P38A 2.5dse idle

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tarphenry

tarphenry

Well-Known Member
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bury lancs
Hi my tickover is slightly high (800ish) and the idle value on nanocom is 132. if i reduce the value by 2 the tickover roughens slightly.if I then return to 132 the tickover is smooth. I presume that this is a sign of wear.Is it fixable simply or am I in for a big job. thanks .
 
tarphenry said:
Hi my tickover is slightly high (800ish) and the idle value on nanocom is 132. if i reduce the value by 2 the tickover roughens slightly.if I then return to 132 the tickover is smooth. I presume that this is a sign of wear.Is it fixable simply or am I in for a big job. thanks .
Click to expand...
There are other things to look at. Timing modulation for one. Tick over should be 750 plus or minus 50 RPM so 800 is within that band. But setting should be 128. Has the pump top been played with?
 
hi, not by me,no. the engie was replaced by landrover with a new bmw replacement 50k miles ago. I have no problems with the engine, starts and runs really well uses no oil and has given me no problems. its just that I have the nanocom and have been looking at various results .maybe I am just paranoid.
 
tarphenry said:
hi, not by me,no. the engie was replaced by landrover with a new bmw replacement 50k miles ago. I have no problems with the engine, starts and runs really well uses no oil and has given me no problems. its just that I have the nanocom and have been looking at various results .maybe I am just paranoid.
Click to expand...

Tickover should be rock steady at 750 RPM when Nanocom is set at 128. Learn how to use the Nanocom, read through the instructions and don't change anything without noting what the setting was.
 
The fact the setting is 132 makes me think someone was tinkering at the start then. Have a look at the top of the FIP pump for marks where the joins are or for the security bolt being tampered with. If Land Rover did the engine I bet they swapped the old FIP over.
 
Hi all, give everything a good coat of looking at today to establish what needs doing. I would like some clarification on adjusting the static timing to bring modulation to 50%. 1 I know that the inlet manifold needs to be removed,Will engine tick over without it. 2 The adjustment, I am assuming is in very small amounts (say1/4mm) 3 Do I need to pin the flywheel to do the adjustment 4 The way I understand what i have read is that I warm engine, remove inlet manifold,loosen pump slightly tap pump small amount,tighten pump start then check with nanocom repeat until modulation reads 50%.Refit manifold then use nanocom to reset tickover to 750( about 128 on nanocom) Sorry if I appear thick but before I start spannering, I need to know what I am doing and the direction I am heading. thanks in advance
 
tarphenry said:
Hi all, give everything a good coat of looking at today to establish what needs doing. I would like some clarification on adjusting the static timing to bring modulation to 50%. 1 I know that the inlet manifold needs to be removed,Will engine tick over without it. 2 The adjustment, I am assuming is in very small amounts (say1/4mm) 3 Do I need to pin the flywheel to do the adjustment 4 The way I understand what i have read is that I warm engine, remove inlet manifold,loosen pump slightly tap pump small amount,tighten pump start then check with nanocom repeat until modulation reads 50%.Refit manifold then use nanocom to reset tickover to 750( about 128 on nanocom) Sorry if I appear thick but before I start spannering, I need to know what I am doing and the direction I am heading. thanks in advance
Click to expand...

To answer your question, yes, runs fine with the manifold off. Just make sure nothing goes down those inlet holes! And yes, tiny movements but mark up on all sides first. 2 marks if possible with as sharp an implement as you can and then with pen too so you can get it back EXACTLY where it was. Lost a lot of hours with mine when I had a play until I got it back to 750 rpm.

I really wouldn't touch the top of that pump unless you're sure someone has been playing with it. Frankly if it is ticking over at 800 rpm and there are no other issues whatsoever I'd be thinking that'll do. It might be hiding an underlying problem (like tired FIP or maybe tired lift-pump) but until it manifests itself I'd leave it!
 
Mind you, I say that but mine was OK on 750 rpm and I had to have a play ... so really I'm advising you not to do something that I blatantly went ahead and did anyway! So, let me know how you got on!
 
I think you may well be right,car starts and runs really well. I may well just be looking for work. the engine has no issues at all so perhaps I will leave it until a problem develops.
 
tarphenry said:
Hi all, give everything a good coat of looking at today to establish what needs doing. I would like some clarification on adjusting the static timing to bring modulation to 50%. 1 I know that the inlet manifold needs to be removed,Will engine tick over without it. 2 The adjustment, I am assuming is in very small amounts (say1/4mm) 3 Do I need to pin the flywheel to do the adjustment 4 The way I understand what i have read is that I warm engine, remove inlet manifold,loosen pump slightly tap pump small amount,tighten pump start then check with nanocom repeat until modulation reads 50%.Refit manifold then use nanocom to reset tickover to 750( about 128 on nanocom) Sorry if I appear thick but before I start spannering, I need to know what I am doing and the direction I am heading. thanks in advance
Click to expand...

Static pump timing should not effect the idle speed. Only moving the pump top back and forth will do that. Idle speed is about fueling not timing. Do not under any circumstances run the engine with a loose pump. Slacken pump, (Slightly) tap towards engine slightly using an hammer and block of wood to advance (lower modulation) and away to retard (raise modulation) tighten pump up, only THEN start engine and check modulation. Scribe a witness mark on pump flange and engine case as a reference. Only move pump a couple of mm at a time either way. It can take some time to get it correct. Engine will happily run with manifold off just make sure there is nothing that can get sucked in around. Modulation should be between 45% and 55% engine HOT at idle. Ideally 50% but that could take some doing unless you are lucky.
 
Thanks for that, If I feel brave when it stops raining, i will give it a try. I will keep everyone informed .thanks again
 
Hi,just been out and checked timing modulation its between 77 and 80 at tickover. after reading Wammers last post I set tickover at 128 and tickover settled steady at 750.5. will adjust static timing to drop nearer 50% when weather settles .Thanks all
 
128 at 750 rpm sounds pretty much spot on.

Modulation afterwards? Although modulation is mainly pump and chains it is tweaked by fuel pressure and (I think) a few other things such as temperature. Check lift pump in How To before playing with the pump position. If idle OK at 128 then do not touch the top of the pump! It is a bit high but not obscene.
 
Hi, had a good look at pump yesterday, no signs of tampering at all ,security bolt not damaged and no markings on side of pump.so i am sure nothing has been touched.Will check lift pump berfore I do anything else. thanks
 
Grrrrrr said:
128 at 750 rpm sounds pretty much spot on.

Modulation afterwards? Although modulation is mainly pump and chains it is tweaked by fuel pressure and (I think) a few other things such as temperature. Check lift pump in How To before playing with the pump position. If idle OK at 128 then do not touch the top of the pump! It is a bit high but not obscene.
Click to expand...

Timing is adjusted by fuel pressure on VE mechanical pumps. But EDC pumps use an electrical solenoid for this purpose. Timing is adjusted by the ECU by modulating the timing solenoid subject to point of injection signal received from number four injector being compared to signals from CPS. That is the modulation being measured by Nanocom. Anything below 50% and the ECU is correcting advanced static anything above 50% it is correcting retarded static. 50% is the null position of the solenoid.
.
 
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