Hi guys, before my engine swap, my brakes never had any problems. Change rotor and pads.. that's it. Since my swap, my brake gets stiff and no brake response. It happened only once in a blue moon before but now it happens 80% of the time. Just to let u know how the pedal feels, it's like when you shut off your engine and just press on your brakes a few times then the brakes gets stiff. Now this problems happens while i'm driving and i lose all brakes. I have to use the hand brakes and lemme tell you that they don't stop the car real quickly. I have changed Brake booster, rotors, pads, calipers, brake fluid to dot-4, Master cylinder and brake hoses. Plz help, I'm all out of ideas. I almost ran into a house coz my brakes died on me at the last minute. I did apologize to the owners for their grass and flowers (also paid them ). This is a problem that come and goes. Tried braking softly and hard. Happens really randomly.

 

You need to check the brake booster, vac lines, check valve, and location where its connected to the IM.

 

He already replaced the brake booster, but yes I would replace the check valve also if you already haven't done so.

 

check the brake booster hose from the im to the booster itself and the check valve also

 

Thanks guys, i'll try the check valve and see if there is any leak. The vacuum hoses from the IM to the Brake booster has been checked. No leaks. Even tried changing the hose but it did not help. I'll let u guys know if the check valve was causing it. Give me 1 day or 2 to see if the problem re-appears.

 

it sounds like a lack of vacuum issue. the brake booster, and the replacement booster stock replacement for the swapped model, or for the current model?

i dont know about interchange ability, but i would look into going with the booster from the swapped model, and hook up the vacuum hoses the way it calls for on that engine.

there could be a difference in the amount of vacuum it makes as compared to the other engine.

make sense?

 

Out of curiosity, what year maxima/altima is your 3.5 out of?

 

Did you happen to tap any vacuums into the brake booster path? I tried that and had the same no brakes result

 

boosters are all the same. been there and done that.

 

Thx guys, the 3.5 came from a 2003 and the Vacuum hose goes from the IM staight to the brake booster. Could it be that the engine might have a problem and is not producing enough vacuum?

 

Doubt that.. make sure that there arent any ports you left freely open on the IM

 

also make sure the check valve is there and operating correctly. stick a vacuum gauge on the line and watch the vacuum in that line. both before and after the check valve would be a good idea.

Do either 3.0 or 3.5 have charge/purge canisters on them for the brake booster? I know the VE uses one for the intake manifold butterflies and stuff, but the brake booster goes directly to the IM with only a check valve. the booster stores the vacuum internally.