Did I read earlier on that the spark plugs were getting wet with fuel? if thats the case wont the engine ecu need a signal from either the cam or crank position sender to know when to switch the injectors? If its just not sparking would it not be worth trying some known working coils on it?
 
Did I read earlier on that the spark plugs were getting wet with fuel? if thats the case wont the engine ecu need a signal from either the cam or crank position sender to know when to switch the injectors? If its just not sparking would it not be worth trying some known working coils on it?
Very True....and I have wonder this too....

Not sure on the P38, but I am sure the earlier Classics EFi system used to just squirt fuel into the cylinders during cranking and a double pulse on all 8 injectors during accelrating regardless of firing order...as it fired opposing injectors in a single set of 4 as it wasn't truly sequential and very basic...if the P38 system operates similar during cranking it may just be non-sequential until it fires and the CPS signal speed rises...

Will read RAVE Further!
 
hmmmm RAVE doesn't give the injector pulse information of when it fires, so I can only assume it is sequential at all times...

Also Coil Pack Failure would activate MIL (CEL) as D300 says...so while yes known good coils would be a test - if the originals were faulty, I am fairly sure a CEL would occur....my only guess is the ECU doesn't know the Engine is turning over - but as you say if this is the case why are the plugs wet?
 
Very True....and I have wonder this too....

Not sure on the P38, but I am sure the earlier Classics EFi system used to just squirt fuel into the cylinders during cranking and a double pulse on all 8 injectors during accelrating regardless of firing order...as it fired opposing injectors in a single set of 4 as it wasn't truly sequential and very basic...if the P38 system operates similar during cranking it may just be non-sequential until it fires and the CPS signal speed rises...

Will read RAVE Further!
yes they werent sequential and just fired fuel in valve port a bank at a time ,i thought p38s were the same
 
Looking at the Temp readings in the posted screenshots and with it being so wildly different from 3 other readings from 3 other P38's (incl a Diesel) could be an issue....

But according to the attached, if the ECT and the other Coolant sensors were diffrent it would throw a Code....as attached.....

I may be a nother test to bridge the ECU Temp sensor with a resistor of a value from the attached table to fool the ECU into thinking it is a different temp and see what happens!
 

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can anyone recomend someone to come and check this out guys im lost off big time got no kit to check it with, dont know what im doing ethier

im going to fit the crank sensor and mabe try some coils if this doesnt work NWRRS can take it away for scrap ive had enough im beat....ive got no more money to throw at it its cost £600 so far... think im just going to cut my loses and bail....
 
can anyone recomend someone to come and check this out guys im lost off big time got no kit to check it with, dont know what im doing ethier

im going to fit the crank sensor and mabe try some coils if this doesnt work NWRRS can take it away for scrap ive had enough im beat....ive got no more money to throw at it its cost £600 so far... think im just going to cut my loses and bail....
Whilst I feel your pain....if it indeed comes to scrap it - take the BeCM, ECU's and other such components out (EAS Comp, Valve Block etc) and flog on the bay to recoup you £600....

Compressor £80?
ECU's £50? a throw (ABS, Transfer Case, Gearbox, Engine)
BeCM £150?
Valve Block £120?
HEVAC Head Unit £75?
Subwoofer and Amp £75?

Plus Scrap weigh in at £135 per tonne = £250

So thats £950 (if yer lucky on the bay that is - or if only flogging the Engine ECU as known good and ditch the ABS, TB and GB - £800)

But I would hate to see it come to that - but I also understand where you are coming from having had 2 P38's I had to get rid of due to costs....
 
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Saint i dont want to scrap it ive £3500 in it now and its going to be nearly all blown ive just got no idea at all with electrics its proabably a £3 fuseable link blown somewhere but ive no idea where or how to trace it..

i might just take some bits off and chop the rest up in the garage and take it away bit by bit then i wont be ****ed off if someone takes it away and fixes for £50....

see what happens they cant be many rot free 49k miles P38 for breaking about i suppose..
 
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Saint i dont want to scrap it ive £3500 in it now and its going to be nearly all blown ive just got no idea at all with electrics its proabably a £3 fuseable link blown somewhere but ive no idea where or how to trace it..

i might just take some bits off and chop the rest up in the garage and take it away bit by bit then i wont be ****ed off if someone takes it away and fixes for £50....

see what happens they cant be many rot free 49k miles P38 for breaking about i suppose..

It needs a scope on the relevant lines, shame you are so far away:(
 
Silly question, but has the ignition relay been checked/changed? A dodgy relay may show 12 volts passing when there is no load but drop too much voltage when on load.
 
He did try Sassanach's Fusebox which I believe included all th relays and fuses...!
 
Silly question, but has the ignition relay been checked/changed? A dodgy relay may show 12 volts passing when there is no load but drop too much voltage when on load.


Hi Keith,

Must confess, I was wondering about relays...

What else could possibly have got damaged by the short though? There can't be that many candidates. I bet it's something really simple.

Have I understood how it works correctly in that the coil packs receive a modulated signal causing them to spark appropriately? A short somewhere holding the pack inputs at 12V would explain the symptoms wouldn't it? If so, could we try bridging the connection to the coil packs from wherever the modulated signal comes from? Are both packs fed from a common source? Seems odd that they're both not working.

Or is that all just gibberish?
 
Hi Keith,

Must confess, I was wondering about relays...

What else could possibly have got damaged by the short though? There can't be that many candidates. I bet it's something really simple.

Have I understood how it works correctly in that the coil packs receive a modulated signal causing them to spark appropriately? A short somewhere holding the pack inputs at 12V would explain the symptoms wouldn't it? If so, could we try bridging the connection to the coil packs from wherever the modulated signal comes from? Are both packs fed from a common source? Seems odd that they're both not working.

Or is that all just gibberish?

Hi Guy, I assumed that maybe the replacement fuse box was just that, a fuse box with relays removed to save postage.
I think the coil packs are fed with 12 volts one side and the pulse to fire them is on the other side.
I can't really id the wire he say's he shorted but everything on that line needs to be checked and yes I would bet it turns out to be something simple.
 
Did the alarm get reconnected properly?

Is it possible that something is amiss with the wiring for that? That might stop it sparking. Not sure my alarm works so I've no knowledge of how it is supposed to operate.

The gearbox fault worries me slightly though. It doesn't seem relevant, but I think it started doing it as a result of the short so it could at least be related.

Gearbox fault messages are often caused by low battery voltage. Is there a common earth that the gearbox uses that could be related to the alarm/ignition? Or a connection? Could the gearbox ECU be fried and that's stopping the engine ECU from allowing the ignition to fire?

I can't recall the details now, but I was quite surprised at just how interlinked the engine and gearbox ECUs are when I was investigating my random kick down problem. That turned out to be a bad connection too.

Just wondering out loud...
 
Hey guys I'm blown on this now but I've found something else I've gone back to basics and checked all the fuses and on the Ebcm fuse 11 was missing on rave its said 30a fuse not sure if its all models but it has metal contacts in the female side fitted a fuse still nowt.... So tested all the fuses still ok all of them so I thought ok check for fuel pressure,,,

I've found they do have a schraider valve on the left rail or right rail viewed from the front it's tight to get on but I've unscrewed the cap pushed valve in got a tiny spirt of fuel with someone operating the key and the schraider valve pressed in no fuel not even with ignition lights on nothing ?

So I got the wife to crank engine while I held the valve depressed on fuel rail still no fuel when cranking ??

But I've still no spark ether xxx

I'm loosing the will to live now to be fair...
 
Hi Keith,

Must confess, I was wondering about relays...

What else could possibly have got damaged by the short though? There can't be that many candidates. I bet it's something really simple.

Have I understood how it works correctly in that the coil packs receive a modulated signal causing them to spark appropriately? A short somewhere holding the pack inputs at 12V would explain the symptoms wouldn't it? If so, could we try bridging the connection to the coil packs from wherever the modulated signal comes from? Are both packs fed from a common source? Seems odd that they're both not working.

Or is that all just gibberish?
both coils are Fired Simultaneously One is a ghost spark Depending on the revolution
 
The fuel system should be pressureised to 45psi or so, so there should be quite a spurt if there was pressure.

The Packs are fired using the Wasted Spark method - all the coils are not fired simultaniously, it is two cylinders fired at once one on the compression stroke and one on the exhaust....

1&6, 4&7, 5&8 + 2&3.....
 

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My alarm is unplugged still and all fires up but it is a diesel is there any way the alarm can be triggerd so that it can be reset ??? I thought super lock someone one inside get them to move after required time set alarm off and then reset ?? Is this possible
 
Just been re-reading the Ignition Coils in RAVE....coil failure won't cause MIL light - but a misfire caused by coil failure will......substituting with known good coild would be a good test...
 

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