AAP sensor and rough idle

This site contains affiliate links for which LandyZone may be compensated if you make a purchase.
Thanks, apreciate it. Here are two new files I recorded from cold starting after car been standing in 2-3 deg celcius for 24 hours. the first is initial start up and then nanocom lost contact with ECU so I restarted the process with the second file and let it run for a while. The funny thing is that it always strts perfect and runs clean for up to 20 seconds or so before the uneven jerking begins. Let me know if there is anything off in these numbers, otherwise I will just replace the loom and the fuel temp sensor when they arrive and get back informing if there is any difference. Tomorrow i will ride a long day on highway so It will be interesting to see if it evens out when the engine gets time to really heat up. About the glow plugs, I don't know, I was thinking about it earlier and will replace them eventually also. I've run the test glowplugs with nanocom and havn't had any issues. It starts just by showing the key to it even now in the near zero celcius, so i guess they are working somewhat...

EDIT: is the Y605J / 4309 the right NGK plug for the TD5?
 

Attachments

  • Archive.zip
    23.9 KB · Views: 268
Last edited:
Seing the IAT reading which drops below the ambient temp as the engine runs and warms up and based on the fact that it doesnt missbehave with the AAP sensor unplugged i'd replace the MAP/IAT sensor cos that's the most suspect at this point a the default for AAP/T open circuit sends it to a stored IAT value in the fuel map
 
Awesome, thanks, Yeah I have only cleaned the MAP sensor but not replaced it. I will order one of those too.

EDIT: Should I buy the BOSH or have you any preferences quality wise? MHK100640 is the number right.
 
Update. I received my order and immediately replaced the MAP as it is a fast change. It did not cure the idle issue. The engine was warm though and there was some unevenness in the idle so I will see the tomorrow morning on cold start what it does. BUT it did make my throttle response a lot smoother. I had this small jerk just before the clutch engages fully when leaving from stand still and sometimes on going over to engine breaking too. I thought it was a symptom of the idel issue. But now it seems all gone. So likely they were 2 different issue. So it seems like the MAP was gone anyway. But I get back as soon as I have replaced the loom with the genuine I received and the fuel temp sensor.
 
Ok, so now I've replaced the injector loom too. Had the OEM britpart before and got the Genuine LR and I investigated them in detail to find out they are the exact same part from the same manufacturer in the smallest detail. Just the price differs over double. But I put the new one in anyway, also replaced the fuel temp sensor. No difference, the idle still stumbles and is uneven until the engine is very warm. Next I'll probably go for the glow plugs. After that I've done basically everything but replacing or remapped the ECU.
 
northernbobber said:
Next I'll probably go for the glow plugs.
Click to expand...
Nice one ...that's the first which you should have ruled out...
northernbobber said:
are the exact same part from the same manufacturer in the smallest detail. Just the price differs over double...
Click to expand...
about the similitude of injector looms please check out the plugs with magnifier, and the o-rings... i did that and it's a huge difference... though if nothing helps rule out the DMF cos that could be a reason too
 
Yeah true, forgot about them. The clutch and DMF was replaced by previous owner not too long time ago, but not really sure when. So that could also be the issue. I compared the plug and orings, identical and same manufacturer. So I think there are at lest three versions. replacement, OEM and genuine of which the two last are the same. I'll get back and report when I've received and replaced the glow plugs.
 
I finally received the glowplugs, now I need to find a moment of time to replace them. I was still thinking about the DMF, would that cure itself when the temperature gets high enough? or would it continue to fail the idle at any temp?
 
Replaced the glow plugs. Old ones were all dead whwn tested. The swap did not cure the issue though. We have disco ecu lying around from a disco p10 engine. I will swap to tgat just to see if that solves the idle issue to know if its possibly a mapping issue. Should not damage anything by that right?
 
Ok tested, it ran for 3 sek and then shut off, then not starting again even though cranking. Swapped back to my own ecu and runs like before with the lumping idle. Maybe alive tuning is the next step???
 
northernbobber said:
Ok tested, it ran for 3 sek and then shut off, then not starting again even though cranking. Swapped back to my own ecu and runs like before with the lumping idle. Maybe alive tuning is the next step???
Click to expand...
If you just plugged an ECU in without making it learn the security code with tester it's normal to cut out cos it became immobilised in the ''secure state" ...dont believe that you just can swap ECUs just like that without programming,

so you replaced the glow plugs which were dead but did you check if the new ones get feed? the warning on the dash is managed by the ECU and it comes on even if you have no plugs fitted or no relay... you should have felt a difference between all glow plugs dead and new ones as long as they get feed at least in the first minutes of theyr's post heat activity
 
Ok, I thought it takes the signal from the alarm ECU as I unlock it with the FOB. But it might just be as you said, would make sense. Yes I checked I got power into the plug cables. I could try to flash the ECU though if I would get my hands on the default map and see what that does. I think there was one at the nano com site. It should work too if I copy the map from a sweet running defender with p15 and install that in my edu right?
 
You can try again with the other ECU if you have nanocom, but go into "utility" - ''learn security code" and when it's confirmed try then... at least you can say that the ECU is ruled out regardless of the fuel map cos the map would affect it's power under load not at idle
 
A DEVELOPMENT!!! Ok, so what I did I used the nanocom MapWizard and downloaded a new map and installed it into my ECU. Now it seems to run good, some small hesitation when coming to halt before it finds a rather steady idle. My engine was warm to begin with so the whole ruth will be revealed within the following days. Also I have no jerking in getting off throttle and such anymore, it feels like a new car so far as i took a short spin around the block. It also accelerates like a new car, no turbo delay anymore, a light throttle and the turbo hits in immediately. I hope this solved the issue, I will give a report in a few days.

The map I used was svloe005-svtnp005
VEHICLE: DEF-110
GEAR BOX: MANUAL
MARKET: EUROPE
ECU PART NUMBER: NNN000120
DATE: 17-06-2002

I took the last with the NNN000120 as I assumed that is the one I have as I could not find the location for part number on my ecu. The other option would have been NNN500020, but after some research I think the one I used would be the correct for my 2002 HCPU 110. What do you think?

Anyway I could have gone wrong with something here damaging something?
 
As long as it runs you didnt ruin anything... you could have read the ECU type before the remap though or you can still do it in the settings - info section
 
Ofcourse, how stoopid of me, didn't occur to me I could use the nanocom for that. Just went out to check it and it reads part number NNN000120. And that can not be changed by the map I wrote there right? that is the hardware part number?
 
You must log in or register to reply here.

Similar threads

H
Rough idle - discovery 1
Replies
3
Views
380
hi_arshard
H
H
Base idle tuning - Disco 1 - V8 3.9L
Replies
5
Views
350
discool
discool
F
P38 DSE loss of power when driving
2
Replies
34
Views
2K
Tibo W
T
D
Disco 2 D2 AAP question
Replies
9
Views
829
sierrafery
sierrafery
JPaussie26
Land Rover wont Idle!
Replies
2
Views
623
marjon
marjon
Back
Top