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Discussion Starter · #1 ·
hello boy and girls

1.8t AUM golf

bought an aftermarket manifold and when i put it on i got a lumpy idle ive searched for everything and it is definitely the manifold causing the issue. me and someone else have logged the car and tried to change a few things in the ecu to get it to run smoothly but nothing, the closest we have got was winding the load right up but then we are maxing out all the parameters. we are lost. has anyone else had an issue with changing the inlet manifold for a larger after market one.

currently running a ko4
de cat
rear o2 sensor delete (properly mapped out)
sai delete (properly mapped out)
high flow fuel pump
and then the after market inlet manifold the volume is twice the size of the stock one

i put everything back to stock then changed each part back to aftermarket one by on and the problem comes back when the inlet manifold is introduced to the system

any input would be appreciated, its been pressure tested, smoke tested, all sensors have been changed car runs spot on with the stock intake manifold but rubbish with the larger manifold on and it leans out
 

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Discussion Starter · #3 ·
What other mods? Air mass dictates load, so you shouldn't have problems. Do you have logs?

these are the only mods i have done listed in the original message

the logs my guy sent me wont upload to this site for some reason i do have a link to nefmoto where they are on there if you can look at them on there.

 

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Discussion Starter · #5 ·
When is lambda reg coming on? 62*C? Tried unplugging the coolant sensor? Your MAF is oscillating at the same time lambda reg comes on.
I can get my lambda to kick in when I bring the revs up or it takes 4-5 mins to kick in. I’ve not tried the coolant sensor I’ll buy one today and see what happens. I don’t understand the logging. Hahaha
 

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VR6 GT35 4mo
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Your coolant sensor is working fine, but lambda reg is coming on because of coolant temp and from memory it's about 62*C. Could unplug the sensor to disable lambda regulation and see if that stops the hunting.

As I said, the manifold shouldn't make a difference to the map really, the MAF accounts for all consumed air.

Who did the map? Can send it over and I can check it out, often people are a bit out on definitions and it means lambda coding isn't always correct. Do you have fuel trims (block 32)?
 

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Discussion Starter · #7 ·
When is lambda reg coming on? 62*C? Tried unplugging the coolant sensor? Your MAF is oscillating at the same time lambda reg comes on.
Changed the coolant sensor still no change.
Your coolant sensor is working fine, but lambda reg is coming on because of coolant temp and from memory it's about 62*C. Could unplug the sensor to disable lambda regulation and see if that stops the hunting.

As I said, the manifold shouldn't make a difference to the map really, the MAF accounts for all consumed air.

Who did the map? Can send it over and I can check it out, often people are a bit out on definitions and it means lambda coding isn't always correct. Do you have fuel trims (block 32)?
it’s just got a standard map on it I have a bloke called Otto looking into it.
 

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VR6 GT35 4mo
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I said your coolant sensor wasn't the issue. I thought you said you've deleted the SAI/rear O2 - is that you've physically deleted them but not in software?

So do you need help or not, I'm confused?
 

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Discussion Starter · #9 ·
I said your coolant sensor wasn't the issue. I thought you said you've deleted the SAI/rear O2 - is that you've physically deleted them but not in software?

So do you need help or not, I'm confused?
[/QUOTE



unplugged it and no change
I said your coolant sensor wasn't the issue. I thought you said you've deleted the SAI/rear O2 - is that you've physically deleted them but not in software?

So do you need help or not, I'm confused?
i unplugged the coolant sensor and still no change. Yeah it’s been deleted from the software. Literally if I put the original manifold on the car runs fine but as soon as I change it for the after market one it runs rough again.

yeah I need help o want my car
I said your coolant sensor wasn't the issue. I thought you said you've deleted the SAI/rear O2 - is that you've physically deleted them but not in software?

So do you need help or not, I'm confused?
yeah sorry I do need your help.

so I left the coolant sensor unplugged and still no change. When I change the manifold for the standard one it runs fine but as soon as I swap it for the aftermarket one it runs rubbish again. The Sai and rear lambda sensor have been deleted from the software.
 

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Discussion Starter · #11 ·
If you want to send the software over I can look at it. You'd said it's got a standard map on it, that's all.
it wont allow me to send the bin files that oto has left on my computer do you have an email i can send them to? i have 4 on my laptop but i have no idea what ones he has changed if he has adjusted anything.
 
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