General Dufff EGR?

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General Dufff EGR?

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Nov 28, 2010
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Location
ellesmere port
Afternoon

I have been to Nottingham and back each day this week with work. last night on the way home sitting at 80mph with the cruise control on, i noticed the power dip, and i didnt have the power to accelerate.

I have cleaned the Map/Maf, i tried to get the EGR off this morning bu couldnt get two bolts underneath off(n) has anyone got any tips for these two bolts?, i cut my allen key down to try an get a turn but still couldnt.

Anyway im guessing my egr is stuck open or dead (i hope not!), theres no codes showing on my fault reader, i want to use my Multiscan, but i need to find the software to tell me laptop the USB is a COM Port:bang::bang:

Shes been running like a dream aswell

Paul:worship:
 
the way I always do it Paul is not to undo those two bolts but to undo the pipe lower down if you follow corrugated pipe is a clip to undo with small allen bolt watch out for metal washer , when putting back on just slightly tighten those two bolts which are easier to undo when egr off..anyway just slightly tighten and check pipe lines up before final tightness, little copper grease helps hold the washer inplace is little awkward putting lower pipe clip on but I find much easier than those two bolts ..you may have done it by now but also remove two bolts on fuel filter gives more access and careful not to damage any tubes on black fuel box thing near egr also worth cleaning map sensor as more room and only 10 minutes extra time..put the 3 bolts through egr when putting back on as they are too long to fit if not doing that way
 
thanks guys, i got home from work and got right onit!,i re-cleaned the MAf and Map, then i checked the EGR with Multiscan Actuators, gave it a good spray etc, seems to be moving freely, checked the earth stud to the ECU cleaned it.

Only code showing up is P0235 supercharging pressure, i have checked the pressure boost switch that all works. i need to find out what is boost pressure sensor A circuit malfunction actually is.

It used to do it when stilo73 owned it, when i got it i seemed to have sorted it an been fine for months. it normally happens pulling away in 1st or into 2nd the power goes. this is completely different, plodding along at 80 on c/control an it lost power. i hope its not the turbo gone.

Not sure to start a new thread if i dont find a thread about "boost sensor A circuit malfunction"?

:bang::bang::bang::bang::bang::bang::bang::bang::bang:

as much i as love her, i cant afford to be spending over a grand in 10months on her! and now some more! its the only bloody part which isnt new!
 
probably passed maximum pressure deviation from requested and actual boost hi or low? or passed a boost limiter?
a log of revs, desired boost and actual boost and vnt % will tell what the ecu didn't like.
also if you do a spot check with fes on barometric pressure and boost pressure with engine off but ign on to see if they are close(like 980mbar-1020mbar and both within say 10-20mbar of each other.
you may have to have a few goes or even start engine select parameters start log and then swich engine off but keep log going and then key back to ign on without starting engine, as I think the map will only run for less than 30sec with engine off(at least mine did when I was trying to test my map sensor)
have you had someone else start the car while you watch the turbo actuator, to see that it pulls in smoothly and quickly on start up and then with engine off it goes back out smoothly also, any jerkiness could mean sticky vanes which could lead to overboost,
 
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Many thanks sussexa, i will give that a go later. so i have done nearly 150mile with it like this an its no clearing! its driving a fully loaded tanker!.

I still need to see what is on this boost sensor A circuit malfunction, and what wires/cable go where and what to.

Many thanks again
 
probably passed maximum pressure deviation from requested and actual boost hi or low? or passed a boost limiter?
a log of revs, desired boost and actual boost and vnt % will tell what the ecu didn't like.
also if you do a spot check with fes on barometric pressure and boost pressure with engine off but ign on to see if they are close(like 980mbar-1020mbar and both within say 10-20mbar of each other.
you may have to have a few goes or even start engine select parameters start log and then swich engine off but keep log going and then key back to ign on without starting engine, as I think the map will only run for less than 30sec with engine off(at least mine did when I was trying to test my map sensor)
have you had someone else start the car while you watch the turbo actuator, to see that it pulls in smoothly and quickly on start up and then with engine off it goes back out smoothly also, any jerkiness could mean sticky vanes which could lead to overboost,

Attached are screenshots of the baro mbar and boost mbar, with engine off ign on

Boost Pressure-282mbar
Desired boost pressure-1300mbar

Baro pressure- 1016mbar
baro pressure signal- 4.018v

none of that makes any sense to me so if you could expplain please!(y)
 

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Doesnt sound right, try going into logging after youve selected barometric , boost, desired boost and try the procedure i mentioned above.
The baometric sounds right if your around sea level, the desired boost at ign on should only be around 998-1000mbar i think so no reason you should have got 1300mbar desired.
Try an actial log , you can record and then playback or pause etc the log( or upload as excel file)
Ill see if i can find an old log of a duff map sensor.

ok all I could find were running logs like this one (read about 70-80mbar high at idle and not running also and about 100-150mbar high at top end which was leading to a low maf reading and hence underfueling at top end nothing noticeable on road but found during logging during tuning)
fitted new bosch map sensor and reading went straight to within 2mb of barometric)
don't worry about desired boost it is read from a map so wont necessarily match barometric like I said idle or ign should be desired boost 998-1000mbar)
 
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after a painful time trying to get my fes to record a graph was a pain kept on bombing me out, using the free version of multiscan i finally got a graph!(y)

Still dont know what they are or mean, if you can put some light on the graph (attached and the readings) i would be very thankful!.

if its a map sensor ill have to get one first thing! im back and to, to Nottingham this week again! gonna be fun. 220mile round trip

Paul:worship::worship::worship:
 

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If that is driving around (as you wouldnt see that sort of desired boost parked up no load) then it looks like map sensor is dead as it should follow desired to some degree, even if there was a burst intercooler hose it should stil be above atmospheric.
Anyone close to you that you can swap map sensor with before buying one?
I think theyre around £30-40.
As for describing the graph
The 1013 atmospheric is just ambient air pressure and will vary daily with weather and altitude, the desired boost pressure is calculated from revs and fuel injected quantity(which is calculated from pedal position and revs)
So usually there is only boost pressure if you are pressing pedal and under some load (accelerating)as you lift off accelerator desired boost will drop to 1000-1100mbar
You can double check with just boost pressure and boost pressure mv and rev car or drive if result is a flat line like before probably dead(just incase check connections on plug(soray clean both halves and reconnect)
Only other thing are you 100% sure your in right program in fes
 
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Thats great, i have just been looking at the graph, thinking about the Map!, this parts still a learning curve for me using the software!. will normal LVW/Part Co/ Andrew Page etc motor factor will sell a map sensor?

i have only have a spare MAF! (n), it was clogged full of crap when i cleaned it!.
i will get one tomorrow and report back.

Thank you again for your help!(y):worship:

Paul
 
Its quite a hostile environment that the map sensor sits in, see how it lasts first, i got a copy cheap and it lasted probably 6 months(mine has even more hostile environment than most) others have had issues straight away others have lasted years seems a bit of a lottery with copies.
Do same checks when new map sensor is on and you have baseline data for future issue.
 
Morning

Sorry not been on to update. or have a look at whats going on been a busy couple of weeks in work an home.

Update is my Map from euro car parts never turned up in time, so bought one from Andrew Page. put it on and vvrrroommmm, turbo kicked in the amount of crap that came the back was a alot!

Any she is back to running like a dream, fuel comp has gone back up, Nottingham and back twice last week and Carisle and back last weekend never missed a beat.

Big thank you to all that helped, i will upload a screenshot of a working MAP Graph to help others to test theres!

Paul
 
Morning

Sorry not been on to update. or have a look at whats going on been a busy couple of weeks in work an home.

Update is my Map from euro car parts never turned up in time, so bought one from Andrew Page. put it on and vvrrroommmm, turbo kicked in the amount of crap that came the back was a alot!

Any she is back to running like a dream, fuel comp has gone back up, Nottingham and back twice last week and Carisle and back last weekend never missed a beat.

Big thank you to all that helped, i will upload a screenshot of a working MAP Graph to help others to test theres!

Paul

Do you work in the motor trade because i thought only trade could order from Andrew Page?

Phil
 
Morning Phill

Not to sure to be honest. i have been in two and had no problem, but i did notice on the invoices that it said "Trade Discount". i work for a company called Autocoding Systems nothing to do with the motor trade but everywhere i go. they always think and ask if i do because my workwear say "Autocoding Systems"

Comes in handy sometimes!

Paul
 
Glad you got it sorted.
Ill look back as im sure i had some simple multimeter resistance checks accross the pins on the map sensors( reading low and good one)
If you can measure your dead one im sure it will help people in future.
quote
did a quick spot check old and new measuring resistance on pins.(they might be usefull to someone one day as quick test)
new bosch 3 bar sensor(values with multimeter on 20k ohms scale, @ approx 15*c, *approx 984mb atmospheric)
------------new sensor --------- old sensor(read 60-70mbar high at atmos, 150-200mbar high at top end)
pin 1 to 2= 2.63 --------------- = 2.37
pin 1 to 3= 5.94 --------------- = 6.13
pin 1 to 4= 5.52 ----------------= 5.96
pin 2 to 3= 8.62 ----------------= 8.52
pin 2 to 4= 8.19 --------------- = 8.33
looks like I missed 3 to 4(or had no reading cant remember)
anyway if you check your old one(probably 3 pin?) and put resistance figures as I have above it would definitely help people spot check a dead map sensor.
 
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Morning Phill

Not to sure to be honest. i have been in two and had no problem, but i did notice on the invoices that it said "Trade Discount". i work for a company called Autocoding Systems nothing to do with the motor trade but everywhere i go. they always think and ask if i do because my workwear say "Autocoding Systems"

Comes in handy sometimes!

Paul

Glad your sorted now Paul :) When a MAP is faulty will it always throw up a fault message?

Phil
 
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