Northern Auto Tech - ECU and Blue & Me Repairs

General very rough idle

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General very rough idle

Tony123

Tony123

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Someone help me please before I put a lit match in my petrol tank +_+

My car has all of a sudden start to idle very rough, and when I'm driving I get to 3500 and I just get more noise out the car but no speed and the revs go up very slowly around here.

I have noticed a hole in my exhaust after the last cat on the flange will the cause my rough idling ?
 
ive just asked someone to make me a custom exhaust from the flexi joint back and he said he will do it for £250 fitted.

He said he will make it whilst im there...
One thing though he said he will de-cat it on the middle... will this this throw any warning lights for me ?
 
It shouldnt throw up any warning lights, it just will throw off the emissions which might fail an mot next time unless you swapped the system around
 
Tony123 said:
theres a lambda sensor just after this cat... Would this not flag up as being wrong ?
Click to expand...

not sure if its the same on hgts, but im sure when people put in the 4-2-1 manifolds and dont get another lambda sensor hole put in they just wrap up the 2nd sensor in foil and it works fine (i think its foil anyway)
 
JustAndy said:
not sure if its the same on hgts, but im sure when people put in the 4-2-1 manifolds and dont get another lambda sensor hole put in they just wrap up the 2nd sensor in foil and it works fine (i think its foil anyway)
Click to expand...

Ok thanks.. i shall ask someone who may know and would oyu say £250 is a decent price ?
He said hes making it there and then and i can choose how i want it and how loud ect ?
 
Tony123 said:
i think it is in stainless steal..
Click to expand...

Make sure -- most of the cost is the labour, so it makes sense to get it done in something that'll last the life of the car and still have resale value.

Tony123 said:
what would you say about de-catting ?
Click to expand...

If the cat is big enough (the rover V6 cat is said to be about the same size as a Cinq one but with much better flow) you'll not gain a lot by omitting it and it'll make MOT (let alone roadside VOSA inspections!) a lot easier.
 
fingers99 said:
If the cat is big enough (the rover V6 cat is said to be about the same size as a Cinq one but with much better flow) you'll not gain a lot by omitting it and it'll make MOT (let alone roadside VOSA inspections!) a lot easier.
Click to expand...

So do you think i should keep a cat on ?

Also with my car acting strange when reaching 3500 revs and gaining speed very slowly is this a fuel mixture problem or could it be the gear box ?
 
On the HGT, I would keep the underfloor cat and throw the precats. They only help emissions when the system is cold and waste fuel/power by blocking the exhaust flow when the system is hot.

If you want top performance you will need an exhaust manifold with tuned length primary pipes. Two decat pipes in place of the precats will be a close 2nd. To avoid ECU errors, keep the two precat O2 sensors.

Please dont junk the main cat. I hate following smelly modified cars where someone has just dumped the catalyst. It needs proper ECU tuning to get it running clean and then you cant easily put the cat back for MOT.
 
WhiteSei said:
On the HGT, I would keep the underfloor cat and throw the precats. They only help emissions when the system is cold and waste fuel/power by blocking the exhaust flow when the system is hot.

If you want top performance you will need an exhaust manifold with tuned length primary pipes. Two decat pipes in place of the precats will be a close 2nd. To avoid ECU errors, keep the two precat O2 sensors.

Please dont junk the main cat. I hate following smelly modified cars where someone has just dumped the catalyst. It needs proper ECU tuning to get it running clean and then you cant easily put the cat back for MOT.
Click to expand...

I dont mind keeping the cat on just this fella was gonna put a straight pipe on.
I got quote £140 for a new one :eek:

You any ideas on the problem im having when getting to 3500 revs ?
 
Just noticed with my car, when first starting it, you put your foot on the accelerator and the revs drop causing the engine to idle....
This has just blew all the exhaust paste i put on the other day.. anyone help me with the problem ? Its getting a lot worse
 
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