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MAP? BAP???

  • Thread starter Thread starter SetofAces
  • Start date Start date May 22, 2009
S

SetofAces

New Member
Jan 22, 2009
103
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0
SF Bay Area
May 22, 2009
#1
  • May 22, 2009
  • #1
So I'm finally getting close to firing my motor (I hope . . . I hope I hope I hope . . .); I've already got the cam in, front accessories on, "upgraded" heads (e7s vs. the e6s that were on it) etc, and I'm working on getting my exploder manifold ready to put on, when I was looking at my MAP sensor and realized that I'd forgotten about it.

Yes, that's right, MAP sensor, not BAP sensor; I searched the part number and it came up as being a MAP sensor for a 1990 crown vic (so I guess I finally know exactly what non-HO motor I have).

The interesting thing is that I hooked up a scanner before I ever started the h/c/i swap, and the computer was throwing a code for the MAP sensor not reading anything; this is interesting because I have an A9L (or A9P, whichever is the automatic, I forget) in my 5speed. I know having an auto computer is actually a slight advantage in a 5spd, but if my car is supposed to have a BAP, why would the computer throw a code for the BAP? Or is it the same code? I don't know, I had someone helping me and he told me the code was for a MAP sensor. I hooked up the sensor to the manifold, but noticed no real change in how the car was running (like crap, because the SFI computer was trying to run the HO firing order on my non-HO motor) and I never checked to see if the code cleared, and the CEL was still on (clutch engagement sensor is out, but who cares).

At any rate, will this make a big difference in how the car runs? Or should I try and find myself a BAP sensor at the junkyard?

BTW I almost can't sleep, I miss my car so much and I can't wait for my new 100+ hp over what I had . . .
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
34
129
May 22, 2009
#2
  • May 22, 2009
  • #2
The MAP and BAP can be interchanged.

A clutch switch should not cause a CEL.
 

SabinStangs

New Member
May 21, 2009
8
0
2
North Cackalacky
May 22, 2009
#3
  • May 22, 2009
  • #3
On a mass air car the BAP (MAP) sensor should not be hooked to vacuum. The port should be left to open air to read the barometric pressure.
 
S

SetofAces

New Member
Jan 22, 2009
103
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0
SF Bay Area
May 22, 2009
#4
  • May 22, 2009
  • #4
While a MAP and BAP essentially do the same thing, the MAP I thought has to be hooked up to manifold vacuum (unlike a BAP); and I do have a MAP apparently . . . should I swap this for a BAP? Or are they really the same thing? If so, then I probably have to replace it (because of the code) . . . but now I can't remember if it was active in the computer, or stored; but with the CEL on, I suppose it must be bad (or not hooked up to vacuum as it should be) if the clutch switch really doesn't turn on the CEL, but why wouldn't the clutch switch turn on the CEL if the code for it is in the computer??
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
34
129
May 22, 2009
#5
  • May 22, 2009
  • #5
As said already, since you run an A9P you need to leave the BAP vac port vented to atmosphere.

If you've been playing around with the vac line attachment to the BAP/MAP while the car runs, that can generate the code.

Are we to assume you got a code 67? Be sure the car is in neutral and the AC is turned off. This code has to do with engine loads and how it would invalidate operating tests.
 
S

SetofAces

New Member
Jan 22, 2009
103
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0
SF Bay Area
May 23, 2009
#6
  • May 23, 2009
  • #6
Oh I'm so close to getting her running . . . I salivate at the thought . . . of discovering all of my mistakes in my build lol [knocking on wood]
 
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