Not Another Code 71 Question... (1 Viewer)

[TopGear]

Hi Everyone,
I hesitate to post a new thread about this subject, but as I sit here patiently waiting for my FSM to make it across the Can/US border, I just can't resist asking...

I am troubleshooting a code 71 on my 1992, and I have the VSV out on my bench. I read something like 132,000 ohms across the terminals, which sounds bad. I have applied 12 volts across the two terminals on the vsv (as per Rookie2's post from last May) but do not notice anything happening.
1. Am I doing the right test? (12v across the terminals)
2. What am I looking for after applying the voltage? I assumed the valve should close.

One last newby question..... Would I be better off posting this question as a "reply" to the May 2004 thread from Rookie2, or is a new thread appropriate?

Thanks!
Mark

 

[semlin]

Mark, posting fresh is fine. I have no scanner but do have a 91 and 93 fsm in vancouver so pm me if you urgently need help.

according to the 91 manual to test the vsv you apply voltage across the plug terminals and verify that when you do this you cannot blow air from the nipple at the terminal end out the other nipple (comes out of little barrel thing at right angles). then you disconnect the power and verify you can blow air.

i have to admit the vsv for the 93 looks very similar in the 93 FSM so if you want to try those tests they are the same as for the 91 plus check for 30-34 ohms across the terminals at 20 degrees cellsius, also check for no continuity between either terminal and body,

be glad you have a 92 where the vsv is nice and easy to get at.

 

[TopGear]

Semlin, thanks for the info. That was exactly what I needed. Took the VSV back out (yes it is very easy on a 92) and let it warm up inside to +/- 20 degrees. It is now reading 34.9 ohms! Took it out to the battery and applied 12v across terminal, and it closed just as it is supposed to. Funny that it didn't work that way the first time(s) I tried...maybe it was too cold out?? Will pull the efi fuse and see what happens. Hope my FSM arrives soon. Thanks again!

 

[semlin]

looks like your problem is elsewhere. your code 71 originates from the egr temp sensor attached to the EGR valve. Assuming you have already checked modulator filter, vacuum hoses and ports into the throttle body, I would be guessing carbon blockage in the passage from egr valve to intake chamber. You need the egr gasket to pull the valve and you will probably want the throttle body off as well to clean it from both ends, which requires another gasket.

 

[ChuckD]

I'm trying to test EGR system (after code 71) and part of instructions say to connect port R "to intake manifold". Anyone know WHERE you are supposed to connect this to?
Thanks

 

[semlin]

yes it is confusing. Not sure what motor you have but for an 1fze you need to pull a vaccum hose off a port at the front of the air intake plenum and then connect port R to that port. There are several hoses to choose from. Any one that sucks like crazy when you remove it while engine running will do. you will need a long vacuum hose.

 

[ChuckD]

Thank you. Motor is '94 1fz-fe. Is this vacuum location near the ports P R or E? Another appears to connect to a sensor, one to master cylinder, and then there is a large-ish hose by the sensor? is this it?
thanks

 

[semlin]

no, none of the above I think. Move away from the EGR system completely to the other end of the intake plenum near to the power steering pump. There are a cluster of vacuum hoses there. I have no idea what they do but it does not matter. Just pull one off and attach a hose that will reach Port R.

 

[ChuckD]

Still not sure where this is... looked by pump and some hoses go into intake opposite of the TB. These?
thanks, again

 

[semlin]

ok the EGR modulator and the EGR valve both look like flying saucers, Agreed? Now near the front of the intake plenum is another small flying saucer thing. This is the fuel pump regulator. Use one of the vacuum lines into the fuel pump regulator. make sure it is sucking when the engine is idling.