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Discussion Starter #1
Since temps went over the 20 degree mark my engine light has been impossible to keep off. P0401 ...removed plate ....problem solved....why would that be?
 
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Discussion Starter #2
Not a clue but I have the 3 small holes on one side and 4 holes on rectangle gasket and not had any engine light :)

So could it be something else in combination with gasket? Tuning box? Or slight pressure sensor misread that gasket makes it drop... Only thinking out loud as not sure what 401 is off top of head.
 
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P401 is insufficient gas flow on egr...

So try cleaning Pressure sensor as if it's slightly under reading combination of that and gasket could be throwing error.

Egr maybe getting a little sticky so adding gasket popping it just past point where throws error.

Suggest clean and lubricate egr and clean pressure sensor and re-try... If not maybe try the 3 hole gasket.
 

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Not a clue but I have the 3 small holes on one side and 4 holes on rectangle gasket and not had any engine light :).
Same here. Maybe that single hole is restricting that bit too much for the ECU'l liking.

Put the 3 hole type in.

All the best

Pub
 
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Thanks guys, EGR has been zapped in work in the electronic bath, lubricated and tested . Think a new MAP if the three hole plate fails...existing MAP is the original at 104k and think its one of the few parts that has never been replaced. It's been in and out a good few times and to me the sensor rod looks a bit swollen ?
 
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Other possible idea... maybe heat exchanger thing where exhaust gasses heat up coolant have over time become all blocked and gunged up... not be the first time that's happened.

I'd also guess although the restrictor gaskets improve flow in egr and into intake manifold they probably reduce flow in pipes a little which could help popping deposits elsewhere in pipe...

Could maybe suggest take both egr pipes off heat exchanger and fire loads of cleaner down it (carb/diesel intake or similar and see if much comes out... least it's a cheap thing to try :)

John
 

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Other possible idea... maybe heat exchanger thing where exhaust gasses heat up coolant have over time become all blocked and gunged up...
This is an excellent suggestion. it's what's always worried me about blocking the EGR completely. If I were ever to to it then it would have to be at the exhaust manifold rather than the in/out of the EGR.

Admittedly gases would no longer be flowing through the exchanger but I'll bet it would still block up to some extent.

In this situation though I think it's simply the case the single hole restrictor is reducitng flow a bit too much. If redoing the ECU map is an option why not have the EGR deleted, certainly no more EML then.

Good luck

Pub
 
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Discussion Starter #8
Other possible idea... maybe heat exchanger thing where exhaust gasses heat up coolant have over time become all blocked and gunged up... not be the first time that's happened.

I'd also guess although the restrictor gaskets improve flow in egr and into intake manifold they probably reduce flow in pipes a little which could help popping deposits elsewhere in pipe...

Could maybe suggest take both egr pipes off heat exchanger and fire loads of cleaner down it (carb/diesel intake or similar and see if much comes out... least it's a cheap thing to try :)

John
Project for next Thursday sorted (next day off) ...Cheers
 
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Discussion Starter #10
You could maybe even disconnect pipe at manifold and egr and throw cleaner down the whole lot with a tub under bottom end.... probs not a terrible idea to have whole lot cleared :)

Also any chance you have full version of FES/MES? As you could also operate solenoid in egr will it's not bolted on to see if moving properly.

I don't think it's single hole as iirc hole is bigger I think it's something else starting to be a problem and hot weather adds to problem just enough to throw error then removal of gasket adds just enough flow to pop error just back over the point where it flags an issue.. left long enough I reckon it would error without gasket as well.

;)
 
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Discussion Starter #11
Reading through again I do have a speedhawk tuning box , another possibility in the mix ? ...will try a different setting to see if it makes any difference! Currently set at 6 ...anything above my old engine struggles...:)
 
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Discussion Starter #12
Again may just add a little more uncertainty to mix or increase in airflow to match extra fuel chucked in (in weather when the air will be less dense) maybe the single hole (or restrictor gasket) just cant quite keep up with change in pressure ecu expects when egr opened :)
 
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