Up & down idle 88 Duke when warm

[Raydar]

According to TunerCat,
$48 supports 87 - 88 Pontiac Fiero 2.5L 4 Cyl. LR8,
87 Grand Am 2.5L 4 Cyl. L68, 
87 - 90 Celebrity, 6000, Cutlass, Ciera, Century 2.5L 4 Cyl. LR8.
A 2.2 is not mentioned.

$70 supports a 90 - 91 Cavalier, Sunbird LM3 2.2L

ECM is 1227748 in both cases. 

What is the file extension for your $48 ? I can look around.
Thinking about it, I'm not sure my TunerCat file will work, though. Since we're doing different things.

[Raydar]

This might be useful...
http://www.gearhead-efi.com/Fuel-Injection/showthread.php?2981-1227748-ECM-Information-48

[Donster]

Can somebody tell me what the second cable to the starter is? It is the thinner one, not the cable from the negative battery terminal.Today I noticed that if I wiggle THAT cable while the engine is running, the idle stumbles and hunts extremely.I never even noticed that cable, I thought that there was only one cable going to the starter?? 

[Raydar]

The only ones I can think of are the heavy red lead that goes to the battery, and a smaller purple lead.
The purple lead is the "start" wire. It will have 12 VDC on it (to pull in the starter Bendix) when you turn the key to start.
If you trace it, it should go to the P/N switch on the trans. It should continue out of the P/N switch as a yellow wire.
Some cars with trunk poppers have a goofy "interlock circuit" that finds ground through that wire, and the starter solenoid. (Strange setup.)

Is it loose? Is the terminal on the solenoid loose?

[Fierofool]

Don, does that extra wire go into a factory wire sheath, or is it free-floating on it's own?  Sounds like they're feeding something off it that they only want to operate while the ignition is ON.   EDIT:  Start position as Raydar said. 

On other starters I have twisted that screw's connection off inside the solenoid when the bottom jam nut was loose. 

[Donster]

Can somebody tell me what the second cable to the starter is? It is the thinner one, not the cable from the negative positive battery terminal.

Of course I meant the POSITIVE terminal.

[Donster]

Don, does that extra wire go into a factory wire sheath, or is it free-floating on it's own?  Sounds like they're feeding something off it that they only want to operate while the ignition is ON. 

Tomorrow I'll have the car up on a lift, so I'll be able to see more. I know the cable disappears into a harness, but I can't tell if the connector or solenoid is loose.

[Donster]

Made no difference. There are 3 cables that go to the starter. One in the rear is ground. Then the 2 in the front are as Steve said, one thick one from alt/battery and a thinner purple wire that goes to the ignition switch. It was a bit gunked up and corroded, so I cleaned all 3 connections and cables but issue persists.

I also figured out that there will only be ground on BLACK12 & WHITE14 if the ECM is plugged in and gets ground on WHITE 12 & 13. (Brain Fart!)
All grounds and voltages on the ECM check out. Hence the confusion earlier; I measured ground at the sensors with the ECM plugged in, so I had ground. Disconnected the ECM and had no ground.................D'uH!

I think I've asked this before; does a bad MAP "always" throw a code?? If I disconnect the MAP cables (not the vacuum), the car idles fine and stable. Unfortunately, it lights up the Check Wallet light and sets code 33 or 34. I plug it back in, the hunting idle returns, but no codes.  

[Donster]

According to TunerCat,
$48 supports 87 - 88 Pontiac Fiero 2.5L 4 Cyl. LR8,
87 Grand Am 2.5L 4 Cyl. L68, 
87 - 90 Celebrity, 6000, Cutlass, Ciera, Century 2.5L 4 Cyl. LR8.
A 2.2 is not mentioned.

$70 supports a 90 - 91 Cavalier, Sunbird LM3 2.2L

ECM is 1227748 in both cases. 

What is the file extension for your $48 ? I can look around.
Thinking about it, I'm not sure my TunerCat file will work, though. Since we're doing different things.

As soon as I load the "so called" $48 file it shows up as:

Fie extension is .xdfAnd when I try to download it from the web, I get a message that my IP is outside the US and I can't continue.Can somebody get the $48 file for me? Please? Pretty Please? 

[TopNotch]

I uploaded the file to http://gafiero.org/files/$48.xdf

[Raydar]

As soon as I load the "so called" $48 file it shows up as:

Fie extension is .xdf And when I try to download it from the web, I get a message that my IP is outside  the US and I can't continue.Can somebody get the $48 file for me? Please? Pretty Please? 

That is clearly the wrong file.
Looks like Pat has got you covered on the correct one. If not, I'll see what I can come up with.

I can believe that a bad map can cause issues without throwing a code. It's just a pressure transducer.

[Fierofool]

Doesn't the MAP sensor also control the fuel pressure regulator, or are they just both connected to the same intake vacuum port? 

[Donster]

I uploaded the file to http://gafiero.org/files/$48.xdf

Awesome! Thanks Pat.
But how do I convert it to an .ads file for TunerPro?

[TopNotch]

Maybe this page will help.

[Donster]

It does help, but also tells me that I need the bin file for the 87-88 Duke.