Scorpio High Idle🙄

[my8950]

Hi all,

I posted this over in the XR section and it is specific to OBD 1 codes:

https://www.therangerstation.com/tech/o ... ord-codes/

The early V6 Ranger used the same engine, as we know.

Hope this helps.

Cheers

I'm not a Scorpio wizard, but I don't think the engines are the same...

[espacef1fan]

As always each time you fix something, disconnect battery and wait a bit and reconnect and re-capture codes to see if you actually addressed the issue.

I think your TPS is bad. Unless you have proven that this particular error code is gone.

One almost never messes with the idle screw on a Scorpio. It is factory set for the life of the vehicle. This is not like a carburetor adjustment.
Why? Because the EECIV controls idle with the idle control solenoid. idle control solenoids can go bad. Mine did.

I’ll be sad if the TPS is bad as I replaced it and the pigtail with the TSB service kit.

I’ve tried several IACs with the same result.

I did try addressing the last possible vacuum leak and made a Egr block off plate.

I’ve ordered a new ECT sensor as it idles normal with that unplugged.

I plan on doing some voltage sweeps of the TPS the next time I fool with it.

[Ed Lijewski]

I totally doubt your new TPS is bad assuming you bought the kit from Merkur Depot or other Merkur vendor. Of course you can do an analog test on it with your MM (just remove from TB) to confirm this.

I'd also examine exposed areas of the wiring harness on the possibility a sensor signal can jump or be muddied crossing into a different wire.

Also with engine running do Ford's Wiggle test: wiggle every sensor connector to see if it produces any changes.

Re the MAP sensor, at least open the vacuum hose and blow it out in case it had moisture in it.

YMMV

[brokencase]

Sorry, I miss-read earlier I thought you had only replaced the TPS connector.

In any case, if you are still getting TPS out of range code then it still points an issue with the TPS, i.e., harness, connection at EECIV etc...

[Ed Lijewski]

replaced IAC with 2.3T IAC, same result

There are differences in some OE IACs.

Dean/Brokencase has posted on this, and posted here on the replacement IAC he bought online for his Scorpio.

YMMV

[Ed Lijewski]

TPS/FIPL Code. "FIPL": Fuel Injection Pump Lever (obviously not equipped on Scorpios).

Recheck for codes using the link posted above.

YMMV

[brokencase]

replaced IAC with 2.3T IAC, same result

There are differences in some OE IACs.

Dean/Brokencase has posted on this, and posted here on the replacement IAC he bought online for his Scorpio.

YMMV

The one I got was not exact replacement for Scorpio but I saw little difference between it and my original.
It worked just fine fine. Standard Motor Products makes an AC20 and an AC22. Both will work.

You can read more detail in that thread
http://forum.merkurclub.com/forum/viewt ... 8&start=45

I think if you get any IAC from late 80's Ford it will probably work OK. It is just a bypass port around the throttle plate that the EECIV controls with a closed loop. The only major transition was when they started putting back emf diodes inside the solenoids.

Symptom of bad IAC in my case was stumble off idle. But my normal idle was OK.

ECT is a possibility, I have seen them fail before.

High idle means the EECIV does not trust something and it is setting the idle high as a limp mode strategy.

[espacef1fan]

Ok so I spent $80 on a factory service manual but the idle speed stop screw adjustment is not in this book

In the troubleshooting tree for code 23 it says to ensure it’s correct before proceeding.

I have in fact messed with the screw so what should I do? Where can I find the procedure?

[Ed Lijewski]

I noted earlier I "think" the throttle plate/butterfly should close fully with no pressure from the accelerator cable. That's what I've observed when I removed the TB for cleanings. So, I'd remove the TB, thoroughly clean it including passages, adjust the stop screw if/as appropriate.

YMMV

[espacef1fan]

I noted earlier I "think" the throttle plate/butterfly should close fully with no pressure from the accelerator cable. That's what I've observed when I removed the TB for cleanings. So, I'd remove the TB, thoroughly clean it including passages, adjust the stop screw if/as appropriate.

YMMV

I just want to be sure it’s undeniably correct before spending any more time troubleshooting as the basis of testing depends on this detail being correct.

[espacef1fan]

Someone please correct me if I’m wrong, but, TPS voltage is measured by putting (+) lead on pin 47(TPS SIG) and (-) lead on pin 46 (SIG RTN)?

[espacef1fan]

Does this pin out look accurate?

[espacef1fan]

SOLVED!

It ended up being that the vref and sigrtn wires were reversed.

It either happened when I replaced the connector or it explains why it was sitting in a field

Now on to dealing with 5-10 yr old gas and making it idle.

[DPDISXR4Ti]

Late to the dance on this one - glad to hear you solved it.

That said, have you pulled the EEC-IV PCM to check the integrity of the capacitors? We should all be doing that. While you've got it out, tell us the catch code. Since switching to the later PCM I have not had a high idle condition.

[espacef1fan]

Late to the dance on this one - glad to hear you solved it.

That said, have you pulled the EEC-IV PCM to check the integrity of the capacitors? We should all be doing that. While you've got it out, tell us the catch code. Since switching to the later PCM I have not had a high idle condition.

I haven’t opened them, not really sure what I’d be looking for .

I have two ECUs now in any case.

I’m assuming the catch code is the ECU code like LA3 /PE etc?