Technical need help desperatley :(

[dmc123]

hey all.. new to the forum have a problem... 1.2 16v w reg punto

my mums car originaly had a head gasket failure, went in to be fixed.. came back all good and spot on.. but then developed a misfire.. went back to the garage 6 weeks ago.... they peed around saying it was the cataylic convertor... or the ecu.... they cudnt find the problem..... they changed the cat.. i went an picked it up 2day it wouldnt drive above 20mph... the cat was glowing red hot... and it had a horrible burning smell and smoking coming from the engine compartment and now it wont start because it misfires and its bloody hot!!!

 

[Moosey]

Seeing as how the cat converter is past the exhaust manifold collector, i can't see how that would cause a misfire in any way. Sound like bull**** to me.

Are you losing any oil or coolant? Judging by the timespan i would say it's a problem with the head gasket job they did. Did it overheat when it blew the head gasket? If so, the head may be warped, and if it wasn't skimmed (machined to be perfectly flat.) then that may be causing a leak.

What the smell like? Sweet smell, oily smell?

 

[dmc123]

thats what i thought... i have a rover 200 so ive had the head gasket stuff etc and i know the smells..... it doesnt smell like any of those things it just smells of fire tbh!!! i will go out and check the oil levels and the coolant levels....

 

[Moosey]

Ah.. the Rover K-Series, what an abortion of an engine..

If it's misfiring you could be chucking loads of unburnt fuel into the exhaust which is then burning in the cat, which in turn will destroy the cat.

If they've touched the cat while checking it, the smell could be gease/oils from their hands burning off when the cat gets hot.

 

[dmc123]

haha yes i agree... when it rarely runs right it is fantastic tho !! would rather have a rover t-series though!!! ah yess but it didnt turn the old cat red before when it was misfiring!!!! it could be i will go out and investigate again !!

 

[m20b25]

You may have a dropped exhaust valve or valves due to carlessness from the garage when skimming the head. Its worth checking this out

 

[Moosey]

haha yes i agree... when it rarely runs right it is fantastic tho !! would rather have a rover t-series though!!! ah yess but it didnt turn the old cat red before when it was misfiring!!!! it could be i will go out and investigate again !!

So for 15 mins after a new head gasket has been fitted, before it blows again?

You may have a dropped exhaust valve or valves due to carlessness from the garage when skimming the head. Its worth checking this out

Last time i took a 1.2 16v head in for skimming the machine shop said over the phone it HAD to be stripped bare. (Which it was anyway, i wouldn't have taken an assembled head in.) I think do to the valve size and head design you can't actually skim these heads with the valves in place. Not 100% sure on that though.

(My sig pic is a 1.2 16v head.)

 

[DaveMcT]

IIRC the valves on the 1746 were just proud of the head face. The 1242 is from the same design team so a good chance they do the same.

The K series was actually a great engine but Rovers management couldn't organise a p-up in a brewery so quality suffered.

 

[Moosey]

Yep, can't skim with valves in place:

It may be the coil pack. If you want, PM me your address and i'll send you one. I have a brand new one that i bought for a car and didn't need.