P38 starting problems

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I will give it a clean out if I can. Glows now changed. Leak off pipes look good apart from the one on the first injector that goes back down to the injector pump. That's really badly split. Possible cause to issues?
 
This is done, to prevent the EGR from opening up and allowing crap air into the engine.

It is reportedly better for Fuel Consumption and gives a tickle more low down grunt....

Loads of posts on the matter, do a site search for EGR Blanking
 
Next problem...... To go with all the rest. Don't seem to be going in 1st gear

Edited: ignore that. It does. It's just really really slow to take off as though its in 2nd
 
Last edited:
Saint.V8 said:
This is done, to prevent the EGR from opening up and allowing crap air into the engine.

It is reportedly better for Fuel Consumption and gives a tickle more low down grunt....

Loads of posts on the matter, do a site search for EGR Blanking
Click to expand...
I can now say with confidence that it make no measurable difference to fuel consumption but it does stop all the crap collecting in the manifold:)
 
shaunm41 said:
I will give it a clean out if I can. Glows now changed. Leak off pipes look good apart from the one on the first injector that goes back down to the injector pump. That's really badly split. Possible cause to issues?
Click to expand...
If it's letting air back into the FIP that could be the cause of your problem.
 
shaunm41 said:
Next problem...... To go with all the rest. Don't seem to be going in 1st gear

Edited: ignore that. It does. It's just really really slow to take off as though its in 2nd
Click to expand...
Hmmmmm could be the MAP sensor tube is blocked or split or not attached....

The MAP sensor is ontop of the fuel filter and should have a thin pipe connected to it and the underside of the intake manifold!
 
That was split so I replaced it when I was doing the plugs. It's at the point where it's actually dangerous to pull out of a junction as its that slow untill it hits 2000 rpm then it's off like a good un
 
shaunm41 said:
That was split so I replaced it when I was doing the plugs. It's at the point where it's actually dangerous to pull out of a junction as its that slow untill it hits 2000 rpm then it's off like a good un
Click to expand...
I think Live Data readings will help now to see if the MAP sensor and Fuel Pump timing are within limits...

Sluggish before 2000rpm is most attributable to MAP sensor issues...or fuel pump timing/modulation!
 
Where could I get that done? I'm gonna struggle now till after Easter. But the starting issue is the main issue for now. It's got a full tank of fuel too so dose that rule out lift pump issue?
 
This might help:-
INTRODUCTION.
The maf or air mass meter or airflow meter is the biggest cause of poor performance and economy on modern diesel engines
Unfortunately, they are not a reliable component and this means that as many as 50% of diesel vehicles on our roads could have an out of spec maf sensor to the detriment of economy, performance and emissions, which is ironic because its an important component in emissions control!!.
These are the main symptoms of an out of spec or faulty maf:
1) poor performance especially below 2000rpm
2) an unexplained rise in fuel consumption.
3) flat spots, hesitation, juddering, exhaust smoke, stalling.
4) very poor throttle response - engine takes ages to accelerate to 2000rpm even in neutral due to a very weak or non existent maf signal
5) engine won't start - with no maf signal no fuel will be injected so the engine does not start.
6) engine won't rev out in the lower gears nor even in neutral
WHY DOES THE MAF HAVE SUCH AN IMPACT?
The engine management system uses the maf sensor to measure the mass of air entering the engine. At low rpm when the turbo is not working efficiently and there isn't an abundance of air available, it is important for performance, emissions and fuel consumption that the air is accurately measured. If the maf signal is below par the fuelling is reduced and performance suffers, if it is too high, fuelling is increased leading to smoke, and poor mpg, as well as lumpy, hesitant, juddery# running. In extreme cases stalling or bad starting can occur.

The egr valve...
The ecu also uses the maf signal to control the exhaust gas recirculation (egr) system. When exhaust gas is admitted it replaces inducted air so the maf signal drops. The ecu can therefore determine how far to open the egr valve. If the maf signal is unusually high, too much exhaust gas can be admitted or the egr valve does not close quickly enough or sufficiently when the throttle is opened. This causes hesitation and flat spots as well as performance issues.
 
shaunm41 said:
have just disconnected the pipe from map sensor and blocked it up there was no change to driving at all.. so this could be faulty?
Click to expand...

Clear any blockage in the map sensor (carefully) and it's electrical connector. Make sure outlet from manifold is clear make sure pressure pipe is clear and has no splits. There should be a marked difference in engine speed pick and power with MAP disconnected.
 
wammers said:
Clear any blockage in the map sensor (carefully) and it's electrical connector. Make sure outlet from manifold is clear make sure pressure pipe is clear and has no splits. There should be a marked difference in engine speed pick and power with MAP disconnected.
Click to expand...
More power with the MAP disconnected? Most seem to suffer with a loss of power when the MAP is disconnected or not working as the EDC runs on default to protect the engine:confused:
 
Very informative post thanks for that. I will check and change both the map and maf sensors and see what happens.

Anyone know where to find these tho? Really struggled to find map. Landrover took 45 mins to find it and they call it a turbo boost pressure sensor. £75+vat
 
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