General Mifiring / Backfiring

[Keiran02]

Hi My Brava 1.4sx Seem's To Have Developed Some Faults Are They Related????

Firstly It Seems To Developed A Misfire In The Wet, It's Happened Twice Now I've Taken The Leads Off Sprayed Them With Some WD40 And Put Them Back On And It Improves! Also I Think My Leads Might Be Cheap And C***!!!

Secondly My Exhaust Seems Loud However I Can't Find A Blow And I Get The Occasional Backfire When The Rev's Come Down! And Then Idles Erratically (I Was Told It Might Be The Coil????)

Also My Fuel Efficiency Seems Really Bad Approx 17-20 MPG????

Coor This Car Might Send Me Mad But Still I'm Liking My Fiat

 

[jug]

replace plugs and leads first. coil failure results in running on 2 cylinders (very rough) so i doubt that is an issue.

 

[Keiran02]

Right Cool I'll Try That Thanks

 

[Keiran02]

Ok i replaced the lead's its running better however still appears to Idle Ruff,

 

[jug]

did you check condition of the plugs too?

the exhaust noise is also an issue, a leak will cause uneven low back pressure which leads to rough running and scavenging which wastes fuel. you need to cehck the exhaust system carefully, the flexijoint is a favorite place to leak.

 

[Keiran02]

Hi The Plugs Were Ok (A Little White With Some Light Carbon Build up) I've Tried Blocking The End Of Exhaust And Spraying It With Leak Detector But Could'nt See Anything I Think I Might Just Take It To My Mate At ATS And See What He Say'a

 

[Keiran02]

Right After Spending An Hour Waiting At ATS I Got Bored And With My Washing Up Mixture I Found The Blow!!! Yay Even Better (I Think) It's The Joint Between The Manifold And Down Pipe! So Am Going To Attempt To Re-Seal It Tomorrow Any Pointer's????

 

[jug]

use a new gasket