Me and a buddy were thinking bout taking to EGR vavle of our cars he has a 83 Mustang Gt but it doesn't have OBD1 if I do this will it throw a code if I do the EGR valve deleate I know on OBD2 it will but on OBD1 will it.
yes, it will unless you have a tuner turn it off through a chip.
Not sure about a 2.3 ECU, but the product listed on the website below will work for EGR bypass on a 5.0 ECU. I would guess the electrical stuff can be used for the ECU.
http://rjminjectiontech.com/?p=9
The 2.3L cars always throw an "Insufficient EGR flow" code due to the restricter they put in the line during the recall. That's the only code you will get.
AFAIK if you remove the EGR it will throw a code but the EEC will compensate for that by removing the EGR function from it's calculations for fuel and spark resulting in no loss of drive-ability. It will throw a code but run fine. This is according to Joel5.0 on sbftech.com
Excuse me if I'm wrong-but aren't 83 mustang gt's carbed with no computer?
My EGR is deleted
Check engine light on thoughing code that’s it
Engine runs fine
So what's it hurting??? I may run a off road pipe, but the EGR still functions...
The EGR is the only emissions component left on my T-bird. It helps with part throttle fuel economy and doesn't hurt performance so I left it on. It's off at WOT so it's not hurting anything. Really I don't know why someone would want to disconect it....
Thanks guys. The mustang still has a code devise its the one before OBD what ever that is.
Is that site the top dog of wiring harnesses ? I never knew all the little issues with different companies until i read through all that. You recommend these products?
It ain't nuthin' but a resistor... Value I dunno...
yeah, thats what i was thinking,, they are calling out .5vdc,,, so whatever the EVP reads in its rest position would be the resistor size.
Would be easy enough to measure... If I remember correctly, the total resistance for the sensor is 4.5K ohms...
If all this is true, could just plug the vac to the sensor to test... I'm thinking it will set off the CEL, once engine is up to temp and cursing at speed...
double post
Readings from my EGR valve position sensor:
Reference voltage: 5.07v
Total resistance of the sensor pot: 4300 ohms
Signal voltage to signal return(gnd) at KOEO: 1.06v
Current from voltage ref to sig return:
I=E/R, 5.07/4300=.00118 amps
Resistance between sensor signal(pot wiper) and sig rtn(gnd):
R=E/I, 1.06/.00118=847.5 ohms
Resistance between sensor signal and reference voltage:
R=E/I, 4.01/.00118=3398.3 ohms
So you would need two resistors, an 850 ohm and a 3400 ohm.
Hook the resistors in series with the 3400 ohms to the 5v and the 850 ohm to sig rtn(gnd). Sensor signal hooks between the resistors.
This would prevent KOEO codes but you still would get KOER codes.
My sensor signal goes up to 1.56 volts running KOER tests. I don't know if that's the max under running conditions or not.
Since CEL only happens when running. maybe redoing the math with the higher signal voltage would prevent a CEL.
Of course you would have to live with a KOEO code.
For 1982 & 1983 there was a 2.3 Turbo option on the Mustang GT
Brent
:cougarsmily:
Those values are both odd values, when dealing with general replacement resistors... A 3300 is common and should be OK, closest to a 850 would be 820... If it gives a problem would be easy enough to add a 27 ohm in series with it... In precision 1% tolerance resistors, there should be close values avail, but you ain't gonna find them at Radio Shack...
I suppose you could find a pot with a similar total resistance and just set it to what ever works.
Yup probably the best idea, a common 5K pot would likely be fine... Just set the signal return voltage and forget it... I'm still thinking it will trip the CEL when the EEC doesn't see a voltage change at cruse speeds... Mine works fine, ain't going to mess with it...
That was Canada only. I wouldn't mind having one......
Bigger fish to fry though ;)
That is true, in Canada the 2.3 Turbo engine was optional engine on the Mustang GT.
Here in the states, it was marketed as a separate model called the Turbo GT.
Pretty neat car, but personally I would much rather have an '84 Capri Turbo RS. :D
Brent
:cougarsmily:
I was unaware of that. Thought that the first U.S. 2.3t Mustang was '84.....
There is a benefit to EGR. It lowers the combustion chamber temperatures and reduces pinging which can be a problem with high temps and aluminum heads.
Not sure if this is what your looking for, but I've used this at the EGR position sensor to eliminate annoying codes on a couple of my modded Mustangs, so it should work for us.
(http://farm4.static.flickr.com/3100/2872846768_517880754f_o.gif)
What does the resister between VREF and EVP do for you? I can't see where it would have any affect on the SIG RTN voltage.
I doesn't, but it more than doubles the amount of current drawn by the circuit(VREF & EVP)... Looks as some one designed the circuit that didn't really know what he was doing...
Well they may not of known what they were doing... but it kept the computer happy and didn't hurt any electrical circuit for over 2 years. There's probably a more efficient way, so let us know.
I have no doubt that it works. I thought maybe you were the circuit designer and could teach me something.
Not me, I'm really good at tearing into electronics, not designing them. Though I do know from experience that electrical engineers put just so much smoke into computer chips. If you let some of it out they never work again :D Since the design seemed to be wrong to Turbocoupe50 he might be able to come up with something better.
edit - this worked for me, but you may search some Mustang boards also for a possibly better work around.
I stared at the drawing and considered redrawing it and then decided its probably just a mistake. the second black resistor was messing with my head but then keeping it simple, the path of least riesitance still proves out.
It probably works fine but ill bet it works fine as well without the second resistor softtouch pointed out.
Yes it should...
As I stated, it's doubling current flow between VREF & EVP... Circuit now has two current paths, one directly through the 3.9K and the second through the 3.9K & 390 ohm(the resistance of the pair is similar to the sensor)... In reality this probably won't cause a problem, as there is a current limiting circuit(resistor) in the EEC, to protect it in case of a wiring short in the harness...
If the circuit doesn't work without the "direct" 3.9K, the ratio between the 390 and 3.9 in series may not be optimum(possibly would need a value for the 390 from 430 to 510 ohms), not familiar with the current limiter circuit inside the EEC...