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superdavelotus

EGR Valve/ Motor, how do you know it's working properly?

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Hi all,

 

I am trying to get to the bottom of my misfire problem since having my engine removed by PNM. I've changed the O2 sensors (which I knew wasn't them) to eliminate that problem, checked wiring. Then after working out that my problem starts from almost cold, I check the vac lines and one way valves. I found that the one on rear of engine was letting air pass both ways so fitted a new. Only to find that it failed as soon as I went out. So my problem is now focusing on the EGR valve as this pipe goes to that area. I suspect it may be stuck open. My questions are:-

1. How to I test this function? I think Espritmon can do this but don't know how?

2. Since engine was removed for a number of month, did the EGR need to relearn? If so is the a procedure I can do?

3. How easy is it to remove the plenum? I read the instructions and can understand them but there's a lot of stuff to remove! I have a set of plenum gaskets to hand should I need to remove the plenum.

My problem seems to happen about 20-30 seconds after start up, idle is rough and when checking my post O2 sensors the voltages drop off and I get my misfire. To add to my woes, I have no engine check light which doesn't help!

 

Regards,

 

David Walters

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There are a fair few bits to remove/disconnect to remove the plenum but it's not that bad. The worst is putting it back on while feeling underneath for the cable connectors.

Covered here with pics:

As for the EGR, provided neither of the tubes are leaking then just block them off. I just made up an alloy blanking plate and fitted at the centre join of the EGR tubes.

I don't remember any EGR function being part of the ECU learning, which is really only related with fuel trims etc.

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1 hour ago, redshift said:

I don't remember any EGR function being part of the ECU learning, which is really only related with fuel trims etc.

It's not, only fuel, idle, boost and knock are learnt.

There's quite a few ECM fault codes associated with the EGR system:

PO401 Exhaust Gas Recirculation Insufficient Flow Detected
PO402 Exhaust Gas Recirculation Excessive Flow Detected

P1404 Exhaust Gas Recirculation Sensors Position Feedback Sensor Beyond Open Limit
P1405 Exhaust Gas Recirculation Sensors Position Feedback Sensor Beyond Closed Limit
P1406 Exhaust Gas Recirculation Sensors Temperature Sensor Above High Limit
P1407 Exhaust Gas Recirculation Sensors Temperature Sensor Below Low Limit

If it's not working correctly then you should get a CEL and a fault code in OBDII-V8

 

 

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Espritmon does not work on the V8 so unfortunately that's no help here.

If your EGR valve is stuck open then I'd expect you would see elevated exhaust gas temperatures on the EGR temperature sensor data (or is this sensor only fitted on USA spec. cars?).

Have you datalogged the EGR dutycycle to see what's being commanded?

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I think all those error codes listed are fixed limit based, rather than adjusted values that are learnt?

In any case my EGR circuit is blocked off and very occasionally (like once a year) I get the P0401 "insufficient flow" code that auto clears after a few starts.

I don't think we ever got to the bottom of whether all these EGR parameters are part of the non federal ECU. I was told that I would not see a P0401 code as I have a EU car........

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If it helps, have a look at the code on your ECM:

Single Plate Clutch UK & European A918E0021S
Single Plate Clutch USA A912E0022K
Twin Plate Clutch UK & European A918E0282K
Twin Plate Clutch USA A918E0283K
Twin Plate Clutch European Federal A918E0285K
Twin Plate Clutch UK & European V8-GT A918E0351K
Twin Plate Clutch European Federal V8-GT A918E0352K

I would suggest that if it is a A918E0285K then it should work the same as a US one?

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Right guys, it appears I've gone on a wild goose chase. It appears that I don't have an EGR valve. So what the crankcase breather going to under the plenum and why is my engine blowing non return valves in about a minute? The last time I put a new valve on last night, I did not boost the car, only ran it under 2000RPM.

Note, I have no errors codes whatsoever.

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5 hours ago, superdavelotus said:

Right guys, it appears I've gone on a wild goose chase. It appears that I don't have an EGR valve. So what the crankcase breather going to under the plenum and why is my engine blowing non return valves in about a minute? The last time I put a new valve on last night, I did not boost the car, only ran it under 2000RPM.

Note, I have no errors codes whatsoever.

Hope this is not a silly suggestion but are you sure that they are the right way round?

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Hi Alan, 

thanks for the heads up. I took a picture before taking it off to make sure I didn't make that mistake. I've fitted two VW ones and they are the ones that have popped. The Lotus one arrived today so I fitted that. The only difference between two is that Lotus one says 'made in Germany'. Tried running it and after two minutes it starts playing up. I took pipe off and the valve still works (up to now). Weather is crap here to take it for a spin. 

Next job is to check the earth strap from engine to chassis followed by taking one of the cats off to see if blocked.

will keep you posted,

 

David

image.jpeg

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Dave, try leaving the valve open to the air on the plenum side (or put an extra bit of hose on and temporarily dump it into a Coke can or something). Bung the plenum hose up with a piece of dowel and a Jubilee clip. Just to see what happens?

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Hi Alan, I tried that last night when second valve failed. Bunged the hose up and left crank case to vent to atmosphere. After a minute misfire still happened.

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Have you datalogged it at startup to see if there are any odd values coinciding with when the misfire starts?

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16 hours ago, superdavelotus said:

I am trying to get to the bottom of my misfire problem since having my engine removed by PNM.

Dave. Trying to get back to the usual problem causing situation here. What has changed?

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Hi Alan, I thought I'd edited the company name out. I'd like to try and get to bottom of problem myself.

Anyway, I had new manifold studs, turbo oil and water pipes and obviously the engine was removed so therefore entire loom was disturbed!

I did speak to owner today who said he would take car back and look into problem and double check nothing had been missed. So fairness here and I am in no way bad mouthing and giving negative feedback.

I have spent a fortune on a lot of work in the last few months and quite frankly, I can't keep spending money for the sake of it. It's very easy for someone to say 'it's your O2 sensors, just put new ones in'.

i just need to find out what is causing this problem. If I had a figure to put it right 100% then as least I could make a decision. At the moment I am just replacing parts which is not cost effective.

Regards,

 

David

44 minutes ago, sailorbob said:

Have you datalogged it at startup to see if there are any odd values coinciding with when the misfire starts?

If someone could tell me how to do this then I'll give it a go?

I am using Dash Command on my iPhone at the moment only because it's convenient. I guess I need to use Gendan or similar to date log it?

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really hope you get to the bottom of this. Once my lumps out I will take a look at where this valve is and see what it's doing. I'm sure my mate will have a suggestion of stuff to try but it won't be until next week.

 

 

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Does anyone know what is replaced by a non EGR valve set up? There's nothing mentioned in service manual about this at all. Any V8 gurus out there?

I am trying to work out where my crankcase breather pipe goes to from rear on RH rocker cover that disappears under the back of the plenum on LH side.

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you just blank the pipes off.

in the random stalling link about I'm sure it's explained..... I've been looking at plenum removal gremlins !!

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Peter Maeers s/w is the one to use for datalogging as it gives the Lotus specific data as well as the generic OBD-II data.

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Thanks Derek, I have his software open as we speak. I need to work out how to use it though...

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I've managed to datalog my car and save the file. Anyone here a V8 guru who can read it for me?

I tried resetting fuel and ignition just to see if it made a difference but it didn't, so there will be some odd readings in there but that's later on.

OBDIILOG-05-03-16.csv

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From a brief glance the main thing that stands out is that there's often a bit difference between the fuel pulsewidths of each bank.

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On 05/03/2016 at 14:58, superdavelotus said:

I've managed to datalog my car and save the file. Anyone here a V8 guru who can read it for me?

I tried resetting fuel and ignition just to see if it made a difference but it didn't, so there will be some odd readings in there but that's later on.

Dave, was the car exhibiting the misfire when you took the log? If not could you log it before, during and after start up and through the misfire?

I've had a look through the one you posted. Let me know.

Cheers, Alan

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