P38A Diagnostic lamp on - won't clear

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

pes

New Member
Posts
9
Location
Leeds, UK
Afternoon all. First question on here so apologies if it's in the wrong section. This is on a 96 2.5 DSE auto.

I've just recently got the diagnostic lamp come on (for the start of injection sensor on injector 4) and connecting a Hawkeye to read codes gave me fault code 142 - Needle lift sensor.

I'm a total novice so the only things I could think of doing were to check there was voltage to the socket where the sensor connects to see if power was getting to it (it was) and if there was resistance across the sensor itself (there was), just to check nothing was obviously broken.

With these checked I decided to clear the codes to see what happened but it wouldn't even clear them so my (ignorant) guess is that it's performing some self-check and failing on it. Does this sound reasonable and if so does anyone know what it's self check runs through?

EDIT: Bit more info. I activated the 'Timing Solenoid' through the EMS on Hawkeye thinking it was something to do with that sensor. It activated fine and the engine note cycled while it was running. I also monitored the live values for 'Injected quantity' and 'Start of Injection'. These showed as 16.3mg/s and "-3.0 degrees crank" both of which remained steady. I was thinking that if it's reading the start of injection as -3.0 degrees that the sensor itself was working. Anyone able to confirm that or am I talking ****e?

Cheers guys (and gals)
 
Last edited:
Sounds like #4 injector is duff.

There should be 2 rpm measures, one from the crank sensor and one from #4 and the comparison gives modulation. If one fails it will run on default values.
 
  • Like
Reactions: pes
Grrrrrr said:
Sounds like #4 injector is duff.

There should be 2 rpm measures, one from the crank sensor and one from #4 and the comparison gives modulation. If one fails it will run on default values.
Click to expand...

That's interesting.

The Hawkeye does have two RPM readings. I wondered why (the instructions for it are completely useless). It's got crank signal and engine speed. I guess the crank signal is from the CKP and the engine speed is from the SOI. The crank signal changes as expected when the accelerator is pushed and the engine speed stays at a solid 773, which is probably some default. So that's it then. Either that injector is stuck or no signal is coming from it.

Thanks for that. That's confirmed the problem then and saved me more time head scratching.

I don't suppose you have a clever method of probing the signal from it? It's impossible for me to reach the plug when the manifold is on. I've heard no-one makes these injectors anymore though, so where do people go to get replacements these days?
 
pes said:
That's interesting.

The Hawkeye does have two RPM readings. I wondered why (the instructions for it are completely useless). It's got crank signal and engine speed. I guess the crank signal is from the CKP and the engine speed is from the SOI. The crank signal changes as expected when the accelerator is pushed and the engine speed stays at a solid 773, which is probably some default. So that's it then. Either that injector is stuck or no signal is coming from it.

Thanks for that. That's confirmed the problem then and saved me more time head scratching.

I don't suppose you have a clever method of probing the signal from it? It's impossible for me to reach the plug when the manifold is on. I've heard no-one makes these injectors anymore though, so where do people go to get replacements these days?
Click to expand...
They are available but not cheap,
 
pes said:
That's interesting.

The Hawkeye does have two RPM readings. I wondered why (the instructions for it are completely useless). It's got crank signal and engine speed. I guess the crank signal is from the CKP and the engine speed is from the SOI. The crank signal changes as expected when the accelerator is pushed and the engine speed stays at a solid 773, which is probably some default. So that's it then. Either that injector is stuck or no signal is coming from it.

Thanks for that. That's confirmed the problem then and saved me more time head scratching.

I don't suppose you have a clever method of probing the signal from it? It's impossible for me to reach the plug when the manifold is on. I've heard no-one makes these injectors anymore though, so where do people go to get replacements these days?
Click to expand...

@Datatek might. It gives a pulse each time the needle in the injector lifts so 750 pulses a minute at idle. I guess an oscilloscope might pick up 12 pulses a second but I doubt a DVM would, although maybe you could check continuity somewhere?
 
  • Like
Reactions: pes
Grrrrrr said:
@Datatek might. It gives a pulse each time the needle in the injector lifts so 750 pulses a minute at idle. I guess an oscilloscope might pick up 12 pulses a second but I doubt a DVM would, although maybe you could check continuity somewhere?
Click to expand...
The needle lift sensors are available. You obviously have no signal from the sensor. First thing to check is the connector under the manifold.
No need for a scope, the diagnostics are sufficient, Crank sensor and NLS should show the same RPM but with some fluctuations.
 
  • Like
Reactions: pes
Thanks guys. The connector itself seemed fine when I had the manifold off previously. No corrosion and had power to it. Gave it a little squirt of contact cleaner as well, just in case. I was trying to read the wiring diagrams in RAVE to find out somewhere I could probe it with the engine running but then got knocked out with some serious flu so haven't had a chance to check this yet. It looks like it terminates in the wiring block just behind the battery so I'll try there.

I haven't attempted to read a wiring diagram in perhaps 30 years and I'm not sure if the vaguely remembered slivers of information that 16 year old me took in is going to be enough. It looks as though the ground is actually some shield, so the two wires coming from it both carry voltages of some description? Yep this is more complicated than a DC circuit consisting of a cell with light bulbs in series or parallel and a variable resistor, which is the limit of my memory of wiring diagrams. More reading required I think unless someone is able to explain this to me in a way that a 5 year old could understand it.
 
Have been unable to source a reliable no 4 injector and unfortunately don't have enough posts to post in the wanted section. Does anyone know someone selling one of these injectors?

Also meant to say, there is an open circuit between the two legs of the connector attached to my injector so I think that means the coil inside is gone. I guess.
 
For injectors - in fact all things P38, petrol and Diesels - give William Chetwynd a call.
If in stock, they'll be reasonably priced, tested and usually next-day delivery if you get him early enough.
Tel: 07903-167575
He's based in Lincoln.
 
Jon Dor said:
For injectors - in fact all things P38, petrol and Diesels - give William Chetwynd a call.
If in stock, they'll be reasonably priced, tested and usually next-day delivery if you get him early enough.
Tel: 07903-167575
He's based in Lincoln.
Click to expand...
Brilliant thanks. I'll give him a call tomorrow. Appreciate the info
 
pes said:
Have been unable to source a reliable no 4 injector and unfortunately don't have enough posts to post in the wanted section. Does anyone know someone selling one of these injectors?

Also meant to say, there is an open circuit between the two legs of the connector attached to my injector so I think that means the coil inside is gone. I guess.
Click to expand...

I rang the main Eurocarparts number and they got me one a few years ago.
 
Jon Dor said:
For injectors - in fact all things P38, petrol and Diesels - give William Chetwynd a call.
If in stock, they'll be reasonably priced, tested and usually next-day delivery if you get him early enough.
Tel: 07903-167575
He's based in Lincoln.
Click to expand...
Just messaged him now and he's going to have a look. Thanks for that.

Grrrrrr said:
I rang the main Eurocarparts number and they got me one a few years ago.
Click to expand...
Had a look on eurocarparts. Injector was a decent price but they wanted another £70-odd on top for 'service charge' that they refund if I send them my old one to recondition. I was under the impression these couldn't be reconditioned. I'll fire an email off to them and see what they say.

Datatek said:
Island 4x4 had them not so long ago. I think second had would be a waste of money.
Click to expand...
You might be right. Depending on what William says I may just go to island and order one. £300 though. Beginning to wonder if I should just buy up all remaining stock of these and sit on them or pass them down as family heirlooms. Seems like a good investment :)
 
My replacement was a 300€ bosch unit from over here in fwance.... o_O
Mine was actually leaking from around the seal for the wire/sensor. :(
 
Datatek said:
Same as mine on both counts:(
Click to expand...

This is by far the most common problem I've seen with these, which is why I thought I'd been quite lucky and it was just going to be a loose connection as the injector itself seemed fine. I don't think I found a single other post anywhere that has the same problem as me, namely completely open circuit through the coil. It also just happened immediately - no warning whatsoever.

Mark Piercy said:
My replacement was a 300€ bosch unit from over here in fwance.... o_O
Mine was actually leaking from around the seal for the wire/sensor. :(
Click to expand...

Glad to hear the price I've paid is about right, but my goodness that is expensive for a bit of metal and a spring. Don't know France at all well, but from the bits I've seen I imagine you've got some beautiful countryside to potter about in the Range over there. Jealous.
 
pes said:
This is by far the most common problem I've seen with these, which is why I thought I'd been quite lucky and it was just going to be a loose connection as the injector itself seemed fine. I don't think I found a single other post anywhere that has the same problem as me, namely completely open circuit through the coil. It also just happened immediately - no warning whatsoever.



Glad to hear the price I've paid is about right, but my goodness that is expensive for a bit of metal and a spring. Don't know France at all well, but from the bits I've seen I imagine you've got some beautiful countryside to potter about in the Range over there. Jealous.
Click to expand...
Yep, lots of empty roads as long as you stay away from Paris and other major cities. a traffic jam where I live is 6 cars in the queue at the traffic lights:D
 
Datatek said:
Yep, lots of empty roads as long as you stay away from Paris and other major cities. a traffic jam where I live is 6 cars in the queue at the traffic lights:D
Click to expand...
I saw five cars at the junction by the mayor's office once!! That's a first in 16yrs..
@pes Don't forget these injectors are around 20 odd yr oldo_O
 
Datatek said:
Yep, lots of empty roads as long as you stay away from Paris and other major cities. a traffic jam where I live is 6 cars in the queue at the traffic lights:D
Click to expand...

Whats a traffic jam? please jog my memory lol...they've replaced traffic lights nearly everywhere with roundabouts here which is ok for driving but a b.ugger cause the GNR use them for road checks...
 
You must log in or register to reply here.

Similar threads

I
Air.Susp.Inactive message on 2005 L322
Replies
4
Views
534
invisible999
I
M
Front wheel speed sensor fault?
Replies
2
Views
767
Mid-life-crisis
M
Blob
L322 Adaptive Dynamics Height Sensor issue (but it works...)
Replies
2
Views
711
Graculus
Graculus
G
RR 55 plate l322 vogue
2
Replies
30
Views
1K
stuu
stuu
F
P38 DSE loss of power when driving
2
Replies
33
Views
1K
Mark Piercy
Mark Piercy
Back
Top