CPI observations

[j894]

In the past few weeks and months Ive aquired a few extra components
for the 92-95 cpi engine. A few IMTVs and one or two extra EGR valves, etc.
Anyhow it was a nice day out today and i figured what a nice day to
screw around/screw up with my blazer.

I Took off that vortec plenum decoration and unhooked the one imtv and
hooked up one of my extra imtvs to the the electrical connector. I started
the engine, and reved the engine hoping to observe it working. I revved it
and revved it a little hard sometimes and it didnt fokin move. I read its
supposed to open up at 3000rpm (- 4500??) to make a 360* manifold, and
close below 3000rpm to have a 180* manifold. For better low end torque,and
higher end torque. Since I had a second one i "tested" it the same way,
again, it didnt move when I revved it. Still no luck I put one of the extras in
the hole in place of my original one, hooked my original up and revved it still!
nothing, it didnt move? I dont exactly have a tach so i didnt know the
exactly what the rpms were but i revved it pretty hard on all tries and it still
didnt move. So I tried it on 3 different imtvs and not one of them
moved.........

Also I did the same kinda of test with the egr. I hooked up a spare to the
eletrical connector with the original still in place, revved the engine
thsi also didnt move.... theoretically isnt the egr supposed to open at
partial throttle and be closed at idle and full throttle? I did the same thing
again with another spare, with the same result, the valve didnt open..
I didnt take mine off to observe mine. The ses light was out when I tested
each of these... So i guess they wouldnt be bad>? & the valves were not
stuck open/closed with carboin they were clearly clean.


Im i missing something? lol nothing seems to be working but nothing seems
to be wrong?


anyone have input on this or am I an idiot?

[1993blazerlt]

were you in park? I don't know if it will work if it is not in gear. I will check some of my data logs to see if egr works in park

[tunerpike]

The egr will not work in park.

[j894]

ah i see..... does the same go for the IMTV?

[1993blazerlt]

I would guess that it is the same for the IMTV but i can not read that sensor from my computer you might want to try it in N or check the restance of the part and compare it to standard values that is how most sensors are checked of a engine

[Sparky2263]

ECM needs to not only see drive, it also needs to see load to open EGR and IMTV.

John, you getting serious about the CPI finally? Shoot me some mail ;)

[Matt 4.3 TBI]

EGR also needs closed loop flag to operate. Won't work on a cold start, needs to get to operating temp. If you've got a laptop, I'd advise building an ALDL cable and downloading a copy of WinALDL, saves TONS of time troubleshooting.

[bvr775]

that and don't forget some componets use the engine block as a ground...


ewww that thunder is getting close. and we start hurrican season today(hang on florida, it's going to be a bumpy ride)