I have error code 1237, which has something to do with the sensors anybody know more? I'm taking the car to the dealer but the manual did not have a lot on it. Anyone with a better manual?

 

1237 is "Secondary Upstream Manifold Air Pressure Sensor Low Input" Hope you know what that means, I have no clue ? ? ??

Good Luck

 

It's most likely a faulty T-Map sensor. The sensor runs about 40 dollars.

 

Nope, wrong sensor. The TMAP is the other sensor.

 

It's at the dealer now I should know tomorrow.

 

I had read this as well but did not know what the heck it meant.

Thanks

 

The MCS has a sensor between the throttle and the supercharger that measures air pressure. It checks to see how well the supercharger is working, among other things. Some mods, like Ryephix#1 can cause air pressures to fall below the minimum working range. The fault you have indicates that the ECU saw a voltage below the minimum working range for that sensor. The possibilities are:

that your air pressure in that area really was too low
that the sensor is malfunctioning
that the wiring between the sensor and the ecu is malfunctioning
that the ecu is malfunctioning

 

FYI, the factory scan tool should be able to give you the conditions that existed when the fault code was detected. Our scanner found this same code in my car when I tried Ryephix#1

2/23/2005 12:25:08 PM
====================================
Fault Codes Found: 1
----------------------------------------------------------
Fault Code 0x1237 (4663)
SECONDARY UPSTREAM MANIFOLD AIR PRESSURE SENSOR LOW INPUT
----------------------------------------------------------
Short to Ground
Sporadic Error - Repair Sporadic Immediately !
Warning Lamp State
Fault Code Count 31
Distance Since Last MIL, DBW, or EP 4.20Km
Intake Manifold Absolute Pressure 176.48 hPa
Upstream Manifold Pressure 109.97 hPa
Throttle Opening 0.47 TPS Deg
Engine Speed 2795.00 rpm

----------------------------------------------------------

 

Are you saying here that the 2ndary MAP sensor has an output voltage during normal operation that's above zero, even when there is significant vacuum (like under strong engine braking)? If that's the case, then how low would the pressure need to be to cause that sensor to be out of range?

It seems more likely to me that the sensor or the wiring is bad -- maybe pulled loose or rubbed off some insulation during some of the mod activities -- sounds like the dealer is trying to milk him for a new ECU.

Is there any easy test with a DVM or such that could validate quickly that the sensor is generating a valid signal or not?

 

I looked up in the comprehensive list of DTC codes for the MCS and found that there are several distinct codes that indicate problems with the secondary MAP sensor. Given this list of variations on the problem (and making the assumption that the MINI ECU can correctly generate these codes) I would say that P1237 that you're seeing looks awfully like a short to ground on the wiring going to that sensor, or possibly a bad sensor.

I don't mean to harp on this so much but I've spent my share of time with the code scanner on my car and have found that there are lots of places where you might have a loose connection or the possiblity of rubbing along the wire path.

<DIGRESS>
Heck, the whole thing may be disconnected accidentally. I had this same thing happen with the coil pack a few weeks ago -- I was uninstalling my Alta Intake in preparation for selling my car. The next day I was driving down the highway @ 65MPH and had an EML/SES condition that basically killed the car right there and then. I had the car towed back to the house and whipped out the scanner. I was getting the following codes:

P2300 8960 Ignition Coil 'A' Primary Control Circuit Low
P2303 8963 Ignition Coil 'B' Primary Control Circuit Low

My first thought was that the coilpack had somehow died, but after retracing my steps I found a connector -inside the fuse box- near the intake area that I had somehow loosened while I was removing the intake. The connector was slightly cocked, and when I reseated it fully I was able to clear the codes and start the car. Not a problem since.

</DIGRESS>


Here's the list of codes related to the secondary MAP, FYI:

P1237 4663 Secondary Upstream Manifold Air Pressure Sensor Low Input
P1238 4664 Secondary Upstream Manifold Air Pressure Sensor High Input
P1239 4665 Secondary Upstream Manifold Air Pressure Sensor Too Low at Engine stop
P1240 4672 Secondary Upstream Manifold Air Pressure Sensor Too Low at Idle Engine Running
P1241 4673 Secondary Upstream Manifold Air Pressure Sensor Too Low at Full Load for Low Engine Speed
P1242 4674 Secondary Upstream Manifold Air Pressure Sensor Too High in Deceleration

 

I have the Ryephix spring in my car

 

The upstream MAP sensor outputs a voltage, no matter what the conditions. Since it is an ABSOLUTE sensor, even a strong vacuum reading still represents a pressure. What I am saying is that the ECU does not seem to like seeing an upstream MAP reading of much less that 150 mbar. I'm not sure where the cutoff is, but it seems to be between 159 and 109, given that the fault repeatably showed itself with the latter reading, but not with the former.

 

I have the Ryephix2 installed. Could that be a problem. Someone PMd me and said that after they removed the Ryephix 1 that their fault code 1237 went away.

What do you think Ryan?

 

SpiderX -

What ended up correcting your P1237 code? I just started getting the same code. On my car it seems to occur after a 5-10 second burst of full throttle acceleration followed by lift-throttle (strong vacuum).

(I do not have Ryephix #1 or #2 on my car, but I do have the VGS mod.)

Thanks in advance for the info.

 

WE ended up buying 2 new sensors and clearing the code and it was fine. I then developed a bad Cat and got a new one from Miltek and now it is in the shop for a crank sensor problem.....which the dealer has never seen before. The joys of modding your Mini

 

Thanks for sharing your experience.

I know there were some questions (because of your mods) about whether this would be covered under warranty. Was it covered?

 

OK, after some holiday vacationing and a weekend at Road Atlanta, I finally got a chance tonight to check into what was causing my car to throw this code. I had a conversation last week with Randy Webb about it. He suggested I check the connections to the sensor and also look closely at the wiring to the sensor for signs of wear or damage.

When that all checked out OK, I looked a little further and found the problem... The vacuum line had slipped off the bottom of the fuel pressure regulator.

Apparantly during the SC Pulley installation this line was tugged loose and subesquently slipped off entirely. This resulted in the P1237 code as well as sluggish acceleration, uneven throttle response and poor fuel mileage, so I'm happy to have found the problem. A quick test drive and a few starting cycles confirm that the problem has been corrected.

Hopefully I won't have any reoccurences, but I do worry a little, since the vacuum line I used for the VGS install doesn't fit especially snugly onto the FPR. Anyone have any suggestions for getting a more postive fit?

 

Good work

 

I just threw p1242 and p1238...now I tore down thru my bypass valve after a week of this code just coming back right after I would clear it. Bypass looks fine, seems to be working fine. right when I lift throttle my gauge goes way into vacuum..I have a warranty appt setup..but now the code wont even clear...and I tried leaving the battery off forever and putting it back on and the CEL was on right when it started back up

any ideas? I am running out of warranty ~500 miles and its up and my appt isn't until the 7th or something =/

 

where is the sensor located?

 

anyone?


hello...this thing on?

 

I suggest you find a friend with the Bently's manual or bite the bullet and order one.... I have forgotten what this was I have had so many codes

PM me and we can talk about it