Hi All

 

I am new to this site, i have a 2007 Ford Fiesta 1.6tdci

I have 2 questions.

 

1. what will the impact be on my car if I take out the Cat ( well I think it is the cat) ( if you stand IN front of the car, under the turbo there is a huge silencer or the cat). will it give more power and be lighter on diesel.

2. there is times where when my car idle its like there is a miss and you can see the revs going up and down but not extreme just little bit, but there is no power issue or starting problem, mostly doing it when she is cold, but sometimes even when normal temp is reached. 

can it be glow plugs or a vacuum leak? or diesel filter that is dirty. 

 

Thank in advance 

Can’t answer much of the above. What I can say is glow plugs are only on when cold. So if it falters on idle when hot you can’t blame that on glowplugs.     If fuel filter clogged you will notice it more when driving hard as that is when it needs sudden high fuel flow.    If you do change filter it can be very troublesome to bleed air out and get it running properly again - be warned. Took me all day on my 2007 1.6tdci . Obviously a garage can do it quicker.  If the car runs well I would be tempted to leave well alone. These are complicated and you could very easily end up worse off and wish you had not interfered with it

Ps, I know what you mean by that big wide bit of exhaust in front of the engine. I was never sure what it was because people seemed to say diesels of that age did not have a cat on.   And I know that car did not have dpf

1 minute ago, isetta said:

Ps, I know what you mean by that big wide bit of exhaust in front of the engine. I was never sure what it was because people seemed to say diesels of that age did not have a cat on.   And I know that car did not have dpf

It's definitely a cat.  Even the 90s diesels I worked on had cats fitted...many of them ruined by blown turbos dumping oil through them!   There was no MOT requirement to check for a cat on a diesel until very recently though, so when the cat was ruined, you could just fit a de-cat pipe.  Back in my 'naughty' days, I even checked with VOSA that a de-cat on a diesel would pass MOT...that was around 2012!  It was illegal, but not an MOT fail.

Anyway, to answer the question, having had several de-catted diesels, it makes no difference at all...  You get a little more turbo whistle but that's it, it won't give you more power and it won't give you better fuel economy.  I wouldn't bother nowadays.

Slight misfire is likely to be due to worn injectors, not worth the repair cost until they cause more problems though.