Check emissions light

Wayne172

Paid Member
Hi I replaced the clamp that joins the cat to the manifold this afternoon. Started the car and a few minutes later the 'check emmsions' light has come on. I have gone back under the car to check the lamba sensor is connected ok and cant find any issues. This light has never came on before. Any ideas? Just to note I am running a scorpion de cat and cat back exhaust.

Thanks
Wayne.
 

RSRowe

Paid Member
Maybe it's just coincidence. Reset it and see if it comes back on.

I have a scorpion decat on mine and it only ever comes on if I'm on the motorway doing 50mph through the averages. When I'm busting around town it's fine.
 

Wayne172

Paid Member
Thanks for the reply. I'm gona run a fuel cleaner in it and give it a good run. Read through a few posts and seems a common issue. Just strange how it come on after I'd had the cat off to change the clamp
 

RSRowe

Paid Member
Lambda sensors do have a tendency to being really sensitive when it comes to knocks and bangs.
Really doesn't take much to knacker one up if you're a bit heavy handed with the spanner.
 

Wayne172

Paid Member
I replaced spark plugs today as I had ordered them last week. When taking old ones out i noticed plugs 3 and 4 (drivers side) were a bit wet with un burnt fuel.
Would a faulty coil cause this?
Iv also noticed that it misfires at around 1.5k and revs drop and pick back up (when stationary)
For what it's worth the coils look old so I will replace these either way.
Someone has also mentioned that it might be worth checking that the lambda is nipped up all the way in the cat.
I'll have a look into this.
 

Wayne172

Paid Member
I now have sports cat back on a cleaned lambda sensor with cleaning spray.
Light is still on.
I have new coils coming tomorrow.
Sill question but would the fact that I have blanked off the breather pipe from throttle body that went to the butterfly valve effect the car? I have removed it completely so blanked off hose on throttle body.
 

Foxspeed

"the new red baron"
Moderator
if the second inlet valve is unplugged this can cause engine codes to come up...

also what about faulty injectors? may need to check for good spray pattern
 

Wayne172

Paid Member
I have an itg maxogen on the car.
So the butterfly valve on the right hand side of the car shouldn't be completely disconnected?

Yeah that is something I was also considering. Car drives ok.
 

RSRowe

Paid Member
You need to leave the butterfly plugged in. But if you're running a cone filter you need to blank that vacuum pipe.

What is the actual code?
 

Wayne172

Paid Member
So put the butterfly back in and connect the plug just blank it a the throttle body end and then the other end?

Not sure on codes. It's saying check emissions.
 

turkie172

Paid Member
I had an emission light activate on the motorway one day I knew nothing was wrong but I have a Renault clip and there is a test for the catalytic converter that runs the engine at 2500 rpm for about 2 minutes and must alter the ignition and fuel during that time to heat the CAT like a regen and calibrate the lambdas. Now since the car had a recent battery failure it looked like the injection computer had frozen and took me a while to get the car ignition right to clear the fault as it would not clear with ignition on or the car running so I stalled it to keep the red ignition lights on and now I know you insert the keycard and hold the start button for 5sec or so to get it there. Anyway without touching anything I cleared the ignition fault code ran the catalytic converter test the lambdas started to show live varying readings and the emissions warning disappeared. The wet plugs if they were not firing you would feel it the other thing would be if the injectors were stuck or leaking wetting the plugs and will destroy the lambdas. If you have just fitted the decat and the manifold is not genuine then there is no CAT's fitted I would expect the light to come on.
 

RSRowe

Paid Member
So put the butterfly back in and connect the plug just blank it a the throttle body end and then the other end?

Not sure on codes. It's saying check emissions.
Yes blank the pipe off the throttle body. You need to read the codes before you start replacing parts really.
You could be wasting your money
 

Wayne172

Paid Member
I had an emission light activate on the motorway one day I knew nothing was wrong but I have a Renault clip and there is a test for the catalytic converter that runs the engine at 2500 rpm for about 2 minutes and must alter the ignition and fuel during that time to heat the CAT like a regen and calibrate the lambdas. Now since the car had a recent battery failure it looked like the injection computer had frozen and took me a while to get the car ignition right to clear the fault as it would not clear with ignition on or the car running so I stalled it to keep the red ignition lights on and now I know you insert the keycard and hold the start button for 5sec or so to get it there. Anyway without touching anything I cleared the ignition fault code ran the catalytic converter test the lambdas started to show live varying readings and the emissions warning disappeared. The wet plugs if they were not firing you would feel it the other thing would be if the injectors were stuck or leaking wetting the plugs and will destroy the lambdas. If you have just fitted the decat and the manifold is not genuine then there is no CAT's fitted I would expect the light to come on.
Ok cheers for the advice. The car was mapped with decat on. But I put a sports cat on as it was a bit to loud for me. Anyway I only just the sports cat off as it was blowing from the joint to the manifold. So when I put the new clamp on I just stuck the de cat on. It was q better fit.
 

Wayne172

Paid Member
Yes blank the pipe off the throttle body. You need to read the codes before you start replacing parts really.
You could be wasting your money
Thanks for the advice. I'll see how I get on with reconnecting the butterfly valve first.
 

Wayne172

Paid Member
Just to update. I got myself an obd2 scanner from Amazon.
Hooked it up the car and came up with 1 fault code which was, P2075 - intake manifold.
I have cleared the light and it has not come back on again yet.
Any ideas what would of caused this fault code? Would an air leak cause this?
 

Wayne172

Paid Member
Iv had a look through the forum search for that fault code and it seems to point to the butterfly valve. As I had it disconnected it must of threw the fault. It have since put the valve back on and connected the jack plug and breather pipe.