Hi Wammers,

No MIL light. I have the mechanic that took the FIP off here now with his snap on box. Faults showing are -47 degrees on intake, engine coolant temp = 145degrees. I haven't changed the wires you told me about in December as I wanted to fix the FIP first.
 
If yours is the later engine I think 1 of the temperature sensors does have a silly value by default. It isn't wrong. 145 F?

I managed to recreate your symptoms by disconnecting the turbo outlet from the intercooler. Sure the turbo is working?
 
To be honest Grrrrrr no. It's been parked for a few months. When I rev it up in neutral I can feel the pipe pressurise but it didn't seem to increase pressure in the pipe that much.
 
So in summary the diagnostic box showed:
  • boost pressure sensor problem
  • inlet temp problem -47F
  • engine temp problem +145F
 
There should be quite a bit of pressure 1 bar- 15psi if remember correct, it should be enough to pop the hose of the inlet manifold with clip removed.
Dopey on here had a problem of lack of power and it turned out to be the boost pressure sensor, cheep and easy to replace worth a shot
there are not many code readers that will work with a p38 the temp codes may be wrong .
 
Just checked my file. The EGR one has a silly minus air temperature. So the coolant is a bit of a mystery.

Good call from Brian on the clips. Loosen up and see if the pipe pops off!
 
Hi Wammers,

No MIL light. I have the mechanic that took the FIP off here now with his snap on box. Faults showing are -47 degrees on intake, engine coolant temp = 145degrees. I haven't changed the wires you told me about in December as I wanted to fix the FIP first.

Ok give me a few reminders. What year is your car? Which wires did we talk about?
 
Did you not read my last post? You do not need to change the ECU. Just leave everything as it is. Basically you are running the car with the EGR disconnected that is all, as long as you leave the MAF and EGR modulator connected all will be fine. You need to look at the temp gauge sensor and maybe fit the overheat sensor (Black unit) to the back port on the new engine which if yours is MY 1999 it should have fitted. If you now have an alloy manifold you will need a new top turbo hose no need to connect the IAT sensor under the manifold.. BECM will need syncing to any new ECU that is set robust before car will run. You need a MSB106370 ECU.
99 P38 now with non EGR 2.5tdi
 
Just checked my file. The EGR one has a silly minus air temperature. So the coolant is a bit of a mystery.

Good call from Brian on the clips. Loosen up and see if the pipe pops off!

Turbo is working fine - lots of pressure coming out. Just has asthma when the boost fuelling kicks in
 
Did you not read my last post? You do not need to change the ECU. Just leave everything as it is. Basically you are running the car with the EGR disconnected that is all, as long as you leave the MAF and EGR modulator connected all will be fine. You need to look at the temp gauge sensor and maybe fit the overheat sensor (Black unit) to the back port on the new engine which if yours is MY 1999 it should have fitted. If you now have an alloy manifold you will need a new top turbo hose no need to connect the IAT sensor under the manifold.. BECM will need syncing to any new ECU that is set robust before car will run. You need a MSB106370 ECU.
99 P38 now with non EGR 2.5tdi

Right thanks. You should have three temp sensors on a MY 1999 car. First one just above injection pump between cylinders 1 and 2 should be a blue two pin sensor (Gauge temp sensor). Second one between cylinders 3 and 4 should be green two pin sensor (ECU temp sensor). Third one between cylinders 5 and 6 should be black (Overheat sensor). You must fit these to your new engine. You will not have a loom for the manifold temp sensor. Leave it redundant. Inlet air temp on diag should read -38.88 degrees that is the preset to ensure EGR operates. Leave MAF sensor and EGR modulator connected. Disconnecting them may upset the engine ECU. You should have a MSB106370 engine ECU if your car is automatic. I don't regard Snap-on diag as good enough for these cars. I have heard some really airy fairy readings quoted off them. You MUST have the temp sensors fitted as listed. Although a one pin brown pre 1997 gauge sensor should work if you can't get a blue two pin one. As long as the green wire on pin one of plug goes to the single pin on the sensor. ECU sensor MUST be two pin green sensor, both wires from this go into the engine ECU. No other sensor will do for this, it works differently than the others. Check what you have and let me know.
 
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Morning Wammers,
I had a look this morning before i left for work and I can only see black plugs going into 1/2 and 3/4. I can't see any colours, I'm guessing I'll have to take the manifold off to see properly. The back port has a great big blanking bolt in it.
Is Saturday afternoon good to come up? My wife has a bike MOT at 1230
cheers,
Hoppy
 
Morning Wammers,
I had a look this morning before i left for work and I can only see black plugs going into 1/2 and 3/4. I can't see any colours, I'm guessing I'll have to take the manifold off to see properly. The back port has a great big blanking bolt in it.
Is Saturday afternoon good to come up? My wife has a bike MOT at 1230
cheers,
Hoppy

All the plugs are black it's the colour of the sensor that is important. If your car is MY 1999 it should have a loom plug for the black sensor for overheat if it has aircon. If it is MY 1998 first registered 1999 it will not have.
 
Morning Wammers,
I had a look this morning before i left for work and I can only see black plugs going into 1/2 and 3/4. I can't see any colours, I'm guessing I'll have to take the manifold off to see properly. The back port has a great big blanking bolt in it.
Is Saturday afternoon good to come up? My wife has a bike MOT at 1230
cheers,
Hoppy

Sat is fine. PM me Friday night and i will give you directions.
 
Wammers are these part numbers for these sensors please? I've been sat on google all morning at work
green - STC2299
black one - STC2254 - not on my car, blanked off
blue - NSC100820
I'll check the colours once I'm home tonight. I appreciate all your help guys & girls, thanks :D
Yes those are correct. Black overheat sensor is only fitted to MY (Manufacturing year) 1999 and on with air conditioning. Turns on aircon fans to assist cooling above certain temperatures.
 
I definitely have the blue sensor between 1&2, can't get my hands - or my wifes - in to release the middle one as we don't have the hands of an elf! Manifold will have to come off to check which I'll have to do tomorrow now.
 
I definitely have the blue sensor between 1&2, can't get my hands - or my wifes - in to release the middle one as we don't have the hands of an elf! Manifold will have to come off to check which I'll have to do tomorrow now.

Mirror? USB endoscope?
 
Yes those are correct. Black overheat sensor is only fitted to MY (Manufacturing year) 1999 and on with air conditioning. Turns on aircon fans to assist cooling above certain temperatures.
I have MY99 with EGR and MAF sensor, newer 4 wheel ETC, but orange indicators and it does not have one. Some kind of cross model. So MY99 does not always mean all things are newer desing.
 
I have MY99 with EGR and MAF sensor, newer 4 wheel ETC, but orange indicators and it does not have one. Some kind of cross model. So MY99 does not always mean all things are newer desing.

Depends when your car was built mine was built 1998 with EGR and MAF registered 1999 and does not have overheat sensor. MY year 1999 should all have them. There is a cut off point every year when old specs stops and vehicles start to be built to next spec. There were a lot of wiring changes and fuse box changes for MY 1998 to MY 1999. If your car does not have the fuse position changes and relay 3 and newer fuse box layout it is not a MY 1999.
 

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