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In fuel-injected systems, hot-start problems indicate that the fuel line is unable to maintain pressure. This could be due to a few things related to the fuel supply line, including: a leaky fuel injector minute cracks in the fuel line which leak fuel when under pressure a bad non-return valve in the fuel line which is allowing pressurized fuel to flow ...


5

The usual idea is that with 2 wires; one is ignition controlled 12v and goes to the resistor (block on the side with two terminals) so that the coil receives about 9v during normal running. The other wire is 12v when the starter is operated and is used to feed the coil with 12v so it gets a higher supply voltage during starting - to offset the voltage drop ...


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It sounds like the car is unable to maintain sufficient pressure in the fuel rail. Have a look at this answer for more details on potential causes for hot start problems. The reason why this happens only for hot starts is because the fuel is more likely to vaporize as temperature increases. In order to avoid vaporization problems the fuel lines are ...


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In fuel-injected systems, hot-start problems indicate that the fuel line is unable to maintain pressure. This could be due to a few things related to the fuel supply line, including: a leaky fuel injector minute cracks in the fuel line which leak fuel when under pressure a bad non-return valve in the fuel line which is allowing pressurized fuel to flow ...


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It sounds like the car is unable to maintain sufficient pressure in the fuel rail. Have a look at this answer for more details on potential causes for hot start problems. It is usually a good strategy to confirm suspicions through measurements and/or diagnostic tests, many of which can actually be performed by an average DIY-er. As you saw with the MAP ...


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Probably an engine temperature sensor. I had a similar issue with a '89 VW Fox. Cold temp would start fine and the moment it got warm.....died. Wait 10 minutes good to go until it got warm. Good thing I had a service manual in the car and a calculator. I was near a Radio Shack and picked up 2 thermistors put them together plugged them in and tie wrapped ...


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Pull all your spark plugs, careful not to mix them up in reference to which cylinder they were IN. Are ALL of them as BAD as That one you show us here? IF that plug is the darkest, IS IT FROM THE CYLINDER that your FUEL PRESSURE REGULATOR gets its vacuum suction from on the INTAKE RUNNER feeding that dark over fueled spark plug. HINT undo the vacuum hose ...


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Fuel Rail Pressure was around 6 bar when off (25 bar when on, 70+ bar at WOT), it remained this even after 2 hours (I'm guessing it primes when you turn on the ignition) I believe this is the root of your problem. The fuel rail needs to maintain a certain pressure so that the vehicle can start up with the engine hot. If the pressure isn't high enough, the ...


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tnx for all the help. I finally have found the issue to my problem. it turns out that the coil boots were melting onto the plugs. I replaced all the plugs and coil boots. also it turns out I had a bad cam shaft sensor. once those 3 things were replaced the issue never came back. lets not jinx it now. but yeh, no issues


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Ticking the boxes of ignition and basic maintenance I'd be looking at your fuel injectors. The pintles can wear out and allow fuel to bleed off into the cylinder thus dropping pressure. This excess fuel in the cylinder can cause a flooding condition on warm start which the PCM doesn't know how to deal with since it expects fuel pressure to be there and thus ...


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My diesel runs the glow plugs for about 10 seconds, and I usually hit the starter at about 7 secs. They do go off after the light goes out, so cranking the starter after that tends to just flatten the battery. So it is better to re-cycle the glow plugs - a question of understanding the vehicle.


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I've seen this type of behaviour caused by fuel vaporisation. This is where fuel system components or supply lines are routed close to hot components and not adequately shielded. This can cause fuel to effectively boil in the fuel lines so when you attempt to start the vehicle, it is massively lean until the point where cool fuel pumped up from the tank ...


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Yollooool's answer is excellent and sounds like a very real possibility given the history you describe. Another thing that could potentially cause problems starting when the engine is warm is the coolant temperature sensor - I had very similar symptoms when mine failed.


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Whoohpppphhhffhh, that's a loooong array of problems you've suffered; Better you than me! :P You have said the engine overheated at one point. This can be a cause of the hard starting when warm. It can also be down to the engine heating up the injectors. It doesn't stop it from starting altogether, but it can cause difficulty in some cases. In theory, the ...


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The rpm sensor was a good candidate. I would consider the following tests: Start it warm with opened fuel filler flap. Clean the contacts of every temperature sensor and the crankshaft position sensor (Plugging them out and in several times). Does the exhaust fume smells like petrol? (Attention: Health hazard!). Spray start-pilot while starting the ...


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There is not enough information as others have indicated, however, the most likely cause is that the vehicle has a bad sensor that is telling the computer that the engine is warm when it is not so it doesn't enrich the mixture sufficiently. No choke is used on these cars. If the car is real old '70s or before, the mechanical choke would cause this type of ...


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My best guess would be the crank angle sensor, the cars ECU (computer) relies on the crank angle sensor to fire the injectors and spark plugs, if the crank angle sensor is not working correctly you will get all kinds of problems including what you have mentioned.


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NGK is backwards with heat range, meaning the lower the numeric digit is, the hotter the NGK plug is. This is unlike every other spark plug where you get colder in heat range when the number is lower. So if you seek a band aid till you figure the problem out.. place a hotter plug in just the holes that show carbon deposits on the plugs, so it won't foul ...


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First of all, connecting negative and positive connections with a butter knife is called a short circuit. I am surprised that you didn't burn a fuse, start a fire or explode the battery yet. DO NOT SHORT CIRCUIT TERMINALS WITH BUTTER KNIFE! IT IS DANGEROUS (and I don't actually understand why you think it would help?) The reason for the knife to get hot is ...


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More than likely you have injector(s) leaking down when hot. If not that it can be a fuel pump or fuel pump pressure control, newer diesels can be complicated to diagnose here due to computer controls.


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