fail safety inpection: brake force rear axle insufficient

[eastriver]

:help: Loren

i failed NJ inspection today.

reason:

brake force rear axle insufficient in relation to front axle.

brake force:

left front: 686 lbf, right front: 669lbf

right rear: 240 lbf right rear: 232 lbf

any thoughts on the reason? is this going to be a adjustment thing? or something is broken badly.

the car does feel "pushy" when braking, guess the rear brake is not strong enough.

my question is: is the brake force something adjustable? or this is indication of something needs to be replaced.

i want to get more knowledge before taking the car to dealer on Sat. , but my search didn't find anything useful.

[eastriver]

sorry to mention:

2001 996 cab. tip US-spec.

40K miles.

[1999Porsche911]

sorry to mention:

2001 996 cab. tip US-spec.

40K miles.

Try bleeding the brake system.

[eastriver]

sorry to mention:

2001 996 cab. tip US-spec.

40K miles.

Try bleeding the brake system.

someone in other place suggested the samething.

i go down to check the fluid now. will do it first thing Sat.

thanks

[Loren]

I would flush the brake fluid and then bleed the clutch and brakes.

[eastriver]

I would flush the brake fluid and then bleed the clutch and brakes.

thx loren, that seems to be where the money's at.

i will do it tomorrow and let you know the result.

BTW, do you still have 2001 996 C2 order guide and owner manul pdf? :D

[eastriver]

took to a porsche indy last week.

changed front and rear pads.

bal. 4 wheels.

the car feels much better. the brake has some noise when going slow in traffic, guess it's normal.

but, on my way home, the CEL went on, need to take the car back to the tech.

my cel went on before, and i resetted it in autozone,

P0446 EVAP Canister Shutoff Valve (Function) - Below Lower Limit

i throught it might related to me not shut-off engine when refilling gas.

any thoughts on this CEL?

[Loren]

took to a porsche indy last week.

changed front and rear pads.

bal. 4 wheels.

the car feels much better. the brake has some noise when going slow in traffic, guess it's normal.

but, on my way home, the CEL went on, need to take the car back to the tech.

my cel went on before, and i resetted it in autozone,

P0446 EVAP Canister Shutoff Valve (Function) - Below Lower Limit

i throught it might related to me not shut-off engine when refilling gas.

any thoughts on this CEL?

Could be... if so it should reset itself in the next couple of (driving) days.

[eastriver]

Could be... if so it should reset itself in the next couple of (driving) days.

thanks,

i will go to autozone to reset it one more time, and hope it won't come back! :)

[eastriver]

i pulled the new code today:

P1130 Oxygen sensing adaptation, idle range, bank 2

taking the first error code into considirition, i might have a vacume leak some where. will drive the car next week. if it happens, will take the car to the indy who did my brake.

[Loren]

P1130 Oxygen Sensing Adaptation, Idle Range, Bank 2 – Below Limit

Fuel/air mixture is so rich that sensing is up to its lean threshold.

potential causes:

– Incorrect signal from MAF sensor

– Fuel pressure too high

– Fuel injector leaking

– EVAP canister purge valve open

[eastriver]

P1130 Oxygen Sensing Adaptation, Idle Range, Bank 2 – Below Limit

Fuel/air mixture is so rich that sensing is up to its lean threshold.

potential causes:

– Incorrect signal from MAF sensor

– Fuel pressure too high

– Fuel injector leaking

– EVAP canister purge valve open

thx, loren, and i assume it's ok to drive the car as normal for a few days after i clear the code, right?

[Loren]

As long as the light is not flashing it is okay to drive the car. If the light is flashing that means that you will damage the cats ($$) if you continue to drive.

[eastriver]

As long as the light is not flashing it is okay to drive the car. If the light is flashing that means that you will damage the cats ($$) if you continue to drive.

i bot a small reader ($75) from autozone today, and put it into my grove box, ready to read code any time!

Edited February 19, 2006 by eastriver

[eastriver]

then again,

bad coolant smell came out, looked at my cap, 996.106.447.00

sure enough, time for a new updated cap. :)

Edited February 19, 2006 by eastriver

[Loren]

Both of those codes have at least one potential cause as EVAP canister.

You should never fill the car with it running - it will give a CEL every time. If the gas cap is loose or leaking it will give a CEL. Thank the EPA for that one. If you reseat the gas cap the CEL will clear itself in 2-3 days of normal driving.

[eastriver]

Both of those codes have at least one potential cause as EVAP canister.

You should never fill the car with it running - it will give a CEL every time. If the gas cap is loose or leaking it will give a CEL. Thank the EPA for that one. If you reseat the gas cap the CEL will clear itself in 2-3 days of normal driving.

but did it once won't cause any physical damage to the car, right?

just hard to admit i damage my baby before even take it home :(

i didn't shut off engine cause the car was sitting for 2 weeks before i pick it up, was worrying about the battery.

[Loren]

It should not hurt the car. If the CEL resets itself then the problem has been corrected and everything is meeting specs.

[eastriver]

It should not hurt the car. If the CEL resets itself then the problem has been corrected and everything is meeting specs.

well, i reset them, and hoping for the best!

i used to have bad dream about exam, even though last time i went to classroom was more than 10 years, i might start have dreams about cel now. :D

[wrljet]

well, i reset them, and hoping for the best!

i used to have bad dream about exam, even though last time i went to classroom was more than 10 years, i might start have dreams about cel now. :D

Those nightmares about school exams are very common, and I think I had them for

at least 10 years, but they've gone now.

For 20 years I've had dreams about crashing in VW Busses with insufficient brakes,

or sliding off the road backwards in 914's.

No 996 (bad) dreams yet.

Bill

[wwest]

Why would/does someone think lower braking (torque/HP??) at the rear versus the front is incorrect?

All cars have better, beefier, braking at the front due to the laws of physics. The Porsche has an even greater F/R braking differential since the engine is in the rear vs the front. In the early days all cars had mechanical fluid proportioning valves so the high pressure required at the front did not inadvertently "lock" the rear wheels resulting in a spin-out, loss of control.

These days that function is done, at least on a modern day Porsche, via the skid control ECU functions, sometimes referred to as EBD, electronic brakeforce distribution.

My guess would be that the NJ inspection procedure is wrong.

All vehicles will have lower BHP at the rear vs the front by some ratio but since your Porsche is rear engined that ratio will be somewhat greater than "normal". I'd bet NJ procedures aren't adjusted for rear engine vehicles.

Edited February 22, 2006 by wwest

[eastriver]

in fact, i passed the inspection about a front&rear brake job.

and i don't feel the strong "pushing to front" thing when braking hard any more. i guess, the inspection makes sense, to some degree.

but the P0446 came back last night. will have to make another trip to the shop now. :(

[eastriver]

just some updates.

got my car back last week.

1. cel, P0446,

the valve is bad, replaced, and relaced some vent line too.

part: $277, labor: 282

cel stays off after 700 miles. :-)

2. clunk noise in driver-side front when moving slowly.

bad seal in control arm, had to replaced the whole thing/

part: $300, labor: $153

the car handles better, as the front feels much tighter than before. still not as good as some of the 996/997 i drove before.

so $1000 later, i truely enjoy the car now!

Edited April 7, 2006 by eastriver