87-95 TBI EGR code 32

[jim_in_dorris]

James, I might have over-reacted to you comments earlier, no sweat. It's late here now, but tomorrow after work I will try to get under the hood of my truck and get the part number for an N type EGR, do you need a part number for the solenoid also?

[jameslleary]

Jim,
just the valve would be good, I have the part number for the solenoid as of an hour ago. It would ba wonderful if I could get the egr to work, and still run dual inline magnaflows with the single cat setup.
I also need to look into modding my ecm so I can use the flashable chips....dunno if I have the balls to start de soldering pc boards though!

[jim_in_dorris]

I just got my EGR # off my truck.. What a pita, its upside down on the back bottom side of the EGR as it is mounted. Anyways, I have a 17087196 EGR

The 17087194 = EGV627 says GVW Under 8,500 Lbs.; w/ m.T.

the 17087196 = EGV628 says GVW Under 8,500 Lbs.; w/ a.T.

http://www.summitracing.com/parts/SM...n/?prefilter=1

This looks like the one you need, but rockauto is probably a lot cheaper.

[jameslleary]

Thanks Jim!

[EagleMark]

Did the trucks end up being N? Wondering if cars are P? I've never thought of comparing intakes as that may tell why/if there is a differnce...

[jim_in_dorris]

Mark, almost all TBI trucks are N type.. Apparently they have a low negative pressure exhaust and thus require the N type EGR. Adding dual exhaust makes them even worse.

[EagleMark]

Earlier I had mentioned changing in the bin the MAP ratings to meet qualfiers for Code 32, it's not in the xdf but maybe could be found in hac and added for a simple change.

Today I'm playing with my LT1 and in xdf is this paremeter option "Error 32, Min Diff. MAP Test Value " it is set to 11.88 kpa expecting that much change. But in $42 I think it has a high and low and must be inbetween.

[EagleMark]

Found some interesting EGR stuff in $42 hacs. One mentions Back Pressure EGR?

; 5.7l LD w/Back Pressure EGR (asdx)
;
; This tbl provided a corrected value of
; effective cyl vol/Inj flow rate when EGR
; is active.
; 1. Inj Flow is per bank, in gms/sec
; 2. Cyl vol is liters/cyl
; 3. Ratio = cyl vol/Inj flow
;
; The resulting value is used to predict
; fuel flow using the speed density method.
;
; {During EGR off/on transients the value is
; filtered between the value at LD2B4 and the
; table value for smoothing}
;
; 189.48 = .7125L / 7.713 g/sec TBI
; TBL = 1461.5 * Volume/rate
;=============================================

The other thing is qualifiers that have to be met to enable a code 32 test. Looks like it is not a MAP reading that fails the test but an Integrator count? Several hacs have test fro 30 sec to 90 sec and Integrator change from 4 to 8? So this would be a simple fix so code 32 is still active but fixed to pass test, but if I read this right it could be that fueling is off to begin with because as it closes EGR for test it is looking for Integrator change? Less integrator would pass test easier!

;---------------------------------------------
; ERR 32
; >> EGR <<
;---------------------------------------------
LD52B FCB 90 ; 90 Sec's DIAG CYCLE TIME
;
; ENABLED IF IN MAP WINDOW
;---------------------------------
LD52C FCB 96 ; 45.8 Kpa, LO LD DISABLE
LD52D FCB 208 ; 87.1 Kpa, HI LD DISABLE
;
; ENABLED IF IN TPS WINDOW
;---------------------------------
LD52E FCB 17 ; 6.6% LO TPS LIMIT
LD52F FCB 64 ; 25% HI TPS LIMIT
;---------------------------------
LD530 FCB 250 ; 98% EGR ON THRESH
LD531 FCB 25 ; 2.5 SEC'S EGR ERR DELAY TMR
LD532 FCB 3 ; 3 CNTS FAIL CNT'T THRESH
LD533 FCB 10 ; 3.9% TPS, CHNG TO DISABLE TEST
;---------------------------------
LD534 FCB 28 ; 2.8 Sec's TEST DURRATION
LD535 FCB 4 ; INTIGRATOR CNT LESS FOR EGR FAULT
LD536 FCB 45 ; 45 MPH REQ TO ENABLE TEST
LD537 FCB 255 ; 99.6% EGR D.C, DECREMENT FOR TEST IN WORK
; (Big Blk IS TYP 50%)
;---------------------------------------------

LD52B FCB 15 ; 15 Sec's DIAG CYCLE TIME
;
; ENABLED IF IN MAP WINDOW
;
LD52C FCB 104 ;
LD52D FCB 208 ;
;
; ENABLED IF IN TPS WINDOW
;
LD52E FCB 25 ;
LD52F FCB 64 ;
LD530 FCB 250 ; 98% EGR ON THRESH
LD531 FCB 32 ; 3.2 sec's EGR ERR DELAY TMR
LD532 FCB 2 ; 2 CNTS FAIL CNT'T THRESH
LD533 FCB 10 ; 3.9% TPS, CHNG TO DISABLE TEST
LD534 FCB 30 ; 3.0 Sec's TEST DURRATION
LD535 FCB 8 ; 8 CNT'S, INTIGRATOR DIFF FOR EGR OK
LD536 FCB 30 ; 30 MPH REQ TO ENABLE TEST
LD537 FCB 255 ; 99.6% EGR D.C, DECREMENT FOR TEST IN WORK
; (Big Blk IS TYP 50%)
;-----------------------------------------

[wokeupdead]

I know this is an old thread, did you resolve it? My suburban used to throw that with headers and three inch single exhaust. Egr worked normally, and no light. All about flow.

Edit: Without EGR will probably have nox too high.

Mike

[jameslleary]

Yup, sure did. Replaced the valve with the egv628 mentioned above, and no problems since.

[Tralam]

For anyone who might run across this looking for a solution to their EGR error code (like me), I found a different solution following EagleMarks lead.

I put a vortec 5.7 in my 94 k1500, and used the fancy GMPP intake manifold so that I could keep the EGR for emissions reasons. I would always get a code 32, even though everything seemed to be correct and working. Looking at the $0D hac, I found that the way the test works is by closing the EGR, and keeping track of the Int count. If it increased a certain amount (4 counts) within a time limit (2.5 seconds), the test passes, if not, error 32.
Attachment 10999

I looked at the datalog the moment that the error was thrown, and this is what it looked like.
Attachment 10998
In between the two red vertical lines is where the EGR closed for the test (which failed right after). You can see that the int count (green line) started to increase, but toward the end of the test. Based on the Map (blue line), it looks like the EGR was closing too slow for the test to pass within the time limit.

To remedy this, I modified my XDF to allow me to increase the time limit (I think I increased it to 4 or 5 seconds), and I haven't had an error 32 yet.

[billygraves]

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[SKFengineer]

Billygraves, thanks for your reply... Are you saying that the TCC solenoid could be going bad? I have Code 32 but only when the air temp is between 65 and up. Also to be clear the TCC is the torque converter lock-up, correct?

[1project2many]

Billygraves... I wish I'd heard this back in the dealership days!

[billygraves]

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