BP sensor throwing code 22?

[olympic]

I pulled the codes on the SHOpaz today and I got:

code 22-"BP out of self-test range."

I checked the electrical plug and it's secure. And I'm 99% sure the sersor is good as my parts car didn't have a check engine light when I bought it. One thing I'm not sure of is, is this sensor suppose to be hooked up to manifold vaccuum or just left open to atmospheric pressure? When I removed the sensor from my 1989 SHO, it had a strange plastic fitting on the port which would make it impossible to attach a vaccuum hose to. So I just removed the fitting and hooked up a hose that's supplied vaccum by the large port on the back of the manifold. Is this the right way or should this sensor not be attached to manifold vaccuum?

The engine also has a wandering idle which will eventually stall the engine. I checked the TPS voltage and it's 0.745v at idle. I remeber reading in a previous thread that it should be about 0.98v. But when I adjusted the TPS up to 0.9v(highest I could get), the idle went way up. Should I just give the ECM time to re-learn the idle or should I investigate the IAB valve?

Thanks for all replies!

<small>[ April 04, 2002, 08:30 PM: Message edited by: olympic ]</small>

 

[luigisho]

Bryce, I had a similar question on my '90 not long ago. The BAP sensor is for ambient air pressure. The regular taurus of that year had a hose that went to the manifold and therefore was referred to as MAP. The do-hickey where you think a hose would go (on the port) to the manifold is there to prevent just that. I was so bothered by the look of it I had to go to the dealership to be certain.

 

[sdpatt]

For the record, the sensor is called the BAP which stands for "barometric absolute pressure." In other words: the pressure of the atmoshpere. This parameter is needed to be able to determine the density of the air. The MAF sensor measures the mass and from the known volume of one cylinder, the EEC can determine the amount of oxygen in there so it knows how long to leave the fuel injector open. Kinda neat, huh?

 

[olympic]

Ok, thanks guys. I figured that's what my problem was but I wanted to know for sure. I'll unhook the vaccuum line from the BAP and pull the codes again. Maybe that'll cure the wandering idle as well. Gotta get this thing running properly for the trip to the muffler shop! I made a set of SFC's and they'll be welded in at the same time. Check out the pics below.

Any ideas on the TPS voltage? I'm sure it's right but I'm just wondering about the 0.98v reccommendation I read about in the other thread. Maybe that's for Gen2's or something.

 

[luigisho]

Sounds about right. I thought just under 1 was the recommendation. Are those sfc's 2 1" spot welded together? Should def. help. Good luck. We're all waiting for the time slips!

 

[Shoman94]

olympic:
Ok, thanks guys. I figured that's what my problem was but I wanted to know for sure. I'll unhook the vaccuum line from the BAP and pull the codes again. Maybe that'll cure the wandering idle as well. Gotta get this thing running properly for the trip to the muffler shop! I made a set of SFC's and they'll be welded in at the same time. Check out the pics below.

Any ideas on the TPS voltage? I'm sure it's right but I'm just wondering about the 0.98v reccommendation I read about in the other thread. Maybe that's for Gen2's or something.

Actually .97volts at idle is the best setting, if you can't reach that then you need to replace your TPS. Disconnect the bettery....depress the brake pedal for a minute then reconnect the battery and start the car. after about 30 seconds, letting the car settle, turn on lights, A/C and rear defrost and let it idle for about 5minutes. Then your good to go.
Good luck!

 

[olympic]

luigisho:
Are those sfc's 2 1" spot welded together? Should def. help.

Yep, I have an arc welder so I made them myself. I'll let the muffler shop MIG weld them onto the frame.

Actually .97volts at idle is the best setting, if you can't reach that then you need to replace your TPS.

I tested the TPS from throttle closed to WOT and noticed nothing unusual in the voltage output. I loosened the screws and adjusted it up to about 0.9v which awas as far as it would go. But when I did, the idle went way above normal which makes me think the 0.745v setting is correct for the ECM. I'll fix the BAP problem and let the ECM relearn the idle(as you described) and see what happens.