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Tzepy
6th November, 2014, 09:38 AM
284817 i have a c-max 1.8l tdci ,the car dosent start when the engine is hot, dosent have any erors,i check the injectors and i chenge the hight presure pomp and fuel rail presure senzor ,temperature senzor but stil have the same problem, live data when engine cranking wht "focom " shows that engine have hot permision to staart do to low presure but on presure section the presure shows right , the problem is only when engine is over 60 degres, when is cold starts perfect

overs0ull
6th November, 2014, 10:22 AM
This is verry strange ussualy this cars don't have problem with hot start ,are you shure all is fine like injector are the keep the pressure , are all sensors are right .
I have one similar problem before time and when the engine go over 70 degreses one or two of the injector (i am not sure how many ) go to make problems ,they start to allow a lot of the fuel from the ruturning lines and the pressure go down and the car start verry hard , but you need to see everything .
Make good diagnostic after 60 degreses when start to make this problems and watch what is happened :
-are the pressure in reil is enought
-are all sensor work correct
-how start to push the fuel in mg
you need to be sure - i that the all components work properly

Tzepy
6th November, 2014, 11:44 AM
I sent the injectors for brahc testing and I check it my self, the hy presure pomp was replace whit a second hand oane but the car that was the pomp started fine the rail presure regulator and rail presure senzor are new,i have no dtc,the car run perfect, the only problem is when is ower 60-70 degres dosent start at al, if the car is started when is cold and the temperature rises to 90 degres car work fine but if I stop the car dosent start again only when the engine cols,whit focom on live data at rail presure shows while crancking betwen 300 and 600 bars but ther is a rubric " presure start permision" and there shows alowed only when the engine is cold..

Tzepy
6th November, 2014, 11:49 AM
I sent the injectors for brahc testing and I check it my self, the hy presure pomp was replace whit a second hand oane but the car that was the pomp started fine the rail presure regulator and rail presure senzor are new,i have no dtc,the car run perfect, the only problem is when is ower 60-70 degres dosent start at al, if the car is started when is cold and the temperature rises to 90 degres car work fine but if I stop the car dosent start again only when the engine cols,whit focom on live data at rail presure shows while crancking betwen 300 and 600 bars but ther is a rubric " presure start permision" and there shows alowed only when the engine is cold..

Tzepy
6th November, 2014, 10:01 PM
anyoane can help me please?

betrescudan
6th November, 2014, 10:53 PM
see temperature sensor

Tzepy
7th November, 2014, 08:48 AM
i have check the temperature senzor and i look at real time value and is working right

overs0ull
7th November, 2014, 06:21 PM
I read all what you read but this is sound extreamly strange : I have two ideas
1-Did you sure in all sensors like Cranckshaft and Camshaft position sensor ,how you say pressure go betwen 300-600 bars that mean :
-have problem with some sensor witch control that like i say up ,i have in the past same problems with JTD fiat when is hot not start when is cold start and after cranckshaft position sensor changing all is fine .
-other thing is tempreture sensor - if he show sh*ts when is warm you will never go to start .
-other thing witch you can check is when is hot and can't start - open the front bonnet , and if you can catch the injectors - make this :
develop the pipes from the rail to injector but from the injectors side (not full develop) just to see are you ahve fuel punch over injectors if you not have the fuel pump have problem or same sensors or rail pressure regulation valvey .
-the last thing witch i can say - put out one injector and leavi it connected to the rail but out of engine on up of the engine , and connected to can oppening , and try to start , if the injector not open and not make atomization out of the engine the conclution is on 1 fuel pump .
Regards