Intermittent poor running

[decampos]

Every now and again the engine note will change from gloriously silky smooth to a more rigid and rhythmic drone with sluggish performance to match. Today for example, after about 20 mins it started to display these symptoms. A few hours later I drove the car again and the problem was completely gone.

It sounds like what I imagine not running on all cylinders must sound like but why? Any idea what's causing this frustrating occasional problem?

Car is stock 75 Csi apart from a recently installed electronic ignition but the problem has been rearing its ugly face way before I put that in.

Any help very much appreciated.

 

[Honolulu]

Frequently mentioned poor running problem for CSi is the trigger points in the distributor body... need to soak them in cleaner...

 

[decampos]

Thanks four your reply Honolulu. Last time I looked, that looked pretty clean but I shall investigate. Would those needing a soak be consistent with the problem being intermittent?

Also, could this be a fault with the ECU?

 

[DerSchwede]

The ECU very seldom fails. Start with checking for air leaks and measure the coil and condensor plus having a look at the grounds (all 3 of plus the obvious one at the battery)

Cheers

 

[Stevehose]

check fuel pump and filter

 

[decampos]

Thanks for the replies chaps.

I'll look for air leaks and the grounds. Coil is only a few months old. There's no condenser. I changed the fuel filter about a year ago. Is there an easy way to check the efficacy of the fuel pump?

Many thanks
Ben