Car cranks but no start sometimes

[bayzoo]

Kia Picanto 2009 1L G4HE engine - 45k miles. Car sometimes cranks but doesn’t start, and if it press the accelerator pedal at the same time when starting and I have this issue it does start.

There are no fault codes and it happens if the car is either warm or cold. I’m thinking it could be a fuel delivery issue but it’s done this for a few years (this was my mother in laws car and I’ve I love you rede toy taking ownership).

Any idea where I’d best start trying to fault find?

AI is telling me it could be the IAC valve, MAF, or it even the crankshaft position sensor.

[duncancallum]

Get an obd with live data.

Id be starting with checking crank signal

[E-bmw]

I would start by checking all of the inlet for air leaks if giving it throttle (as in more fuel) means it starts.

Likely candidate could be in the bends of a concertina type air hose.

[bayzoo]

Thanks both - I removed and cleaned the IAC valve and so far so good.

[Doesitdrive]

Put a known perfect battery on it. A very slight drop in voltage can stop a car from starting even if it turns over normally.

Should always be the first port of call with issues like this before paying for diagnostics.

[paul_c123]

Does the rev counter move when you try (does it even have a rev counter??)?

[E-bmw]

Doesitdrive said:

Put a known perfect battery on it. A very slight drop in voltage can stop a car from starting even if it turns over normally.

Should always be the first port of call with issues like this before paying for diagnostics.

I doubt this is the OP's issue as it starts when he presses the accelerator.