A9L or 8LD computer, whats what?

[welndmn]

I have run an 8LD for a long, I was wanted to see if I was having some start up issues (my truck runs like crap cold......... not a CTS issue) so I put in my pspare computer.
It happened to be an A9L i noticed my Idel was surging and my Check engine light no longer worked.
What the difference between these 2?
Mine is Mass air motor.

 

[lars]

I have run an 8LD for a long, I was wanted to see if I was having some start up issues (my truck runs like crap cold......... not a CTS issue) so I put in my pspare computer.
It happened to be an A9L i noticed my Idel was surging and my Check engine light no longer worked.
What the difference between these 2?
Mine is Mass air motor.

Mark-

I have start up issues every day, until I get to the coffee pot.

Sorry. An 8LD and an A9L should interchange, apart possibly from some mysterious coding built into the first one since it's a California only mass air computer. My idle surges like mad with any computer I install, but only on warm start-up. In my case it's almost certainly the cam messing with the computer, since the lobe separation angle is less than the computer likes to see (mine is 112 degrees, all stock 5.0 cams are at least 114 degrees.) The cam overlap causes some pulsing in the intake that screws with the mass air meter.

Still, Ford did come out with that air bleed kit to fit between the throttle body and the idle air bypass valve, supposedly to fix otherwise impossible to cure surging problems. I suppose it could be that your A9L is one of the lucky winners that wants to see a bleed valve before it will behave.

Personally I think you need a 408 stroker anyway. Now that your married I'm sure your wife is eager to help pay for it ;D

 

[welndmn]

HA! I got this motor to 280 deg over the weekend (I need to intall a fan control motor) all I though was how a 460 would fit nice in here, or a 427 if my motor ate it.

Anyway, I have a friend with a A9P I am going to try as well. All the surging that was going on was it just idleing in my garage (about 20 mins), I never drove it.
I need to drive it and then pull some codes, but its just strange that the Check engine light woul not work for me with the A9L, but with the 8LD it does work.

I do remember those idle air bypass's, I had one put on my pickup truck, I guess I will pick up one off e-bay, if anything I am just out 20$.
The A9L did make the engine sound better in the 2k+ RPM range.
I am also on the Stock bronco firing order, I never changed my cam . My motor is a 88 mustang motor, but when i built in 97, EFI was a joke so I put a normal HO cam in it.
I bet that A9L will work after a short drive, and if the check engine light no longer works I will somone live another day.