My car will start when it’s cold, but won’t start when it...

do I text here or what?

Thanks for using JustAnswer.com! My name is \*\*\*\*\* \*\*\*\*\* I'll try to answer your car questions. I'll start off with some basic checks to do, then we can get into more advanced diagnostics if needed. Let me know if any questions come up, or if there is anything I can do to help! You can update this message at anytime. - I'm sorry to hear about any troubles with the vehicle, but would be glad to try and help! - Usually this is a fuel system related issue, but have seen the crank sensors act up at times. Youll notice no RPM reading on the tach or scan tool when cranking the engine over. Are there any trouble codes setting? Has fuel pressure been checked when the engine isn't starting? - Lemme know what youre seeing, or if any questions come up while checking things out!

The o2 sensor was on, I replaced that we changed fuel pump, high pressure pump, and fuel pump sensor on the fuel rail. Yes I checked fuel pressure

Ok sounds good, if fuel pressure is normal when cranking it over, are you missing spark or fuel injector pulse? Are you seeing any trouble codes setting in any of the modules?

On the scanner it's showing we have pulse on the 1st pulse but not the second pulse. it does have spark Not sure if this is what u mean but the scanner is reading no codes presentDon't know if this will help but the car won't start if the temperature is at 137-147

Ok, if youre seeing spark, suspect that the crank sensor signal is being seen. Look for RPM signal on the tach or scan tool to verify this. Check for fuel injector pulse using a noid light tester. If youre seeing good spark and fuel injector pulse while cranking, as well as good fuel pressure, recommend checking engine compression and timing. If not seeing fuel injector pulse, let's look into the signal from the camshaft sensor at that time. Lemme know what youre seeing, or if any questions come up while checking things out!

What would considered good signal ?

Pardon?

My scanners not showing rpm signal

Ok gotcha, I'm suspecting that the RPM signal from the crankshaft position sensor is being seen, if you have spark while cranking the engine over. We'll want to move now to see if the fuel injectors are getting the signal to fire from the engine computer. Use a noid light tester or a test light at the injector connector. If not getting a signal we'll look at the input from the camshaft position sensor, but would suspect some codes setting for this sensor. Might try resetting the computer by disconnecting both battery cables and touching the cable ends together for 2 minutes. If you are getting a signal to the fuel injectors, let's check compression and engine timing at that time. Lemme know what ya find, or if any questions come up!

Just checked and it has good spark, good fuel injector pulse and good fuel pressure, fuel injector is telling it to fire and I reset the battery and still no codes. Ran a compression test and compression is at 150

Sounds like it should be starting then. How much fuel pressure are you seeing on the gauge, and how much pressure is the fuel rail pressure sensor reading? Is the engine starting right now, or no? Does the engine keep running past the 137-147 degree mark, but then not start afterwards, or does it stall once it reaches this temperature?

From the tank seeing 60psi, it starts at every temperature except from 137-147 I'm only seeing issues at those temperaturesRuns and drives fine, the issue is if I turn it off at the 137-147 temperature it won't turn back on until it cools down

If the engine is warmer, like 180-200 degrees, is there any problem re-starting the engine? Which engine is in your vehicle?

Just tried it, it does re start at 180-200Engine is 2.4

Does engine restart as soon as it reaches 136 degrees or 148?

No

Are you ever seeing the fuel pressure come up into normal ranges? Specification is 69-75 psi. Does the fuel pressure drop off rapidly when the engine is shut off, or does it stay constant at all times?

It stays consistent, haven't seen it as high as 70

If you were to disconnect the engine temp sensor, would the engine start right away? It sounds like either the computer is missing an input when the engine reaches a certain temperature, or it's unable to control the ignition and fuel systems correctly, and will need to be replaced, but would recommend having it updated to latest level software and rechecking operation, as well as double checking power and ground supply circuits to the computer before replacement.

When I disconnect, the temp sensor the car won't start. So it's most likely an issue with the computer?

With scan tool, see if commanding the fuel pressure valve/regulator closed so that highest fuel pressure is made. If still seeing 60 psi, inspect fuel system and lines/filter for restrictions, or the fuel pump power supply. See if running direct power to the fuel pump brings pressure up into normal ranges, double check ground connection as well. If all inputs are correct, and youre seeing fuel and spark while cranking, but engine isn't starting, suspecting a computer issue is occurring and it isn't timing the engine correctly. Also check to see that the missing engine temp sensor input is being seen on the scan tool while sensor is unplugged. If it's still reading 137-147 degrees, look for shorted wiring to the sensor. Try holding gas pedal to the floor to clear flood mode and see if engine will start with sensor connected and disconnected and see if any change. If engine still isn't starting, but fuel injector pulse and spark are present, as well as good fuel pressure and compression, suspect engine computer issue.

Fuel pressure regulator is off and the scanner is reading the high pump at 606The shop I'm at is closing up I'll try the rest of the diagnostic tomorrow

Ok sounds good, lemme know how it goes tomorrow, I'm sure we can get it figured out, but if engine isn't even trying to start with 60 psi when at those temps, suspecting that the engine computer isn't sending proper ignition timing or fuel injector timing signals. Might try warming and cooling the engine computer with heat gun and ice and see if any change in operation, or if the spark or fuel injector signals drop out at times while trying to start it. If still not starting, but youre seeing all inputs and fuel/ignition system control, would replace the engine computer and retest.

Loved “Ok sounds good, lemme know how it goes tomorrow, I'm sure we can get it figured out, but if engine isn't even trying to start with 60 psi when at those temps, suspecting that the engine computer isn't sending proper ignition timing or fuel injector timing signals. Might try warming and cooling the engine computer with heat gun and ice and see if any change in operation, or if the spark or fuel injector signals drop out at times while trying to start it. If still not starting, but youre seeing all inputs and fuel/ignition system control, would replace the engine computer and retest.”

Hello! Hoping that helps figure out what's going on with the car, lemme know how it goes, or if any questions come up while checking things out! Thanks again for using JustAnswer.com!

Was up Marc good afternoon, been doing some tests and I can't seem to get it past 60 psi, engine temp sensors being seen. Wiring is good and when I try to turn it on while flooding it, it won't turn on

Even with just 60 psi, it should be trying to fire I would think. Are you seeing good spark and fuel injector pulse at each cylinder while cranking engine over? Do you see the fuel trims change, or oxygen sensor data change from normal, when it's not starting?

Everything looks good, I think I'm gonna try and flash the computer

You bet, sounds like a plan. If still acting up at that point, would replace the computer and retest. Lemme know how it goes!

Hey Marc, so I was doing a little more investigation and the car sounds like a lifters giving out. Could the lifter be the issue?

Sorry for delay. Lifter could be a problem, but would think you would see low compression on one of the cylinders. We better get it back to the point that it wont start again, then would run a cylinder leakdown test and see if youre losing compression on any of the cylinders. If not seeing any compression loss, we can rule out the lifters. Lemme know how it goes, or if any questions come up!