Bloody modulation

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Flossie said:
Figured out the idle, touch screen press point was off sync, nano is a bit like that. Increased from 128 to 130 which has upped it about 50rpm. The idle fluctuates still. I've done a 6 minute video showing things but forgot to press record until it had been running a while. I've revved it up occasionally, revs are sluggish to return and the idle dips below 750 until it 'catches' itself.
When it's cooled down I'll get some more data of other stuff.
Edit- bloody video won't upload:mad:!!
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The revs are supposed to be slow to drop but if it still drops below 750 when you lift off,. it's looking more and more like worn chains and/or FIP.
 
Datatek said:
The revs are supposed to be slow to drop but if it still drops below 750 when you lift off,. it's looking more and more like worn chains and/or FIP.
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106k on the clock and knackered though?
Got insurance ,starts from tomorrow. I'll take it for a short blast up the road to see if it runs ok and abs light goes out, if not, cancel the MOT.
 
Chuck it all in and blast it through. Like Data says they do betterer with more than half a tank. Brim for MOT would be sensible, once the redex is run through and gone.
Agree with the pump top, I wouldn’t touch it yet, I think your Nanocom is leading you to conclusions without precedent. You’ll end up like Kermie :eek:
 
Flossie said:
106k on the clock and knackered though?
Got insurance ,starts from tomorrow. I'll take it for a short blast up the road to see if it runs ok and abs light goes out, if not, cancel the MOT.
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This modern diesel is too thin in my opinion and wears them more because it provides less lubrication.

I agree with datatek, don't touch that pump top. That won't affect the running with cold as the idle will be the same hot or cold. From Nanocom you shy be able to see fuel temperature from inside pump. Chains will stretch even more when hot so why that would affect it cold I don't know.
 
Yes, egr blocked off, I did try unplugging the MAF When, unknown to me at the time, modulation was 80+%,
Not done it since modulation at c50% though.
 
Flossie said:
Yes, egr blocked off, I did try unplugging the MAF When, unknown to me at the time, modulation was 80+%,
Not done it since modulation at c50% though.
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See what happens. My reasoning is fuelling will be slightly asjusted for air temperature in the pre-EGR using IAT but this is preset to something silly in the EGR model and it uses the MAF reading instead.
 
Grrrrrr said:
See what happens. My reasoning is fuelling will be slightly asjusted for air temperature in the pre-EGR using IAT but this is preset to something silly in the EGR model and it uses the MAF reading instead.
Click to expand...
I have a pre egr engine in my 2000 P38 but no wiring for IAT but I do have MAF I had bad running once when MAF sensor packed in. The great wammers helped sort it for me and explained how it all worked.
Right then, on EGR equipped cars IAT is a low preset in the ECU. ECU relies on MAF for running air temp readings. Normally if you have EGR fitted but disconnect the vac pipe to EGR valve car will run normally without issue. However EGR only runs at a steady fairly lightly loaded road speeds. It does not work at idle or on acceleration or when the engine is under load. If the MAF has gone duff and is feeding crap to the ECU the ECU may think EGR is operating and prevent high load fuelling. The ECU will only allow fuel to be injected that can be cleanly burned by what it thinks is the oxygenated air present in the cylinder. If the MAF is telling the ECU the airflow has dropped as it does when EGR is active, then that will cause your problems. If you run the car with MAF disconnected in your case the preset will be used for IAT. This may slightly change fuel usage as the fine metering adjustment extrapolated from IAT/ fuel temp and engine temp will not be as fine. Fitting good MAF is best option.
 
Datatek said:
Inlet Air Temperature Sensor, only present on pre EGR/MAF cars. Not relevant on yours.
A duff MAF can certainly affect running. They run fine with the MAF unplugged, may smoke a bit on acceleration and use a bit more fuel.
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Just trying to button it all back together now. In between other stuff.
Should I fire her up before disconnecting the MAF plug or do it before starting?
 
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