Automotive question for mechanics out there

[CLT65]

I have a question for all of you who are mechanically inclined. We have this car, an old PT Cruiser, that has a strange problem. it's really not worth spending much money on for parts or a mechanic.

It will start and run fine, for about 5 minutes until it warms up. Then it sputters and dies, and won't start again until it's completely cooled down.

It actually doesn't belong to me. Friends of ours are going to give it to my daughter if we can get it running right. I'm thinking a fuel problem, he thinks electrical. Any ideas for where to start troubleshooting?

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[Asavage270]

I have no experience with PT cruisers but have wrenched on a bunch of my own vehicles over the years.
XJ jeeps get a similar problem known as "vapor lock"

Essentially the fuel in your fuel lines near the engine (before it gets sprayed through your injectors into the combustion chamber) gets heated by the ambient engine temperature.
Resulting in vaporized fuel inside the fuel lines, this causes the same symptoms your describing.
Its a cheap fix also, all you do is insulate the fuel lines with a high heat rated insulation which keeps the fuel cool until it gets used by your engine.

 

[slimmer13]

I had an F150 that had a similar problem. It was the Fuel pump control module, a little computer mounted on the frame rails. No idea if those have a similar system.

 

[Asavage270]

Other common / cheaper issues I would look into would be replacing the O2 sensors, and replacing the ignition coil. Sometimes when hot/ damaged / old the coils will not work properly.

 

[titsonritz]

I had a similar issue, it turned out to be a bad inline solenoid.

 

[CLT65]

Thanks guys, I appreciate it. That definitely gives us somewhere to start!

 

[Member 34319]

I'd say injector issues. What's the mileage? Assuming proper typical maintenance like oil and such is taking place?

 

[Mikej]

Could be 100 things! Completely dead after partial warm-up could easily be an ignition part having a break because of the heat. We ha ve an auto tech here. Can't think of his handle now.

 

[Hop Sing]

Could be 100 things! Completely dead after partial warm-up could easily be an ignition part having a break because of the heat. We ha ve an auto tech here. Can't think of his handle now.

While not hip to PT Cruisers, I'm inclined to go along with a heat issue affecting the ignition system.

 

[CLT65]

I'd say injector issues. What's the mileage? Assuming proper typical maintenance like oil and such is taking place?

Around 100k. I don't know about maintenance, but the owner is a pretty particular sort so I assume routine maintenance has been pretty good.

I'm thinking he's already done some research, because he mentioned at the start that he thought it might be a faulty ignition component. It might be a couple weeks before we get around to it, but I'll let you all know what we find, assuming we fix it.

Thanks everyone!

 

[Certaindeaf]

Disconnect the battery and then reconnect. If that doesn't work, chicken bones and a magic wand.. or a 30-06. same thing, really
That or the voltage regulator.

 

[bionic knees]

possible camshaft position sensor, they are kind of known for failing, often just like you described.

 

[CLT65]

Coming back around to an old thread- we never did get this going. Finding time to get together and work on it has been challenging, for a number of reasons.

Here's what we've done. We replaced the ignition coil, wires, and spark plugs. The plugs were unbelievably bad, burned to stubs. I also bought a new battery. It started, ran great for maybe ten minutes, then died and wouldn't start again. After I left and it cooled down, he said it started right up. This was a couple months ago. No engine codes.

I bought new camshaft and crankshaft sensors, and finally made it out there again today. It started right up and he drove it into the shop. I replaced the crankshaft sensor, and it started up and ran great for maybe ten minutes, then, same as before, it died just like flipping a switch. This time it wouldn't even turn over to try to start. The battery is good, but electricity isn't making it to the starter. The dash lights up, but it doesn't even try when you turn the key.

At this point it sure seems like an electronic problem, since a fuel issue wouldn't cut juice to the starter. We could take it to a mechanic, but I'd hate to throw good money after bad.

 

[Ferryman]

You c

I have a question for all of you who are mechanically inclined. We have this car, an old PT Cruiser, that has a strange problem. it's really not worth spending much money on for parts or a mechanic.

It will start and run fine, for about 5 minutes until it warms up. Then it sputters and dies, and won't start again until it's completely cooled down.

It actually doesn't belong to me. Friends of ours are going to give it to my daughter if we can get it running right. I'm thinking a fuel problem, he thinks electrical. Any ideas for where to start troubleshooting?

You could have a problem in your exhaust system. Someone already stated to check your O2 sensor, I would also inspect your catalytic convertor and the rest of your pipes.

 

[CLT65]

It's hard to imagine how anything fuel or exhaust related would cause it to run just fine, then shut off like flipping a switch, and not even try to restart. We've come to the conclusion that it must be electronic. We're wondering about the computer.

 

[cd90caprice]

Without being there I won't be much help. It does sound like it could be a PCM issue. You can try tapping on it with the handle of a screwdriver while it is running good, if it stalls you have most likely found the culprit. You dont have to beat it like it owes you money, just some good solid taps. Having replaced the cam and crank sensors already one of the only other things I can think of is making sure the gray security key is being used, although if it wasn't it shouldn't run for more than a few seconds anyway.