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Topic: 232 way rich, no power, falls on face (Read 1317 times) previous topic - next topic

232 way rich, no power, falls on face

85 CFI V6.  Absolutely no power.  It's always rich, pulling like 7-10 mpg the last few tanks.  It goes between idling ok and really rough.  Little bit of power at the bottom end, then drops off as you go up RPM, sometimes you get more power again taking it up to WOT.  go to put your foot in it and usually falls on its face so fast it almost feels like a blocked cat. 

Codes:  54  31  24  41  91  31  33  13  77
EVP  / EVR low
IAT High
IAT out of range
system lean
running lean
EVP low
EGR not open  (didn't warm up car pre-test)
Idle Speed Control
no goose test  (didn't bother)

:punchballs:
Am I missing anything obvious?
What do we call the IAT on the CFI system, and where does it live?

How many gallons of Holy Water are we recommended to run in the radiator with the antifreeze?

232 way rich, no power, falls on face

Reply #1
That would be Intake Air Temperature which makes "good good sense" considering its running rich or whatever. If its misjudging the IAT and its out of range then its waaaaaaaay overcompensating for the reading. As for where it is, it should be mounted somewhere in your lower intake manifold. I haven't looked at a CFI v6 in a while but it should be in rear near the cowl. It looks just like the coolant temp sensor on the outside. I believe the wire colors are green/yellow and black.

It could be as simple as the harness not being connected at all or it could mean that you have a bad sensor.
--Steve
[thread=28690]1988 Cougar V6[/thread]
2012 F-150 3.7L
2011 Mustang 3.7L

232 way rich, no power, falls on face

Reply #2
54 Air Charge Temperature Sensor shows -40 degrees
31 EVP EGR Valve Position sensor is too low
24 Air Charge Temperature sensor out of spec
41 Right O2 sensor lean
91 Left O2 sensor lean
33 EGR valve not opening
13 Self test could not reach low idle spec
77 goose
The ACT sensor is called the Manifold Charge Temperature sensor in the diagram.
It has two wires. A black/white wire and a light green/pink wire

 

232 way rich, no power, falls on face

Reply #3
When they go way rich start looking for a big vacuum leak before buying parts.  Especially check the large tube and hose assy that's on the back of the CFI.  Then check all the other vacuum lines.  They break easy.  Once you are sure that there's no leaks then troubleshoot for sensors.  A vacuum leak will force a rich condition.

I learned the hard way.
Armed Forces Car Club
Eastern Sierra Chapter, California
WEB:  armedforcescarclub.com

232 way rich, no power, falls on face

Reply #4
Quote from: tbirdsps;356165
When they go way rich start looking for a big vacuum leak before buying parts.  Especially check the large tube and hose assy that's on the back of the CFI.  Then check all the other vacuum lines.  They break easy.  Once you are sure that there's no leaks then troubleshoot for sensors.  A vacuum leak will force a rich condition.

I learned the hard way.

That's very true. It'll also cause an erratic idle for sure. The MAP sensor line is famous to me for causing  to go wrong in my car.
--Steve
[thread=28690]1988 Cougar V6[/thread]
2012 F-150 3.7L
2011 Mustang 3.7L

232 way rich, no power, falls on face

Reply #5
Was the car warm when you pulled codes? If not you will get the IAT sensor out of range codes.
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

232 way rich, no power, falls on face

Reply #6
update, dropping a new IAT and changing sparkplugs (i'd already picked them up) have given me driveability again!  and my mpg isn't in the 10 and under range.

now I just have to figure out an intermitant miss when warm and at idle.