CEL from high flow cats

Twinspark

Twinspark

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460
Wouldn’t relocating the sensors to read from the secondary cats solve the CEL? Someone over at ML did that with the larini units and had no issues.
 
FIFTY

FIFTY

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3,100
Zep said:
I think that’s a good idea, not least because wrapping the manifolds will be a pig of a job.
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Alright I'll order two rolls and see how it goes. I will report back if it works.

If it doesn't work then I might see if i can get the sensor remapped.

@Twinspark these custom cats will not be further modified. If the cells in these get knackered again I am buying something "off the shelf" likely larini
 
Gazcw

Gazcw

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FIFTY said:
The cats are in the location of the stock secondaries so yes downstream of the steering rack

How about starting off with just wrapping the section of pipe leading up to the cat from the flange and leave the manifold downpipe alone for now?

I agree with the notion of not wanting to back too much heat into the manifolds
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I looked at that pic quickly and thought, blimey he has skinny legs!
 
FIFTY

FIFTY

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Twinspark said:
Did you try using spacers/mini cats on the rear sensors?
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The discussion earlier in this thread is about the use of spacers and mini cats - They did not work.

I think it has the opposite effect to what we are trying to achieve in that the spacers/minicats cause the lambdas to be cooler and the error is being caused by the lambda sensors telling the ECU that the cat is not hot enough.
 
T

TimR

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I suspect that the cat needs to be closer to the headers (position of first cats in EU3 compliant cars)
Something you might need to reconsider @2b1ask1 with a custom build....?
 
ChrissGT

ChrissGT

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341
FIFTY said:
The discussion earlier in this thread is about the use of spacers and mini cats - They did not work.

I think it has the opposite effect to what we are trying to achieve in that the spacers/minicats cause the lambdas to be cooler and the error is being caused by the lambda sensors telling the ECU that the cat is not hot enough.
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Has the steelwool solution been discussed as well?

I had sportcats put on my GT, had a persistent cell after that. I tried spacers, but in the end found that adding steelwool in the spacer fixed the cell.

I just read the entire thread. I would suggest trying this solution. I had the exact issue (mine came on after about 40 miles) With the steelwool against in the spacer and against the tip of the sensor it stabilizes the temprature and slows down the air flow to the sensor.
Its a solution used by people going 100cell or catless as well. And as long you pass your yearly emissions there is no real world use for the secondary sensors.
 
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jasst

jasst

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2,316
TimR said:
I suspect that the cat needs to be closer to the headers (position of first cats in EU3 compliant cars)
Something you might need to reconsider @2b1ask1 with a custom build....?
Click to expand...
But on the Larini sports cats, the cat is in the same position as the secondary cat, and I doubt if they would do it if it was going to cause problems. I was speaking with Martin at Emblem, and he said they had been dealing with a car with similar probs, unfortunately Myles was on holiday, so I couldn't ask him what they did, and haven't had time since. I am thinking about putting my factory cats back on, and seeing if this clears the prob, if it does then I will know its the sports cats causing the problem.
 
T

TimR

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2,731
jasst said:
But on the Larini sports cats, the cat is in the same position as the secondary cat, and I doubt if they would do it if it was going to cause problems. I was speaking with Martin at Emblem, and he said they had been dealing with a car with similar probs, unfortunately Myles was on holiday, so I couldn't ask him what they did, and haven't had time since. I am thinking about putting my factory cats back on, and seeing if this clears the prob, if it does then I will know its the sports cats causing the problem.
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Interesting - I haven’t really looked at the Larini option. Too rich for my blood!
 
Mr S

Mr S

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Gazcw

Gazcw

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jasst said:
But on the Larini sports cats, the cat is in the same position as the secondary cat, and I doubt if they would do it if it was going to cause problems. I was speaking with Martin at Emblem, and he said they had been dealing with a car with similar probs, unfortunately Myles was on holiday, so I couldn't ask him what they did, and haven't had time since. I am thinking about putting my factory cats back on, and seeing if this clears the prob, if it does then I will know its the sports cats causing the problem.
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Is it Larini sports cats causing your problem? I was going to push the button over winter for mine. If I am going to have to deal with cel all the time I may not.
 
jasst

jasst

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2,316
Gazcw said:
Is it Larini sports cats causing your problem? I was going to push the button over winter for mine. If I am going to have to deal with cel all the time I may not.
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No, mine are custom made partly by previous owner and partly by my local exhaust fabricator.
 
Twinspark

Twinspark

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460
Gazcw said:
Is it Larini sports cats causing your problem? I was going to push the button over winter for mine. If I am going to have to deal with cel all the time I may not.
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Those are said to be fine, allegedly the units they use are HJS Motorsport ones (200 cell).
 
T

TimR

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2,731
So it seems it’s possibly a twofold issue..
  1. the cats don’t get enough heat....( too far from motor)
  2. the cats are be of questionable quality...
 
FIFTY

FIFTY

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3,100
I spent top dollar on the cats from a reputable supplier after a huge amount of research and advice taken from various parties
 
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