Engine Running Sluggish

[InfernoPaul]

I have just recently fitted a new manifold and de-cat exhaust system to my car and now when i turn it on to warm up it sounds like the engine is struggling like its running lean. As soon as optimum temperature is reached it runs fine again.

Has anyone else had this problem, or know where i can get a lambda sensor fooler from???

 

[1hpclio]

Have a look at your fuel trim, it will tell by how much percentage ecm is over or under fuelling...

 

[bozothenutter]

lambda?
could be the lambda heater circuit has gone bad, mine did and only ran fine when warm