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Solved ✔ Engine hard to start when is hot - Printable Version

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+---- Thread: Solved ✔ Engine hard to start when is hot (/showthread.php?tid=60508)

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RE: Engine hard to start when is hot - jaki - 11-02-2022

If you force me to give an answer, I guess it is injector leaking.
When engine is toppped, how about rail pressure? Does it stay or drop? I think there is ABL for it.

RE: Engine hard to start when is hot - masa52 - 11-02-2022

OKOLO

Im also  suspecting this flow control valve and maybe will change soon
Fuel filter is new 
Fuel tank dont think so
rail pressure not drop
Car has only 15K miles and I dont suspect Injectors 
This problem happened suddenly 
attaching injector test

https://youtube.com/shorts/01ft0gcGAUE?feature=share

RE: Engine hard to start when is hot - masa52 - 12-02-2022

done some test on cold and hot engine 
maybe this helps find the problem 

Cold Engine start test 


[Image: cold-engine-start-test.jpg][Image: cold-egine-start-test2.jpg][Image: engine-test.jpg]

Cold Rail pressure test

[Image: cold-rail-pressure-test-2.jpg][Image: cold-rail-pressure-test2.jpg][Image: cold-rail-pressure-test.jpg]

Hot Engine start test 

[Image: hot-engine-start-test.jpg] [Image: hot-engine-start-test2.jpg]

Hot rail pressure test 

[Image: hot-rail-pressure-test.jpg] [Image: hot-rail-pressure-test-2.jpg]

RE: Engine hard to start when is hot - Node - 12-02-2022

I don't see any problem in your graphs. In cold graphs start takes about 1.5s from starter on to started. In hot it may be a tiny bit longer, but it still is no more than 1.7s...

RE: Engine hard to start when is hot - masa52 - 12-02-2022

In videos what i attached yesterday you can hear how long car crank till starts
Definitely its something wrong but the question is what??
thanks any way for help!!!

RE: Engine hard to start when is hot - Node - 12-02-2022

Please redo cold graphs. From videos it takes about 0.5s to start on cold, but that is not seen in the graphs. So it's impossible to compare and tell what goes differently.

RE: Engine hard to start when is hot - masa52 - 12-02-2022

Engine and rail pressure test cold 

[Image: cold-engine-start-test.jpg] [Image: cold-rail-pressure-test.jpg]

RE: Engine hard to start when is hot - Node - 24-02-2022

As no one chimes in what I see from this:
1. yes, pressure on hot rises a bit slower than on cold, but IT HAS NO CONNECTION with starting. I mean pressure on hot engine is already higher than on cold much earlier than it starts.
2. the issue I see here is that engine only starts when DDE increases injection quantity from 20 to 30. More or less SAME AS ON COLD.

Have you checked injectors are not clogged and compression is good?

RE: Engine hard to start when is hot - masa52 - 25-02-2022

no i didnt check injectors and compression
car has only 15k and this happened suddenly
I will try to change soon injection quantity valve and will see if this helps
Also have new crankshaft sensor to change
Thank Node for suggestions

RE: Engine hard to start when is hot - davito1 - 25-02-2022

is the starter fast enough?