Common Issue Limp Mode

[faisalak7]

Hi

i know this problem is mentioned here so many times but after spending too many days on searching could not find the solution , my problem is limp mode.

My 1.9 tdi auto 2004 (136K) galaxy is going into home limp mode if accelerated hard .

 

the error codes are

 

-Charge pressure control

Positive deviation -intermittent

 

-Manifold pressure sensor (G71)

Short to plus -intermittent

 

i dont know what to do , where to start from :(

 

Any help will be great

 

Thanks

[bigdave982]

Do a search fella,limp mode is covered endlessly

[seatkid]

 

 

-Charge pressure control

Positive deviation -intermittent

 

-Manifold pressure sensor (G71)

Short to plus -intermittent

 

 

Suggests a wiring problem to the Manifold pressure sensor (TMAP), possibly a poor connection. I think the TMAP on your car is located on the big black plastic circular (about 1.5 in dia) boost pipe that passes near the fuel filter. Check the connector and wiring first

 

IIRC a couple of people have said they removed the TMAP sensor from the boost pipe and found it all gunged up, and gave it a careful clean out with solvent and that cure their problems (but I dont know is the errror codes were the same).

[faisalak7]

-Charge pressure control

Positive deviation -intermittent

 

-Manifold pressure sensor (G71)

Short to plus -intermittent

 

 

Suggests a wiring problem to the Manifold pressure sensor (TMAP), possibly a poor connection. I think the TMAP on your car is located on the big black plastic circular (about 1.5 in dia) boost pipe that passes near the fuel filter. Check the connector and wiring first

 

IIRC a couple of people have said they removed the TMAP sensor from the boost pipe and found it all gunged up, and gave it a careful clean out with solvent and that cure their problems (but I dont know is the errror codes were the same).

 

Thanks guys

is there any way i can get my cars technical informaiton like where these parts are located and how to get to them .

[Saif Rehman]

Get a Haynes manual, recently released for your particular model. eBay has them - iirc aound £14-£16 delivered.

[faisalak7]

Thanks saif will this manual will have how to fit the curtain airbag .

 

Thanks

[seatkid]

As I told you, look to the right (passenger side) of the engine cover and you will see a big black rigid plastic pipe about 1.5 inch dia going from back towards the front. This is the boost pipe from the turbo going to the intercooler. About halfway, inserted in this pipe is located the TMAP sensor, it has an electrical connector on it. The connector probably has a latching mechanism on it so dont just pull it otherwise you may break something. You need to release the latch , this is usually done squeezing the tang and pulling the connector at the same time.

[faisalak7]

-Charge pressure control

Positive deviation -intermittent

 

-Manifold pressure sensor (G71)

Short to plus -intermittent

 

 

Suggests a wiring problem to the Manifold pressure sensor (TMAP), possibly a poor connection. I think the TMAP on your car is located on the big black plastic circular (about 1.5 in dia) boost pipe that passes near the fuel filter. Check the connector and wiring first

 

IIRC a couple of people have said they removed the TMAP sensor from the boost pipe and found it all gunged up, and gave it a careful clean out with solvent and that cure their problems (but I dont know is the errror codes were the same).

 

The Tmap sensor is been cleaned couple of times but no difference .

[faisalak7]

Bought tmap sensor i thing its compatible one but no difference so £45 wasted

[faisalak7]

Now some time car is not going into reverse gear while cold but when it reaches certain temperature it starts working .

showed to a local garage they disconneted the gearbox ECU gear starts working when they connect ECU same problem no reverse gear .

 

They are suggesting that it could be gear box ECU that is why car is going into limp mode

[faisalak7]

As I told you, look to the right (passenger side) of the engine cover and you will see a big black rigid plastic pipe about 1.5 inch dia going from back towards the front. This is the boost pipe from the turbo going to the intercooler. About halfway, inserted in this pipe is located the TMAP sensor, it has an electrical connector on it. The connector probably has a latching mechanism on it so dont just pull it otherwise you may break something. You need to release the latch , this is usually done squeezing the tang and pulling the connector at the same time.

 

Thanks for the picture now i know where it is .I paid some one £40 for diagnostics and guy said change the sensor and it will be fine so bought this sensor but no difference , car starts behaving strange so changed it and put back the original one.

 

How do you get these pictures from

 

Thanks

[alan_131]

I've read that problems with autobox ecu and/or its connectors can cause limp mode, and it certainly sounds like you might have a problem with this and reverse. However, my thought would be that you may have more than one problem, since the codes you originally posted usually relate to limp mode caused by the engine ecu thinking there's a problem with the sensor or the pressure in the inlet. (which there may be, or it could be the sensor or somewhere in the wiring to it. That's why seatkid said to work on the wiring and sensor first.

 

 

It may be that there's a common connection or something the loom that confuses things, but my suggestion fwiw would be to rescan/clear/rescan.... Do you own/can borrow a laptop? a vcds cable (ebay, <£10) and the free vcds software rom ross-tech will let you do your own scans and get lots of other info, like what pressure reading is coming from the sender - really helpful in your case. This topic has recent ebay suggestions for the cable http://www.fordgalax...akage-of-water/

 

Charge pressure control

Positive deviation -intermittent

 

This means that the ecu thinks the pressure in the inlet mainfold is higher than it should be. Most common cause I think of this (if it really is so) is the turbo producing more boost than it's supposed to at that time. Assuming you have one of the more powerful engines (not the 90) this can be stuck vanes on the turbo, dodgy turbo actuator, or contol valve stuck open.

 

However, the device that signals the pressure back to the ecu is the subject of your second fault

Manifold pressure sensor (G71)

Short to plus -intermittent

 

so I'd say, can't be trusted. Personally I'd not start on the turbo until this one was fixed. And you may have done that already with seatkid's advice. Back to where we came in - why I'm suggesting you clear the codes and do some checks with vcds....

Good luck!