- Posts
- 19,297
- Location
- Buckinghamshire, UK. ('95 DT)
And MAP too?
Diesel stalling in hot weather
- Thread starter Grrrrrr
- Start date
This site contains affiliate links for which LandyZone may be compensated if you make a purchase.
And MAP too?
- Posts
- 58,170
- Location
- Preston Lancs.
The MAP sensor has no input at tick over with throttle demand below 9% and idle switch engaged.
ovalandrover
Well-Known Member
- Posts
- 1,610
I have just had my pump tested and reconed by AP diesels and it seem to have made a lot of difference to hot start but to be fair I havn't given it a really good run yet.
It cost me 550pounds plus vat and I posted it to them Monday mourning and received it back Saturday at 8 am very impressed with their service.
It cost me 550pounds plus vat and I posted it to them Monday mourning and received it back Saturday at 8 am very impressed with their service.
- Posts
- 19,297
- Location
- Buckinghamshire, UK. ('95 DT)
Do you know what they did exactly?
I'd love to know what calculations the EDC module does. A flow chart would be a start. The Bosch manual is only high-level and is pretty much replicated in RAVE.
My next port of call is to read up how the hot-start fix works. I think Dopey knows something about this? Or knows someone who does.
As long as I the temperature does go much over 20 degrees I'm OK.
Datatek
Well-Known Member
- Posts
- 44,887
- Location
- Near Poitiers SW France
Hot start fix simply makes the EDC think the engine is cold by interfering with the engine temperature sensor reading using a substitute resistance. The good ones have a timer, the bad ones don't so the engine always runs with a rich mixture.Do you know what they did exactly?
I'd love to know what calculations the EDC module does. A flow chart would be a start. The Bosch manual is only high-level and is pretty much replicated in RAVE.
My next port of call is to read up how the hot-start fix works. I think Dopey knows something about this? Or knows someone who does.
As long as I the temperature does go much over 20 degrees I'm OK.
ovalandrover
Well-Known Member
- Posts
- 1,610
The hot start fix works by fooling the ecu into thinking the engine is cold and operates the cold start system which is increased fuel to the injectors and glow plugs operating
It does this by bypassing the ecu temperature sensor.
It does this by bypassing the ecu temperature sensor.
- Posts
- 19,297
- Location
- Buckinghamshire, UK. ('95 DT)
There's is something positive from the weekend's work. Always required 2 cycles of glow-plugs to start in the past, even with new Delphi plugs. Now, one cycle and bang!
- Posts
- 19,297
- Location
- Buckinghamshire, UK. ('95 DT)
Getting closer ...
Dummies guide to diesel injection here: http://killerbeeperformance.com/download/tuning/Timing the Diesel.pdf
This is for the Omega B but same engine as the Range Rover - different ECU maps but gives an overview of the MSA-11 ECU used in the engine management: Inside the 2.5TD ECU
And this is a bit more generic but same chips but more maps: http://gershon.ucoz.com/landrover/MSA-11.pdf
Unfortunately they're all about the driver wish as they're trying to increase performance when you mash your foot into the Axminster. What I really need is the other stuff!
Dummies guide to diesel injection here: http://killerbeeperformance.com/download/tuning/Timing the Diesel.pdf
This is for the Omega B but same engine as the Range Rover - different ECU maps but gives an overview of the MSA-11 ECU used in the engine management: Inside the 2.5TD ECU
And this is a bit more generic but same chips but more maps: http://gershon.ucoz.com/landrover/MSA-11.pdf
Unfortunately they're all about the driver wish as they're trying to increase performance when you mash your foot into the Axminster. What I really need is the other stuff!
ovalandrover
Well-Known Member
- Posts
- 1,610
Do you know what they did exactly?
I'd love to know what calculations the EDC module does. A flow chart would be a start. The Bosch manual is only high-level and is pretty much replicated in RAVE.
My next port of call is to read up how the hot-start fix works. I think Dopey knows something about this? Or knows someone who does.
As long as I the temperature does go much over 20 degrees I'm OK.
The parts replaced were as follows
WE REPLACED FOLLOWING
POSITIONER
CAM RING ROLLERS
DRIVE BUSHES
VACUME PUMP
- Posts
- 19,297
- Location
- Buckinghamshire, UK. ('95 DT)
That doesn't seem to include sensors / electronics, unless they're counting that under positioner.
Wonder if you can just get the elecwizardry in the top of the pump, assuming that's where the sensor is?
- Posts
- 58,170
- Location
- Preston Lancs.
Positioner is the mid section of the pump and all it's bits and bats. Don't know quite where they get the vacuum pump from there isn't one, there is however a high pressure pump that will draw fuel from the tank. Maybe just different terminology.
- Posts
- 19,297
- Location
- Buckinghamshire, UK. ('95 DT)
By positioner I assumed they meant that square thing with a notch that goes up and down the rail. You did tell me the name but already I've forgotten again!
- Posts
- 58,170
- Location
- Preston Lancs.
I take it they mean the quantity control servo.
- Posts
- 19,297
- Location
- Buckinghamshire, UK. ('95 DT)
That'll be the one. Car's run like a dream the last few days. Might have thrown its hissy fit for another year. Bit annoying not knowing if/when it'll do it again though.
- Posts
- 19,297
- Location
- Buckinghamshire, UK. ('95 DT)
Just reading through the electrical section part of RAVE, I tend to forget about this section. Interesting paragraph here:
Engine Coolant Temperature Sensor (X126)
This sensor is a ‘thermistor’ (a temperature dependent resistor) where the voltage output varies in proportion to coolant temperature. The ECM (Z132) uses this information in many strategies, i.e. to correct the injected fuel quantity and timing (especially during cold starts), length of glow plug timing, etc. The sensor is located in the top of the engine lock. In case of a failure, the warning lamp is not activated and the ECM (Z132) selects a substitute value of 50C for glow plug and ignition timing and uses the fuel temperature to correct the fuel quantity, glow plug timing will not be correct, possibly resulting in long rank times in cold weather as well as slight fuelling effects. These symptoms may not be noticeable.
That tells me the timing modulation is not based solely on crank position sensor and no 4 injector pulse. My guess is that this is one of those inputs that doesn't affect warning lamp but will affect timing and also amount of fuel injected and hence stalling when dipping the clutch. If only the Nanocom could record all inputs to the EDC at once. I think I'll try and find the right menu and take a trace ...
Engine Coolant Temperature Sensor (X126)
This sensor is a ‘thermistor’ (a temperature dependent resistor) where the voltage output varies in proportion to coolant temperature. The ECM (Z132) uses this information in many strategies, i.e. to correct the injected fuel quantity and timing (especially during cold starts), length of glow plug timing, etc. The sensor is located in the top of the engine lock. In case of a failure, the warning lamp is not activated and the ECM (Z132) selects a substitute value of 50C for glow plug and ignition timing and uses the fuel temperature to correct the fuel quantity, glow plug timing will not be correct, possibly resulting in long rank times in cold weather as well as slight fuelling effects. These symptoms may not be noticeable.
That tells me the timing modulation is not based solely on crank position sensor and no 4 injector pulse. My guess is that this is one of those inputs that doesn't affect warning lamp but will affect timing and also amount of fuel injected and hence stalling when dipping the clutch. If only the Nanocom could record all inputs to the EDC at once. I think I'll try and find the right menu and take a trace ...
- Posts
- 58,170
- Location
- Preston Lancs.
ECU temp sensor can cause problems but if it is duff should be recorded as such on Nanocom.
- Posts
- 19,297
- Location
- Buckinghamshire, UK. ('95 DT)
I'm thinking some sort of electronics starts giving odd values when the weather is very hot. Just need to catch it at it!
- Posts
- 58,170
- Location
- Preston Lancs.
Have you tried cleaning the plug connection to the timing solenoid, the one on the bracket near the lower side of the injection pump? If the modulation is drifting at idle and the number four injector is sending correct info about point of injection, it can only be the timing solenoid or the ECU causing it. The static timing cannot drift.
Datatek
Well-Known Member
- Posts
- 44,887
- Location
- Near Poitiers SW France
You really need to remove the hot start fix as that can affect the coolant temperature sensor readings to the EDC. You are chasing rainbows with it fitted.
- Posts
- 19,297
- Location
- Buckinghamshire, UK. ('95 DT)
Yeah, I know. I've never liked having it on but I tend to go with the adage 'if it ain't broke then don't touch it!'. Some time it'll have to go but I'd like to get the proper timing tools and make sure everything is right first. A car that runs 364 days a year is better than one that won't start when hot!
