Fiat 1.2 Hunting / Revving poor idle FIXED SOLVED

Filing the mating surface of the manifold fixed the uneven idle this engine was experiencing, I suspect the car had ran low on coolant for one reason or another and this is what caused the block to get so hot and allow the manifold to melt and pull the fasteners through. Thus compromising the seal of the inlet port gaskets.
I'm currently waiting for a new metal coolant pipe to arrive so that I can finish this repair off and draw a line under it. the coolant pipe was rotten and started leaking whilst I was diagnosing the problem. something else to keep an eye on with these engines, it runs along the front of the engine underneath the exhaust manifold and connects to the back of the water pump.

[@tonwempe6998]

thank you, this helped me a lot !
after removing the manifold the problem was easily fixed

[@co0ter1]

Fantastic. Please subscribe, I might be covering some other jobs on these cars in the future.

[@W15Garage]

Valuable information!!! Thanks!

[@ryansabapathy2666]

👍good job brother

[@houditv]

Awesome info, thanks a lot

[@fabriziosantini7102]

Ciao! Facendo la traduzione su Google ho capito che hai spianato il collettore di aspirazione per farlo diventare uniforme e hai poi messo delle rondelle esternamente con i dadi per fissarlo mejo. Ti perdeva aria dalle guarnizioni?

[@co0ter1]

Correct, excessive heat distorted the plastic manifold.

[@bonkeydollocks1879]

Could well be my problem, brilliant, what did you do in the end? Put washers under the nuts? Are they 13mm

[@co0ter1]

I sanded the mating surface flat, took the tubular spacers out and reduced their length with a grinder. Fitted the manifold back with very thick washers.
Yes, M8 nuts. 13mm head size.

[@bonkeydollocks1879]

@@co0ter1 I did check mine, they haven't pulled through but thanks for the info, much appreciated 👍🏼

[@co0ter1]

@@bonkeydollocks1879 what's it doing, hunting?

[@bonkeydollocks1879]

@@co0ter1 surging, very slight rough idle,. I put on a new throttle body gasket and manifold reface where the throttle body sits, it was a bit misshapen, new precat 02 sensor , and my obd reader bought up a MAP sensor code, had new map sensor seems about 95% ok but compared to my wife's identical car it's just not quite the same, not quite as crisp but loads better

[@eoghanhennessy443]

Engine was over heated distorted manifold common