Need help with a strange problem

[Hussam]

Hello everyone... this is my first thread here.... I'm from Egypt.. and I have a Turkish car called (Tofas - Sahin)
whatever.. this car runs with a fiat engine with the code ( 131CD5 4A)

lots of things are common between this car and the fiat 131...

anyways.. I have a problem with my engine...

The engine can't idle probably no mater what I do.. it keeps giving rich mixture... which results in black fumes in the exhaust of course... and low fuel economy...

I changed the upper fuel injection unit (containing the fuel injector and the fuel regulator) ... I changed the TPS, the lambda sensor, the crank shaft position sensor...
the coils and the spark plugs wires.. the fuel pump... nothing is working out...

it still give rich mix.....

I though it was a problem in my cylinder head.. (as I made grooves in it.. and I also replaced my 1.4 intake valves with the 1.6 intake valves) to gain main power... so I replaced welded the grooves and blasted the head,,, now I only have the 1.6 intake valves with power rings on them... and a ported intake for the cylinder head...

but it still making carbon layers on the spark plugs as long as it's idling..

It keeps idling probably for about 40 seconds.. and then starts to give rich mixture again.... Don't know what to do..
I even changed the ECU.. and still the same problem... The same porting and power rings are made in another engine which is similar to my engine and non of these problems are there.....


any advice???

 

[Hussam]

I tried to reduce the amount of fuel from the fuel regulator next to the injector... and still the same problem... even with the minimum amount of fuel available!!!!!!!!!!!!

Dear lord I'm talking to my self everyday trying to figure out what's the problem!!!

btw I tried to test the Coolant sensor... and it's working perfectly well .. giving the readings mentioned in the data sheet from Magneti Marelli

 

[g8rpi]

Hi Hussam

You are posting in the wrong section. If you are still having problems try posting in "other Fiats" https://www.fiatforum.com/other-fiats/ Sorry I can't help much I don't know your car at all.

Robert G8RPI.

 

[varesecrazy]

Hussam,
is this a new build.. or did the vehicle run OK for a while with these parts..??

 

[Hussam]

Sorry, I forgot to say that my engines car is the same as Tipo engine 1.4 i.e

But it's code is (131F3.016.6409401

 

[Hussam]

No the car was running soo smoothly after the new mods in the cylinder head.

It was idealing perfectly... and the throttle response was incredibly improved.

 

[Hussam]

Please all, I noticed somthing...


the car is idealing badly when the engine is first started and it's still cold. when the engine's coolant reaches a temperature of (50 degrees) the car starts to ideal perfectly.

Then when the coolant's temperature reaches (90) it starts to ideal roughly again.. and throw black carbon fumes from the exhaust.

so it's operating perfectly between (50 and 90)

tried to make sure.. I removed the coolant inlet and outlet hoses from the engine and started running water from an exterior hose connected to an exterior tank with water of an ambient temperature.. for 20 minutes the car was idealing smoothly with no hesitation, vibrations or black carbon fumes and gasoline smell from the exhaust.

After I connected the radiator hoses (engine outlet and inlet) again and started refilling my radiator with distilled water and coolant liquid it was idealing smoothly for 3 minutes and then the problem came back again, the engine started to vibrate and throw amounts of black carbon fumes and gasoline smell....

I tried changing the coolant sensor (located in the intake manifold) with another used one in my friends car... and the same problem was still there in the same operating temperatures....
Any ideas????

 

[varesecrazy]

Please all, I noticed somthing...


I tried changing the coolant sensor (located in the intake manifold) with another used one in my friends car... and the same problem was still there in the same operating temperatures....
Any ideas????

Hi,
it's definitely NOT sensing - or dealing with - temperature correctly,

it's worth checking the engine Timing,
Ignition timing, and valve clearances NOW before going further


IF you just had too much fuel ..it would be good at LOW temp's too.., and it's not:bang:

so test the basic mechanicals 1st,
what grade / heat range of spark plugs..??

 

[Hussam]

Hi,
it's definitely NOT sensing - or dealing with - temperature correctly,

it's worth checking the engine Timing,
Ignition timing, and valve clearances NOW before going further


IF you just had too much fuel ..it would be good at LOW temp's too.., and it's not:bang:

so test the basic mechanicals 1st,
what grade / heat range of spark plugs..??

very organized way of thinking... Thanks for helpin
Yes I already checked the timing of the machine

As for ignition timing I cant as the car is injection and with ignition coils and I cant control the ignition timing... The ECU does

As for the valves clearance
U mean the clearance between the rocker arms and the valve springs?? Or the clearance from inside the combustion chamber???

As for the sparkplugs its NGK with heat range code of 5
Or 6 cant really remember but I'll make sure tomorow and tell u..