2005 VW Golf Not Starting In Hot Weather

Recently my 2005 VW golf has not been starting in hot weather. The radio, lights, and every other electronic will start when i turn the key. I will push the clutch in and try to start the car and the engine will not even try to turn over. I hear the starter kicking in so I know its not the starter. I had multiple mechanical tests done and no results came up. No warning lights are on. I brought it to a mechanic and he replaced the clutch relay… and that didn’t help. If i leave the car windows open for about an hour after the interior of my car gets too hot the car will start. So I am thinking if it has to do with a relay in the cab of the car. Does anyone know what this will be or what I should try?

First things First we need to know is the car getting spark and fuel into the engine,have you checked all the fuses and the releyes? if that checks out then need to mack sure you our getting spark and fuel and the fuel pressure

i havent checked all the relays. as for the spark and fuel, i’m pretty sure its getting both. The thing is that when i try starting the car the engine wont try to turn over, much like im trying to start the car without pushing the clutch in. I’m thinking it may be a relay under the dashboard that could be affected when the temp of the car interior gets too hot. Although i do not know where to look at for this/these relays.

engine wont try to turn over, much like im trying to start the car without pushing the clutch in.

What do you mean by that? Do you mean that the starter turns but very slowly? Or does it turn normally but it just doesn’t start?

Guys it sounds like it’s not cranking at all. The OP says they hear the starter click, but the way i read it is it’s not turning the motor at all. My first guess would be the clutch safety switch, has the mech tested this?? The click you hear is it a relay from inside the car, or the solenoid on the starter?

The starter clicking but not cranking is usually a sign that the starter motor is not getting enough juice. So I would start with a battery check, battery cables connection cleaning, then starter motor replacement.

I agree. That mechanic replacing the clutch relay (I take it an interlock) kinda implies that is starts normally but he then said that bit about ‘trying to start without pushing the clutch in’.
The two statements are conflicting so that’s why I asked for clarification.

'trying" emoplays the sarter is trying to turn the engine over or crank it. check the clutch switch it could be a hair out of adjustment

yeah i hear the starter kicking in… but the engine itself will not crank over. As for the clutch safety switch the mechanic has not tested it. My car started all day yesterday in 90 degree weather so I’m hoping it was the clutch relay i had replaced. If it still acts up today I will be back on to let you know more about it.

ok so today my car didnt start due to the heat. This is exactly what I heard…
I put my key in and pushed in my clutch. when i turned the key to start it i heard a whine coming from under the dash and the starter clicking… but my engine would not crank over. I tried pulling down on the key to see if i could try moving the ignition around and maybe adjust the wires but that didnt help… once it cooled down outside my car started right up. So I’m pretty sure it has something to do with a relay or something else that is either under the dash or right by my ignition. does anyone know what that could be? (i know this is all kind of redundant but i’m just getting frustrated.)

If you truly hear the starter click, you’re really hearing the solenoid on top of the starter activate.
You do hear the click coming from the starter, right? Make sure because I wouldn’t want to frustrate you even more.

That solenoid on top of the starter’s job is to move a wheel out onto the flywheel and turn 12V onto the actual starter motor.
That part isn’t happening. It has nothing to do with starter switches, interlocks and relays. You are getting power to the starter from the ignition switch, if that click is coming from the vicinity of the starter. All the interlocks and the starter switch are therefore fine. Just because jiggling things around makes it work, does not mean it is the starter switch. It works because the problem happens to be intermittent and possibly is made worse by heat.

Next time it happens where the starter just clicks, get a piece of wood and a hammer.
Put the piece of wood on the starter and whack the other end with the hammer.
See if it will start now. If so, your starter is likely on its way out. They can be fixed, tho.

If that doesn’t help, it could be that you’re not getting enough power to the starter. Check the battery connections, especially the fat one from the starter to the battery.