P38 cold start issues

This site contains affiliate links for which LandyZone may be compensated if you make a purchase.
B

bionicbob

Member
Posts
35
Location
Doncaster
hi all im new to this recently got a p38 after running discos bad move lol
its a P38 2.5 DSE 1997
it takes about 4 turns of the key to start in a morning but once running starts every time
the temp gauge dosnt work as it moves to the bottom of blue when you turn it on and just stays there the cooling system is fine the heater blows hot as the engine warms up as it should also had my snapon scanner on it the ecu temp is not working and fuel temp they show a voltage of 4.9 on the scanner and also at the plugs for the sensors also check there is a earth showing from the plugs i have spent the last 3 days just reading posts on here and no one as posted any answers
would be greatfull if some one out there had maybe had this problem and fixed it
cheers Bob
 
Glow plugs would probably be the first port of call. I think @wammers says you need 4 good plugs on consecutively firing cylinders for a cold start (correct me if I'm wrong)
 
bionicbob said:
hi all im new to this recently got a p38 after running discos bad move lol
its a P38 2.5 DSE 1997
it takes about 4 turns of the key to start in a morning but once running starts every time
the temp gauge dosnt work as it moves to the bottom of blue when you turn it on and just stays there the cooling system is fine the heater blows hot as the engine warms up as it should also had my snapon scanner on it the ecu temp is not working and fuel temp they show a voltage of 4.9 on the scanner and also at the plugs for the sensors also check there is a earth showing from the plugs i have spent the last 3 days just reading posts on here and no one as posted any answers
would be greatfull if some one out there had maybe had this problem and fixed it
cheers Bob
Click to expand...
You need to sort the temperature sensor.
If they are in the right order, they will start on 3 plugs.
Your Snap on scanner may not work correctly on the P38 as it is not OBD compliant.
 
Datatek said:
You need to sort the temperature sensor.
If they are in the right order, they will start on 3 plugs.
Your Snap on scanner may not work correctly on the P38 as it is not OBD compliant.
Click to expand...
please correct me if im wrong but by bridging the terminals on the plugs then this should make my temp gauge show hot?
 
bionicbob said:
please correct me if im wrong but by bridging the terminals on the plugs then this should make my temp gauge show hot?
Click to expand...
No, the temperature gauge sensor is not the same one as the ECU sensor. The fact that the temperature is staying in the blue is often due to the thermostat being missing or faulty, so you have 2 separate problems with temperature plus maybe a glow plug issue. shorting things out is not a good idea on the P38 unless you really know what you are doing, you could easily end up damaging the BECM.
 
Datatek said:
No, the temperature gauge sensor is not the same one as the ECU sensor. The fact that the temperature is staying in the blue is often due to the thermostat being missing or faulty, so you have 2 separate problems with temperature plus maybe a glow plug issue. shorting things out is not a good idea on the P38 unless you really know what you are doing, you could easily end up damaging the BECM.
Click to expand...
no the temp gauge needle move up when you first turn the ignition on to just below the blue and thats where it stays all the time regardlees of engine temp the engine heats up fine then as it should
 
bionicbob said:
no the temp gauge needle move up when you first turn the ignition on to just below the blue and thats where it stays all the time regardlees of engine temp the engine heats up fine then as it should
Click to expand...
The temp gauge will move to the start of the blue regardless, you say the engine is getting hot but you do not know how hot and it needs to be quite hot before the gauge moves, they are not linear.
Maybe both temperature sensors are faulty but I think a check to see if a thermostat is fitted would be a good idea.
With suitable diagnostics the ECU engine temperature sensor and gauge temperature sensor can be read.
 
Datatek said:
The temp gauge will move to the start of the blue regardless, you say the engine is getting hot but you do not know how hot and it needs to be quite hot before the gauge moves, they are not linear.
Maybe both temperature sensors are faulty but I think a check to see if a thermostat is fitted would be a good idea.
With suitable diagnostics the ECU engine temperature sensor and gauge temperature sensor can be read.
Click to expand...
which is the best diagnostics to get as i do have the old britpart lynx
 
Have a look at the bleed off pipes they may be letting air in which will let the diesel bleed back which will not help starting, are there any air bubbles in the clear pipe from filter to pump,
 
You must log in or register to reply here.

Similar threads

JT_spark
P38 DSE Auto intermittent lack of power after vehicle has been hot
Replies
8
Views
470
brianp38dse
brianp38dse
K
P38 2.5TDI won't start
Replies
8
Views
673
Kelvin'D-MiC'
K
stuu
P38A Brands advice/suggestions
Replies
4
Views
606
stuu
stuu
F
P38 DSE loss of power when driving
2
Replies
33
Views
1K
Mark Piercy
Mark Piercy
P38Seb
P38A Viscous fan woes
Replies
8
Views
765
kermit_rr
kermit_rr
Back
Top