Thankyou for the changes i will burn it to a chip and try driving it some more, and record some more data and see how it reacts. By the way it was failing for hi CO and real high HC,
Thankyou for the changes i will burn it to a chip and try driving it some more, and record some more data and see how it reacts. By the way it was failing for hi CO and real high HC,
OK I burned the file on to a 27sf512 chip and pop it into my modified ecm that i socketed with the end 2 pins on each side connected to pin 26. I turn on the key and the check engine light just flashes fast. The truck does start and run though. I did some more research as how to burn the 27sf512 for this application and it would seem that i burned the program to the wrong area of the chip so i burned another with an offset of 00F000 which put the bin at the end of the chip. I inserted the new chip in the ecm, same thing CEL fast flash but runs. so i put the original ECM in and the original prom and the CEL still flashes fast. Anyone experienced this? also i can not connect to it now with a scanner or my aldl cable.
Also i checked out the distributor and ignition module and it is hooked up to control timing however the reference low from the ign module is connected to ground and the pin on the ecm is not connected to anything, Is this a problem? Also the distributor still has mechanical advance. The Mechanical adv should be locked down so that it cant advance the timing correct? Another thing, it has no VSS input.
Last edited by autoekim; 07-06-2014 at 04:39 AM.
I guess i had put the wrong prom in the original cause i found another one and it works normal so what could i have done wrong with the 27sf512 chip?
Last edited by autoekim; 07-07-2014 at 02:41 AM.
Well i removed the modification from the socket and made it to the chip itself and now it is working. While i was working on the scout last weekend i discovered that the distributor did not have the mech adv locked down, so i welded the weights down. Also i found a vacuum line that went to the passenger side valve cover to the intake. it is not the PCV tho because the pcv is in the intake at the rear of the motor correct? I removed the vacuum line from the valve cover from what looks like a crankcase vent. after doing this it does not want to idle very well it only wants to idle at 550 to 600 rpm's after it is warmed up. Sometimes it just dies. Should i raise the idle in the bin, or try to set a base idle on the throttle body. I am not sure what the proper thing to do is. Also i am using the ftdi rl232 chip for my data logging and i am getting errors, it appears that the connection is not stable is there something i can do to improve this?
The PCV is supposed to come from the grommet off the valley pan to carb, or in TBI case front of TBI. The line from valve cover to air cleaner is the breather. You must have a breather or you will suck all your gaskets in... or first one that fails...
Idle RPM is set in bin, throttle plates are for min air only. The IAC controls Idle RPM through ECM.
1990 Chevy Suburban 5.7L Auto ECM 1227747 $42!
1998 Chevy Silverado 5.7L Vortec 0411 Swap to RoadRunner!
-= =-
Thank you Eaglemark. I believe i found my connection stability problem also, I was using a cheap inverter on my laptop.
I am newby too. I was wondering which IH engine you are working on, its it the slant 4 or a V8? I have been following along learning from your tinkering. -Dave
345ci v8
I have decided to cough up some dough and ordered a Moates autoprom setup. It is supposed to be here on monday. I am hoping that i can spend more time tuning and less time trying to make my equipment homebrew crap work. I will continue to post here and let you all know how it is going. There is a lot of good info on tuning on the Moates website. So its time to hit the learning material and see if i can keep from turning this Scout into a pile of molten slag!
Well i haven't had time to play with the scout but did get to set up a 95 LT1 motor in a 92 camero. The Autoprom worked flawlessly. I also hooked it up to the scout last night it also hooked up easaly and worked the first time. didn't get a chance to play with it at all, it was late. More to come later.
well got it all running good except it has a surging idle out of gear, in gear it is fine any ideas?
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