EGR stall test question

[zukitrek]

I recently did a manifold gasket change and cleaned everything down there including the EGR passages and valve(but not like a thorough clean) but did not check the EGR mod valve cause car never threw code 51. I assembled the whole thing with new gasket set and started her with good results, idling at 800, good acceleration, in other words everything ok, until I got the dreaded code 51. Before no code, after tune up yes? WTF?

I did my stall test and the RPMs lowered and the car shakes but it never dies? I cleared the code and removed the EGR valve again and cleaned it overnight to get all the carbon buildup out. I then redid the stall test with same results. Car still running fine. Then I got the 51 again. I still need to do the bark test.

Does the stall test is suppose ti kill the engine?

Thanks

[fixkick]

94 16v
the stall test on very strong engines can drop to 400 rpm and shake like a dog. this PERFECT. 180PSI COMPRESSION CAN DO THAT, EASY. AND IS TOP RESULTS. STALLS OR NEAR.

i need to know if car is CAL car ore fed. my guess is both.
the cal (and 94/95) have a EGRT thermprobe in the main valve.
is it plugged in?
is it reading 200k to 300k ohms disconnect (sensor side)


im working on this new page, check it out.
links of egr2a.htm. page, gen 2 kicks.
http://www.fixkick.com/EGR-H3LL.html


on you car, you drive, and the EGR opens off idle.
the sensor gets red hot and goes to like 10k ohms and the ECU looks sees 10k and goes PASSING 51s.
that is all it does. on this car.

my new image
see this?
The B30 egr must be in place and read about 240k ohms cold or and 10k hot. or it will fail.
this is MAin , ALL THERE ARE FOR 16V ON ONE GRAPHIC.

[zukitrek]

You are correct, it has the thermoprobe connected to the the main valve though my car is a 4door?. No have not tested the ohms, I will.
I'll let you if Cal or Fed.

Oh my, there are lots of reading and wrenching ahead!! But I like it.

I'll keep you posted.

Javier

[fixkick]

check the ohms right off, save tons of pain,
see other post next to yours, hes adding the resistor to fool it.
for now.

94 us supposed to have the probe.
many times the probe inside is packed in carbon, and act like a insulation blanket, and fails to see HOT exhaust.
easy fix. clean it.
it reads 200k ohms cold its, just dirty
if infinity ,its blown.

[zukitrek]

So is it safe to remove the probe from the valve to properly clean it?

Javi

[fixkick]

only if it's not seized, if you force it , it will wreck the main body, doubling cost to fix.

if the ohms is right.
it only needs cleaning.
if you have a buddy with a bead or walnut shell blaster, its easy to clean, all as one.
sand blasting is too rough.
id try penetrating oil first and gentle attempts at removal. say about 20foot lbs max.? CCW?
if not , id leave it in place if the ohms test passes.

[zukitrek]

OK. I'm not much of an expert in using a voltmeter, so my question
is Where should the probes touch in the Thermoprobe?

[zukitrek]

Upadte. My RPMs are about 800? but they don fall that much when pulling the diaphragm. (I have pictures of before and after pulling)

Before    

After    

My suspicion is the EGR head passage, cause I did not clean that one (, so bark test is next. I replaced the Mod Valve filter but no other testing on it. The thermoprobe cold test is tonight.

Javier

---

Seeing a new post about the EGR cleaning I did not clean the TB port either. Arghhhh!!

[fixkick]

normal hot rpm is 800 (+- 50)
when you push the diaphram, it drops to 1/2 about 400, and the engine shakes hard, slow and misfires, some stall.
if it does that the exh. paths are open. good.
the dash rpm meter is not too accurate at 400. its not.
i have a video link to the look and sound of a forced EGR at hot idle. (dont hot so the rpm is not screaming cold)
your 2nd photo shows huge drop to me .
the whole point of a stall test, is to avoid a lost weekend of labor , cleaning, 5 major parts, 6 counting the egr main. lots of labor there....

the meter, is easy,. and safe,
see meter to resistance, ohms. if its a non autoranging meter set the scale to. 20k or 200k,
disconnec the thermoprobe 2 pin connector , connect the meter leads to the sensor pins pig tail connnector.
cold it will read 300k or so. if the meter shows infinity on 200k range that is ok, go up one scale, to 2meg range ahh, its 350k. its ok.
then then start engine (2 ways , ill show both)
and push the diaphram by hand (i never do that i use a hand pump. as the dang main is way out of reach) but that is what you do.
you open the diaphram and the DMM meter set to 200k now, you see it drop like a rock, resistance calls as the thing gets hot from exhaust flow.
see that?
or here is one more way. the 1995, many open the EGR parked (1996 you must exceed 2mph to do this)
but if you gun the engine fast does the EGR open by itself. it sure must. The egr VSV opens, the cat back pressure cause the vacuum to reach the egr main. and it opens.
if all that works (total path) hot only the egr is inactive at idle and cold and w.o.t..
if that works the diaphragm opens , racing hot engine, then the DMM drops to like 20k ohms or less, if not the thermoprobe is bad or packed in carbon block.

the thermoprobe is just a resistor. that is heat sensative, called a a NTC Thfermistor. (text book type) the readings of it are in the FSM and on my page,

---

ask questions. its ok.

[zukitrek]

Well mine was not that hot. My wife had driven the car for about 20 minutes and I did the test after 20 minutes of car being turned off.

Is this is the video you refer?

https://www.youtube.com/watch?v=UPO7B7yH43w

Mine does not go that shaky, actually it felt like it corrected the rpm's even with diaphragm pulled. Maybe I should get and hand vacuum if that makes any difference?
But there is not much difference between photo 1 and 2 in needle position, maybe due to not being very hot? Ill try the other test tonight if this nagging cold that got me lets me!! Cheers!!