ECU causing to much retard?
Drifting
Joined: Mar 2005
Posts: 1,923
Likes: 0
From: GA
Originally Posted by CoffeeDrip
How in the world can these wires be grounding themselves out? Through the ECU its self? This would definitly explain why I have no 2 sec FP, constant cooling fan operation( grouning out?), no TPS, IAC voltage, amungst others.
I took the ECU board out of it's case looking for signs of obvious damage & found nothing melted, burned or other wise.
I took the ECU board out of it's case looking for signs of obvious damage & found nothing melted, burned or other wise.
I notice you have an 85...Even with your mods your stock PROM should start and run the car. I swapped out the lil ole 305 in my 85 IROC for a very healthy 350 (cam, TFS heads, headers, SLP runners, Accel base, 24# injectors, etc) and when it came time to start the engine for break-in, ir started up without hesitation and ran like a champ. It did have trouble hot starting but with a PROM programmed for 19# injectors and running 24's that was expected.
Getting a "loaner" ECM may be difficult and a PROM, even more so. Last time I bought a PROM for my 870 ECM it was $44, no idea on price now. BUT! If you can even get a PROM for an 85 F body (TPI) it should start and run the car well enough to verify that yours is bad.
Last edited by Morley; Feb 4, 2006 at 05:47 PM.
Drifting
Joined: Mar 2005
Posts: 1,923
Likes: 0
From: GA
Originally Posted by CoffeeDrip
What is a calpack?
Where in Fla are you? I'm up in Savannah, if not too far I may be able to hook you up with some help & ECM & PROM to try out.
Thread Starter
Racer
Joined: Feb 2004
Posts: 334
Likes: 1
From: Fl
I live down near Naples, Fl about oh about...many hundreds of miles from ya 
Thanks anyway.
I have two different PROM's(stock & thermomaster) & neither makes the slightest bit of difference in the way the car runs. I know the stock prom ran fine before(different ECU), so i'm thinking something on the actual board it's self.
Thanks anyway.
I have two different PROM's(stock & thermomaster) & neither makes the slightest bit of difference in the way the car runs. I know the stock prom ran fine before(different ECU), so i'm thinking something on the actual board it's self.
Race Director
Joined: Jun 1999
Posts: 14,924
Likes: 9
From: Merritt Ils Fl
Hi Coffee, I have an 870 ECM on the shelf. You are welcome to use it if you think it will help. PM me what you want to do.
Are you confident the oil switch behind the distributor is plugged in? If not the fuel pump will not run after the initial pressurization powered by the ECM.
Are you confident the oil switch behind the distributor is plugged in? If not the fuel pump will not run after the initial pressurization powered by the ECM.
Thread Starter
Racer
Joined: Feb 2004
Posts: 334
Likes: 1
From: Fl
You have a spare? Excellent.
The car will start & run, builds fuel pressure & keeps it( the pump runs for 5 seconds after shut off like it should). I will gradually loose pressure to 30psi, but it will just about keep it overnight( it may drop to 20psi).
The ECM doesnt give the 2 second purge in the beginning. I crank the car, in less than a second the pump kicks on & the car fires up, runs for a few & then shuts off. Injector pulse is fine, STRONG spark, & rock solid fuel pressure as of now.
As for the Spark control module. Would this have a say in the actual distributor timing(reason I have to advance it so much to get it to fire) or is it like a on/off switch. I have looked & have no clue on how to test it, nor have a clue as to what it does. Sense knock & retard timing? NO idea. But I am confident it has nothign to do with not giving power to the TPS, CTS, & IAC.
Muffin I am writing a PM now.
Thank you all with the help so far. Even though it isnt running I have learned MUCH about the(even though '85 specific) OBDI & TPI.
The car will start & run, builds fuel pressure & keeps it( the pump runs for 5 seconds after shut off like it should). I will gradually loose pressure to 30psi, but it will just about keep it overnight( it may drop to 20psi).
The ECM doesnt give the 2 second purge in the beginning. I crank the car, in less than a second the pump kicks on & the car fires up, runs for a few & then shuts off. Injector pulse is fine, STRONG spark, & rock solid fuel pressure as of now.
As for the Spark control module. Would this have a say in the actual distributor timing(reason I have to advance it so much to get it to fire) or is it like a on/off switch. I have looked & have no clue on how to test it, nor have a clue as to what it does. Sense knock & retard timing? NO idea. But I am confident it has nothign to do with not giving power to the TPS, CTS, & IAC.
Muffin I am writing a PM now.
Thank you all with the help so far. Even though it isnt running I have learned MUCH about the(even though '85 specific) OBDI & TPI.
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Race Director
Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
Originally Posted by Muffin
Are you confident the oil switch behind the distributor is plugged in? If not the fuel pump will not run after the initial pressurization powered by the ECM.
RACE ON!!!
Thread Starter
Racer
Joined: Feb 2004
Posts: 334
Likes: 1
From: Fl
That is what it does. It wont do the 2 sec, but once it sense that it kicks it on & it fires up.
I just dont get how it wont do the 2 sec, but it will energize after it cranks over(sees power from dist). I am so burnt out on trying to look at the schematic on a 15" screen. I'm used to bigass military T.O.'s this 200 some odd page this is a killer.
I just dont get how it wont do the 2 sec, but it will energize after it cranks over(sees power from dist). I am so burnt out on trying to look at the schematic on a 15" screen. I'm used to bigass military T.O.'s this 200 some odd page this is a killer.
Race Director
Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
Originally Posted by CoffeeDrip
That is what it does. It wont do the 2 sec, but once it sense that it kicks it on & it fires up.
I just dont get how it wont do the 2 sec, but it will energize after it cranks over(sees power from dist). I am so burnt out on trying to look at the schematic on a 15" screen. I'm used to bigass military T.O.'s this 200 some odd page this is a killer.
I just dont get how it wont do the 2 sec, but it will energize after it cranks over(sees power from dist). I am so burnt out on trying to look at the schematic on a 15" screen. I'm used to bigass military T.O.'s this 200 some odd page this is a killer.
The print would be a lot easier to read from your own FSM.
RACE ON!!!
Thread Starter
Racer
Joined: Feb 2004
Posts: 334
Likes: 1
From: Fl
Sorry, I havent been around.
Turns out the ECU was the culprit. New ECU & all is right with the world. Now all's left is some minor tuning.
She will rip them all they way through 2nd. This car will be worthless in the rain.
I side stepped it at 1500(yes only 1500) & the *** end just shot out from the side, tires just spinning.
Turns out the ECU was the culprit. New ECU & all is right with the world. Now all's left is some minor tuning.
She will rip them all they way through 2nd. This car will be worthless in the rain.
I side stepped it at 1500(yes only 1500) & the *** end just shot out from the side, tires just spinning.