Codes, the cold, and a blown gasket.

Topic: Codes, the cold, and a blown gasket. (Read 1385 times) previous topic - next topic

Codes, the cold, and a blown gasket.

October 28, 2014, 06:19:04 PM

Hey folks! Newbie to the forums - lurking since the lady and I got ourselves an '88 3.8 'Bird a couple years ago. Fell in love with the 1956 birds when I was a kid and learned to love the fox when it fell in our laps (that, and we were down to an '83 E250 7.5L 460 punching a massive hole in our minuscule savings as a daily driver following the untimely death of our :barf: Neon.)
Well, she blew a head gasket last week. The Thunderbird is a bit of an heirloom (her uncle is OO) and she's in great shape mechanically (despite the rusted roof and the destroyed interior. She had a full rebuild at the dealership 15-20 years ago.), so we thought it'd be worth saving.

It's back on the road now and didn't fight us too hard to get it there, but she's not quite herself. When it's cold, she just can't get up and go. She has no power, backfires if you try to gas it too hard, and just doesn't want to talk to anybody until she's had her coffee. Once everything's nice and warm and the thermostat opens up, she's mostly groovy. She hesitates a bit, but I suspect I missed a vacuum somewhere, as I have a lonely nipple on the rigid line from the PCV valve to the upper intake manifold. Do these 3.8s usually have a double port PCV valve?

EEC is throwing code 51 and code 54 on KOEO.
I've replaced the coolant temperature switch and cleared the codes (I think), and she's still throwing 51.
I'm also not quite sure what an air charge temperature sensor is, if I have one or where it is, or how it differs from the intake air temp sensor. The ACT and ECTS look really similar in appearance - have the same round/square-corner electrical connectors but one's terminals is rotated 90degrees from the other, and the ACT's thermistor is exposed while ECTS's is not. Not sure if wrong part, or Ford changed the connector...
Any info would be greatly appreciated!

tl;dr : car runs py cold. code 51 & 54 KOEO. New therm switch, still 51 and 54. Not sure what/where ACT is, is it this thing on the front passenger side of the lower intake manifold? They look a lot alike and threads fit, but I'd need to replace the electrical connector to plug in ACT.

Thanks!

Codes, the cold, and a blown gasket.

Reply #1 – October 28, 2014, 06:32:49 PM

Codes 51 and 54 are for the ECT and ACT respectively. These codes will generally pop when you run a KOEO test without having first gotten the car to operating temperature by running it first.

If you ran the test with the car cold these will usually pop up. The ACT will show up almost 100% of the time in that situation. The ECT depends... At least that's my experience with them....

The part you are describing sounds as if it is in fact the ACT sensor.

Codes, the cold, and a blown gasket.

Reply #2 – October 28, 2014, 07:07:42 PM

Gotcha, thanks V8Demon. New to EEC, guess I need to read the quick test procedure a little better.

I did find the ACT sensor milling around just now, rear center of the lower manifold. I'll assume for now that the other part on the front of the manifold is another coolant sensor. They just look so darn similar I wasn't sure. I had some experiences with my Chrysler Cordoba that required changing out a few connectors because DC decided to change things up.

Now that I've that ACT plugged in :hick:, I'll clear the codes and drive 'er around some tonight, see where I'm at...

Codes, the cold, and a blown gasket.

Reply #3 – October 29, 2014, 05:07:36 PM

Well, don't I feel stupid. Three connectors for two temp sensors. Simply had the wrong one unplugged. She's running like a champ now.

Codes, the cold, and a blown gasket.

Reply #4 – October 29, 2014, 07:45:33 PM

Better something silly than something expensive. Glad you found it

Codes, the cold, and a blown gasket.

Reply #5 – October 30, 2014, 12:16:10 AM

Amen to that.

My heart has certainly grown fonder of this vehicle now that it's functioning properly. Also now much more confident in putting more work into the aesthetics and non essential systems now that we know the shape of the engine. The lady and her car are both very happy. Thanks again!