Rough Start up | Ph1 172

[Craig_B]

About a month ago I had fitted my Coilovers fitted, and the next day I drove over a raised manhole cover/drain

My cat (twin cat) hit the drain and it instantly started to run crap. Very loud as the exhaust gases were now coming straight from the manifold.

Now I've sorted the 'blow' with a new cat fitting kit it's been running fine except for on start up after the car has when standing (overnight) after about 30-40 secs it starts to dip in revs and seems to struggle. 30 seconds of that then it returns to normal idle and is fine to use.

I'm guessing at the Lambda? Maybe causing the problem, but MPG is fine at a average 32.9mpg.

Does my car have two lambda's? I only want to spend once to sort it.

Any ideas would be great!!!!

 

[Craig_B]

Any ideas??? Only does it on cold.

 

[Mar172]

You might be better off picking up a good second hand cat and try that.

 

[karol_SVK]

Only late 172 ph1 had two lambdas.
It looks more like an idle regulation problem to me.

Lambda data is been used just after the enviroment of the lambda sensor has the correct temperatures and in 30 secs it does not warm up enough I think.

good luck

 

[Craig_B]

Still does this

Had the cat looked at by an exhaust specialist and he said it wouldn't cause my car to do what it's doing.

Plugged it into a code reader and 0 codes found. And it's had a MAP sensor, oil change and plugs