MarkB

Learn control = disabled
proportional O2 step = lean
Rich/lean flag = lean
loop status = open/went to closed when i revved it
park/neutral = detected
TCC = not locked
pwr str = not high
prom id = 2541
Iac STEPS 57-42
coolant temp = 194.9*
EGR duty cycle 0%
integrator=128
OXY sensor = 194mvolts
manifold air temp = 140*
engine load = 2
block learn = 108
02 cross counts = 24
maf 8grams second
injector pulse= 1.4 ms
at 3k rpm's the egr duty cycle is 40%
oxygen sensor at 4k rpms is 900mvolts
at 3k rpms the engine load is 27
4500 rpms the maf reads 40 grams per second.

i got this info from a scantool, the autoxray

this is from after refreshing the computer and getting rid of the stored codes,and driving into town,which is like a 30 minute drive.

all these were taken with the car at idle,unless specified otherwise.

im having the problem of setting code 32,33,34 when the cars cold,then it runs like *** until its restarted,which even after a minute the ses light goes off and the car runs normal. ANYONE!??

IF yo uneed more info let me know

the cars an 85 iroc lb9 a/4

bigals87z28

EGR and MAF problems eh?

Is that when your car is in closed or open loop? It looks like your EGR is not functioning, and you could be running lean due to no input from MAF.
here is what you do..

disconnect the egr temp switch and then start car and see if you get code 32 again
if you get it again, the wire to the switch shorted or its faulty

if no then you could have a short in the circtry. If its not a short, you could have the very fatal, faulty ecm.

MarkB

the car actually runs very rich.

the problems come up in closed loop when its first started in the morning. then it goes away within a minute or two. the egr duty cycle percentage changes when i rev the motor,that to me means its working? wheres the EGRa temp switch at?

also i dont see how i could have a faulty ecm if it runs fine after a minute ?

rezinn

Definitely MAF problems. EGR isn't going to effect running unless it's leaking.

Does the MAF reading change at all? You might have a new sensor in your future, or at least a new relay.

MarkB

4500 rpms the maf reads 40 grams per second.

yes i noticed it progressivly goes up as i rev the engine ,it was reading about 40 grams a second at 4k to 4500 rpms.

on every morning and the cars totally cold,i get codes 32,33,34

i thought the 85s didnt have maf relays?

bigals87z28

Code 32-
Exhaust Gas Recirculation (EGR) Circut

Code 32 means that the EGR diagnostic switch was closed during start up or that the switch was not detected closed under the following conditions

coolant temps greaterd tehn 176*
EGR duty cycle commanded by the ECM is greater then 48%
TPS less then WOT, but not at idle
codes 21,22,33,34 not present.

and the tep diag. swithc is in teh base of the egr valve.

MarkB

what do you propose i try doing to this thing?

bigals87z28

well, from this service manual, do exactly as i said in my first post.

rezinn

I'm sorry, didn't notice it was an 85. I'm really not familiar with that system. If the MAF readings scale up with rpm, that checks out..but the codes don't look good. Dying/lazy sensor is my only guess.

Morley

It doesn't, it has a MAS module, don't even bother going to GM for one...$$$$$$$$$$$$$.

At that point it would be about $700-$800 cheaper to convert to the 165 ECM.