at work told me the same thing about the switch... I'm going out to the garage to look at that now. Hoping I don't need to disassemble much to get to that though. The FSM shows some diagrams but they aren't exactly photos of what to look for

 

K, it's definitely the switches above the brake pedal.
- Normally I have to push in the brake pedal to start the car- I don't have to do that right now.
- When I pull up on the brake pedal and engage those two switches the brake lights go off
- When I pull up on the brake pedal with my foot while driving, the engine will accelerate again.

So now I just need to adjust the brake pedal a smidge higher so that it's back to normal... Any tips on that? The FSM tells you the exact mm to adjust to but doesn't exactly impart any practical knowledge for doing that =-) Starting to search for a DIY on adjusting the brake pedal..

Or maybe I should just stop breaking things and drive in to a shop somewhere close by.

 

That's actually very good news. It shouldn't be too difficult to make the adjustment. Have you gotten down there to look at it? I haven't done it myself on a G, but I have on others. I would look for an adjustment to move the switch rather than to move the pedal, unless the pedal has a great deal of free play up and down. I think once you get into it it will become fairly evident what you need to do. Good Luck!

 

The pedal has a little bit of free play- maybe less than a centimeter. The switch on the left has some plastic tabs but I can't get it to disengage and pop up with needlenose pliers, and the one on the right does have an adjusting nut. Interestingly if I push up on the plastic bumpers connected to the pedal in rest position then they'll engage both switches.

Anyway thanks for help- gonna keep fiddling with it and texted a local guy to help. No way I'm gonna let the stealership rake me over the coals for $200 to turn a wrench.

 

Update: Wasn't able to figure it out, but the local nissan dealership (not the infiniti one, money-grubbing b@5turds) only charged me $110 to power-bleed by brakes with my fluid, with a promise that that would fix it.. they bled it 3 times to get all the air out, then went in and adjusted the clearances on the brake pedal switches afterwards anyway. Basically almost a full day of labor for all that. Still don't know how to fix that myself but everything's working great now. Thanks guys for all the advice and leading me in the right direction... hope nobody else runs into this.

 

Can you post a link to this? I want to install SS lines and want to know the right way to bleed the brakes on our car. Thank you

 

From the '07 FSM:

Bleeding Brake System INFOID:0000000000958408

CAUTION:
• Turn the ignition switch OFF and disconnect the ABS actuator and electric unit (control unit) connector
or the battery negative terminal before performing the work.
• Monitor the fluid level in the reservoir tank while performing the air bleeding
• Always use new brake fluid for refilling. Never reuse the drained brake fluid.
1. Connect a vinyl tube to the bleeder valve of the rear right brake.
2. Fully depress the brake pedal 4 to 5 times.
3. Loosen the bleeder valve and bleed air with the brake pedal depressed, and then quickly tighten the
bleeder valve.
4. Repeat steps 2 and 3 until all of the air is out of the brake line.
5. Tighten the bleeder valve to the specified torque. Refer to BR-41, "BRAKE CALIPER ASSEMBLY (1 PISTON
TYPE) : Exploded View" [front disc brake (1 piston type)], BR-45, "BRAKE CALIPER ASSEMBLY (2
PISTON TYPE) : Exploded View" [front disc brake (2 piston type), BR-52, "BRAKE CALIPER ASSEMBLY
(FRONT CALIPER 1 PISTON TYPE) : Exploded View" [rear disc brake (front caliper 1 piston type)], BR-
56, "BRAKE CALIPER ASSEMBLY (FRONT CALIPER 2 PISTON TYPE) : Exploded View" [rear disc
brake (front caliper 2 piston type)].
6. Perform steps 1 to 5 for the rear right brake → front left brake → rear left brake → and front right brake in
order.
7. Check that the fluid level in the reservoir tank is within the specified range after air bleeding. Refer to BR-
11, "Inspection".
8. Check each item of brake pedal. Adjust it if the measurement value is not the standard. Refer to BR-7,
"Inspection and Adjustment".