A/D vs Temp values...8746 $61
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Joined: Nov 2003
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From: Rockport, TX
Car: 1980 Jeep CJ7
Engine: AMC 360 with GM TBI
Transmission: TF727 set for kill...let's get it on!!!
A/D vs Temp values...8746 $61
Okay, you guys are probably gonna think I am an idiot for trying this, but it works so far. I just need to get the right values in the constants. I already searched and can't find anything to help.
I live in a state that doesn't really have emissions controls, so I don't run an EGR valve. My Edelbrock manifold doesn't even have provisions for one. SO...when I wired the TBI up in the Jeep, I left enough wire coming off of pin A4 for me to be able to tie back into it again to control another relay...for my electric fan. Basically, it fools the ECM into thinking that the EGR solenoid is there when it is actually a fan relay.
I am trying to tweak the EGR On/Off (Temp) constants to cause the ECM to power up the fan at 190F and turn it off at about 177F. I have the table that comes with the A090 definition, but it ranges from -40F (253 a/d counts) to something like 150F (25 a/d counts). Is there an expanded version of this table that includes the approximate a/d counts for the temperature range I am targeting? If not, is there a conversion equation?
TIA!!!
I live in a state that doesn't really have emissions controls, so I don't run an EGR valve. My Edelbrock manifold doesn't even have provisions for one. SO...when I wired the TBI up in the Jeep, I left enough wire coming off of pin A4 for me to be able to tie back into it again to control another relay...for my electric fan. Basically, it fools the ECM into thinking that the EGR solenoid is there when it is actually a fan relay.
I am trying to tweak the EGR On/Off (Temp) constants to cause the ECM to power up the fan at 190F and turn it off at about 177F. I have the table that comes with the A090 definition, but it ranges from -40F (253 a/d counts) to something like 150F (25 a/d counts). Is there an expanded version of this table that includes the approximate a/d counts for the temperature range I am targeting? If not, is there a conversion equation?
TIA!!!
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From: Chasing Electrons
Car: check
Engine: check
Transmission: check
That table should be degrees C not F.
RBob.
RBob.
Code:
;*================================================== ;* ;* Table 1 --- Coolant Temperature, 1k pu ;* ;* ;* A/D degrees A/D ;* counts C Inv ;* ------- ------- --- ;* 255 -40 0 ;* 251 -30 4 ;* 250 -25 5 ;* 247 -20 8 ;* 245 -15 10 ;* 241 -10 14 ;* 237 - 5 18 ;* 231 0 24 ;* 225 5 30 ;* 218 10 37 ;* 209 15 46 ;* 199 20 56 ;* 189 25 66 ;* 177 30 78 ;* 165 35 90 ;* 152 40 103 ;* 139 45 116 ;* 126 50 129 ;* 114 55 141 ;* 102 60 153 ;* 92 65 163 ;* 81 70 174 ;* 72 75 183 ;* 64 80 191 ;* 56 85 199 ;* 50 90 205 ;* 44 95 211 ;* 39 100 216 ;* 34 105 221 ;* 30 110 225 ;* 26 115 229 ;* 23 120 232 ;* 21 125 234 ;* 18 130 237 ;* 16 135 239 ;* 14 140 241 ;* 13 145 242 ;* 12 150 243 ;* 0 200 255 ;* ;*==================================================
Thread Starter
Senior Member
Joined: Nov 2003
Posts: 647
Likes: 0
From: Rockport, TX
Car: 1980 Jeep CJ7
Engine: AMC 360 with GM TBI
Transmission: TF727 set for kill...let's get it on!!!
Got it...you are right about the deg C thing. I just saw that when you said it. I really am an idiot.
Is there a way to take the speed controls out of the EGR control loop by changing constants or is it more involved than that? The temperature control seems to work fine and the ECM is actually running the fan for me, but it doesn't want to run it when I have the engine running. Did I do something wrong or is this not gonna work like I want it to?
Is there a way to take the speed controls out of the EGR control loop by changing constants or is it more involved than that? The temperature control seems to work fine and the ECM is actually running the fan for me, but it doesn't want to run it when I have the engine running. Did I do something wrong or is this not gonna work like I want it to?
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