Low Rev Throttle Response, at a loss now!

This site contains affiliate links for which LandyZone may be compensated if you make a purchase.
sierrafery said:
If with that map made well by empire is still not good there is a problem with the engine or ancillaries: injectors, FPR, turbo or it's hoses , etc.. cos the management is all working well based on the log
Click to expand...

Well thats good to hear! So you'd be happy with that log? Do I still need to check the boost or is that ok now too?

To be honest its 100% better than when I bought it, something amongst the following changes had a positive effect:

Injector Loom and Gasket
MAP Sensor
Fuel Filter
Oil and Filter Change
Air Filter
Removed and thoroughly cleaned all earth points
MAF Sensor
Changed Throttle Loom
Changed from 3 Track to 2 Track throttle
ECU chip set back to factory

Thanks again for yours and everyone else's help to date, it may well not be a done deal, but thanks anyway!
 
the log shows that the sensors are working well just that based on the MAP and MAF readings which are presumably accurate the boost is low for some reason
 
I tell you that the boost is low based on the log you can't check more just that at this point i dont know the reason. Squeeze the turbo/intercooler hoses, if they are soft you should replace them first with silicone.
 
Normally at 9 threads left on the rod untill the locknut it should go to overboost or at least close to 1.4 bar if everything is OK and the management seems to work well
 
sierrafery said:
Normally at 9 threads left on the rod untill the locknut it should go to overboost or at least close to 1.4 bar if everything is OK and the management seems to work well
Click to expand...

Wound in to 5 threads...no difference at all and no overboost or limp mode. I will say that is palpably worse when the MAF (yes MAF) is connected. When connected, bunny hops and drives rough.
 
*** Update ***

@sierrafery @resto_d1 @boguing

Good News Gentlemen!

Cold start this morning, drove smoothly with no bunny hopping. Gear changing and acceleration were flawless. Pulled like a train and when asked, she accelerated as expected (not a Golf GTI!). Pulled up the hill to the farm just nice, only having to change down to 2nd gear on a bend to prepare for tractors or horses.

MAF is disconnected and cable tied out of the way. I have read and re-read the treads and often heated debates about whether this is relevant or not. All I can tell you is that it makes a VAST difference to the performance - fitting the new MAF sensor merely made her sluggish, unresponsive and prone to 'hopping'.

Wastegate Actuator is at 10 threads (I may play with that but thats my default for now).

So, on balance I am happy now. Though I am conscious Landy performance is like the weather and I will inevitably be back, I want to thank you all for your input and the time you took to read the Nano logs. Top bunch!

So whats next.......oh yeah, water ingress....seat padding...etc....etc....etc..... ;)
 
Welcome mate - glad you got it sorted. Hopefully you can repay and tell me where the celebration box of random bolts go on my d1 build 😂.
Drive safe
 
tweedandbriar said:
1. Wound in to 5 threads...no difference at all and no overboost or limp mode. I will say that is palpably worse when the MAF (yes MAF) is connected. When connected, bunny hops and drives rough.
Click to expand...

tweedandbriar said:
2. fitting the new MAF sensor merely made her sluggish, unresponsive and prone to 'hopping'.
Click to expand...

tweedandbriar said:
3. Wastegate Actuator is at 10 threads (I may play with that but thats my default for now).
Click to expand...
tweedandbriar said:
So, on balance I am happy now.
Click to expand...

I hate to ruin your joy but based on the quoted parts you have not much to be happy about unless you dont know how a well running Td5 should behave cos there is something wrong with your engine:
1. not going to overboost below 9 threads means that the boost is not rising enough for some reason
2. as long as the MAF sensor is new and genuine(unless it's faulty from factory which is unlikely) it should be technically impossible to run better on open circuit default that's a fact so something is wrong there too in this case with the management... unless the EGR's electrical hardware was left connected which as long as it's bypassed it's silly cos it creates load on the MAF circuit without any benefit/
3. as long as it doesnt go to overboost at 5 threads left at 10 it should have even less boost or the boost simply stops at a point and doesnt grow above that limit no matter what you do while the watsegate doesnt open at all, clamp the pipe to the valve and if no overboost then it's definitely low on power, i've seen defender with no remap just a boost clamp on the MAP sensor which boosted up to 1.7 bar on the gauge at 7 threads left on the rod...that one was running well

So, in conclusion, if you are happy with it i'm happy for you but your vehicle is far from being OK.
 
Last edited:
sierrafery said:
So, in conclusion, if you are happy with it i'm happy for you but your vehicle is far from being OK.
Click to expand...

I have read these threads with interest - very polarising thoughts on the efficacy of the MAF on a 10p engine, particularly when the EGR is blanked off, as it is in mine.

MAF 1
MAF 2

I do understand the issues you describe re' low boost, and will investigate that further. All I can say is that any further increase in performance would feel cumbersome. I have driven plenty of Defenders over the last decade or so, predominantly when working at Glastonbury Festival (not my day job!). This doesn't feel that dissimilar to those.

I'm not sure if I agree that its "far from ok"...but agree that there is still work to do.
 
sierrafery said:
I hate to ruin your joy but based on the quoted parts you have not much to be happy about unless you dont know how a well running Td5 should behave cos there is something wrong with your engine:
1. not going to overboost below 9 threads means that the boost is not rising enough for some reason
2. as long as the MAF sensor is new and genuine(unless it's faulty from factory which is unlikely) it should be technically impossible to run better on open circuit default that's a fact so something is wrong there too in this case with the management... unless the EGR's electrical hardware was left connected which as long as it's bypassed it's silly cos it creates load on the MAF circuit without any benefit/
3. as long as it doesnt go to overboost at 5 threads left at 10 it should have even less boost or the boost simply stops at a point and doesnt grow above that limit no matter what you do while the watsegate doesnt open at all, clamp the pipe to the valve and if no overboost then it's definitely low on power, i've seen defender with no remap just a boost clamp on the MAP sensor which boosted up to 1.7 bar on the gauge at 7 threads left on the rod...that one was running well

So, in conclusion, if you are happy with it i'm happy for you but your vehicle is far from being OK.
Click to expand...
Could the ecu not recognise the amount of boost if maybe a boost box had been fitted? I don’t know if one is fitted to the ops car but it was a popular mod on remapped td5.
 
tweedandbriar said:
I'm not sure if I agree that its "far from ok"...but agree that there is still work to do.
Click to expand...
My statement was not about it's driveability as you can feel well at 1.2 bar boost too if you dont want a race car i can just reformulate that it's far from OK power/boost wise as long as it doesnt go to overboost starting from 9 threads left on the rod or in your case at 5... or if you clamp the pipe to the valve and still no overboost means that the wastegate is useless then it's very far from OK ;)
johnlad said:
Could the ecu not recognise the amount of boost if maybe a boost box had been fitted? I don’t know if one is fitted to the ops car but it was a popular mod on remapped td5.
Click to expand...
Yes, the ECU would not see it if that was the case but those boost clamps are usually set to 4.5 or 4.7V which is equivalent to around 1.3 bar boost as to disable the overboost default while i didnt see more than 1.15 in any of those logs also if the MAP is clamped the high physical boost creates higher sucction too up to 650 MAF reading while i didnt see much above 400 in those logs so based on the readings that engine has not enough power... it would have beed understandable to run better with MAF unplugged if a boost box was fitted but then the MAF reading should have exceeded 680 for the turbo overspeed protection to kick in which is not the case here

... very strange indeed
 
Last edited:
sierrafery said:
Even then at 5 threads left on the wastegate rod it should overboost at 2000rpm under load if it has enough power ;)
Click to expand...

Thought I would give an update - I hate it when threads just fade away without a conclusion....

I've put the 'stock' ECU chip in and the old girl runs 'fine', yes not the power and grunt it had when the mapped chip was in, but much more pleasant to drive and not spewing copious amounts of black smoke out when I accelerate. I suspect the mapped chip was hugely over-fueling(?)

@sierrafery Yep, you’re correct of course, boost is low, it seemed to be improved (though yet to run the Nano on it to confirm, later today hopefully) All I did was remove the turbo hoses (they are silicon) and clean up the joints and re-tighten. Also, oddly, it runs 'fine' with the MAF reconnected - this definitely was not the case with the mapped which.


So, given that changing the length of the wastegate actuator doesn't seem to make a difference in terms f boost, where from I go from here?

Cheers...
 
You must log in or register to reply here.

Similar threads

B
Disco 1 Part stc 4389 Throttle potentiometer for Disco 1 300tdi EDC 97
Replies
7
Views
835
lynall
L
Mr K
Freelander 1 Lumpy and doesn't want to rev when cold
Replies
2
Views
556
Mr K
Mr K
S
Series 3 SIII Diesel won't rev
Replies
10
Views
1K
series III
S
N
TD4 2004 throttle dead after clutch change
Replies
4
Views
1K
NDW
N
P
L322 Vogue 2006 4.4 V8 MAF/limp mode issues
Replies
9
Views
440
peterself
P
Back
Top