MAF Conversion/Idling issues

Disconnect the meter and verify that there's a change. Check TPS. Pull codes. Ensure that BOTH o2 sensors are functional (codes should help with this).

Dump the codes and see what the computer says is wrong…

Here's the link to dump the computer codes with only a jumper wire or paper clip and the check engine light, or test light or voltmeter. I’ve used it for years, and it works great.

See http://www.troublecodes.net/Ford/
OR
See http://www.mustangworks.com/articles/electronics/eec-iv_codes.html

IF your car is an 86-88 stang, you'll have to use the test lamp or voltmeter method. There is no functional check engine light on the 86-88's except possibly the Cali Mass Air cars.

Codes have different answers if the engine is running from the answers that it has when the engine isn't running. It helps a lot to know if you had the engine running when you ran the test.

Trouble codes are either 2 digit or 3 digit, there are no cars that use both 2 digit codes and 3 digit codes.

For those who are intimidated by all the wires & connections, see http://www.actron.com/product_detail.php?pid=16153 for what a typical hand scanner looks like. Normal retail price is about $30 or so at AutoZone or Walmart.

Or for a nicer scanner see http://www.midwayautosupply.com/detailedproductdescription.asp?3829 – It has a 3 digit LCD display so that you don’t have to count flashes or beeps.. Cost is $35.

JRPony said:

I do not believe this to be a mechanical issue as no other work was done to the car other then the aforementioned items. The SD computer idled like a champ when cold and at operationg temp. All connectors are in place and the BAP/MAP vaccum line is plugged. Anybody have ideas?

Click to expand...

I could be completely wrong here, so let me know if I am.

I thought the MAF cars used Barometric pressure not Manifold pressure (actually vac). Only SD uses manifold vac/psi.
If I am correct then disconnecting the BAP/MAP vac line should help your situation.
You could be showing the computer engine vac when it expects to see atmospheric pressure.

Again let me know if I am wrong, as I am just taking a guess here.

The only other thing I can think of is a repinning error, but that should have shown up as a trouble code?

jason

Do you have cruise? What about the VSS? I have done the same swap but I have a Pro-M and I did H/C/I at the same time. I had real issues with the SD when I did it but I didn't want to mess with it so I just converted with the 89 EEC and harness. I have idle issues now when cold but I think my intake needs to be retorked because once warm it idles fine. I hit 2-3 of them that I could get at and they were loose and now the problem has gotten better so I need to pull the upper and do them all in order. Did you change anything else. Once my demons are figured out I'm heading to the dyno shop for a SCT custom chip. I don't have cruise so that code and others that apply will be gone with the chip install.

The vac port on the BAP should be left open, not plugged. It's how the EEC tells what atmoshperic pressure is at startup.