91 240SX KA24DE code 32

[HachiRoku]

just this past weekend while i was driving, my check engine light came on while i was driving on the street at about 45 mph in 5th gear at around 2000 rpm.

after driving for a bit and then stopping somewhere, i shut off the engine and looked under the hood to find nothing visually unusual. i start the engine and the check engine light never went away. after getting on the freeway going at about 65 mph, 5th gear, 2700 rpm the check engine light went away and never came back again.

yesterday, i drove on that part of road where i was getting the check engine light and it came on again until i was on the freeway.

today i took a look at the ecu and it gave me code 32, so i went through the diagnostic procedure for testing the egr function:

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A:the vacuum source to egr control valve had no vacuum at idle.when revving up to 2000 rpm, the vacuum needle jumped up for a little bit and then went back down to 0.

B:voltage test on ECU terminal 105 showed 0 volts for idle and 2000 rpm. (actually 0.6 V)

D:ignition on, voltage from egr & canister control solenoid was at about 12 volts.

E:harness continuity check good between ecu terminal 105 and egr & canister control solenoid

F:inspection of egr & canister control solenoid valve good

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the only test i wasn't able to do was the exhaust gas temperature sensor because i didn't have any tools that would help remove the sensor unless i pulled the header. unless someone knows of a way to get to this sensor without having to pull anything off?

i cleared the error code from the ecu, got 55, went out for a test drive, and it still reports 55. i did not go to that section of road that gave me the check engine light because it is now 50 miles away.

everything seems fine, the car drives as well as it always has been and gas mileage is still about as good as when it came from the factory. can the exhaust gas temp sensor cause diagnostic A and B to fail? all the latter tests seemed to pass.

[NISTECH]

Oh those lovely FSM test procedures...lol

They suck!

reach under your BPT and see if the rubber hose going to it is burnt or has a tiny hole in it. This will cause that code under light accel as you were doing at the lower speed. but on highway driving when the back pressure is higher in the exhust it will be able to over come that little amount of loss and operate the BPT,closing the bleed in the BPT and directing the vaccum to the EGR valve.

[HachiRoku]

found a pretty big hole at the bpt pressure supply hose and got that replaced, so now there's a normal vacuum supply to the egr control valve.

decided to do the voltage test from ecu terminal 105 since it failed and was 0V at idle; at 2000 rpm, it jumped up to 12V and then fell back down to 0V. i'm guessing there may be a leak on a hose connecting to the solenoid?

[NISTECH]

nah ignore that. Fix the hose and drive the car see if your problem is resolved.