12 replies to this topic

[Grey]

Hi, I'm Grey, new to the club. I live in Northern Minnesota and have a problem with my 97 Imprezza in cold weather (below 0). The car starts fine 1st thing in the morning. If I drive it only a short distance, 5 minutes or less in the city, turn it off, and try to restart after 5 to 20 minutes, it often almost starts (catches but immediately dies) and then refuses to start (turns over but won't catch) unless I let it sit for 20 to 30 minutes, at which time it starts fine again. If I drive it long enough for the engine to warm up I don't have the problem. Neither the dealer or SOA have a clue. I left it at the dealer one cold night so they could experience the problem the next morning but it wouldn't act up for them. Any help will be greatly appreciated; this is a very annoying problem that has been happening for years.

[Downbound]

sounds like it could be something as simple as gas line freeze up...do you keep the tank topped up in the winter? do you have a block heater? do you add gas line antifreeze at all? We get very simialr weather here in eastern ontario It is -25 c right now with a wind chill of -37C and have learned through experience that if you let the tank run low and then sart up on a cold day run a short distnace then turn it off you can end up with a frozen gas line pretty quick..might seem too simple but sometimes we look for complicated solutions to simple problems..good luck

[cookie]

They are very cheap and easy to replace to find out. It might be working well cold or hot but not in medium ranges.

[Grey]

sounds like it could be something as simple as gas line freeze up...do you keep the tank topped up in the winter? do you have a block heater? do you add gas line antifreeze at all? We get very simialr weather here in eastern ontario It is -25 c right now with a wind chill of -37C and have learned through experience that if you let the tank run low and then sart up on a cold day run a short distnace then turn it off you can end up with a frozen gas line pretty quick..might seem too simple but sometimes we look for complicated solutions to simple problems..good luck

Thanks for the answer. Don't know how full or empty the tank has been, or if there is a relationship. If the problem is fuel line freezeup, why would waiting 20 minutes matter?

[Inday]

Does it only do it in cold weather?
I have got the same problem but independently by temperature. I posted it here somewhere a fortnight ago. When it happens, I just wait 15 to 20 minutes, then it starts again. I had it at the dealer's and it did not throw a code when it did not want to start anymore. After some testing the car started again and testing could not be proceeded. Really annoying. @Nug mentioned it might be the ECU.

[Grey]

Yes, only in cold weather.

[cookie]

than an ECU. If an ECU gets the wrong input it is going to do the wrong thing.These are known to be a failure point. You could always move to Florida.

[mtsmiths]

than an ECU. If an ECU gets the wrong input it is going to do the wrong thing.These are known to be a failure point. You could always move to Florida.

Jeeze Cookie, moving to Florida is cheaper than an ECU!

[cookie]

I noticed this guy about my age that was rpobably retired there. His job was to look at the waterway and raise the bridge if a sailboat or one of those sportfishermen with a tuna tower came by. Now I could handle that.
I wouldn't be too worried about cold start capability there either.

[Nug]

You need to check several things during the time it won't start. Does it have spark? Does it have fuel? I seemed to recall it having spark, but possibly no fuel being injected. Is this correct?

You need a systematic approach.

[Nug]

Ok, I'm mixed up.


Anyway, if it takes 15-20 minutes to restart the car, then that should give you plenty of time to figure out where the problem is coming from.

1. Do what you need to do for the symptoms to show themselves. Run car and shut off, etc.

2. Check for spark. If it has spark, move on to fuel system.
2a. No spark? Then it is crank or cam sensor, coil, ignitor, wiring, or ecu. Check for a voltage pulsation from cam and crank sensor while turning the engine over, check for 12v at coil, check for voltage at both outputs of ignitor.
Check for power at ecu.

3.Got spark? Then check fuel system.
3a. Do you have fuel pressure? Does the pump turn on when you turn on the key?
3b. Do the injectors fire while cranking? verify with a noid light.

If you run into some really weird isht like spark, but no injector output at all from ecu (checked directly at ecu) then I might suspect ecu. Some other sensors will cause a no-start, like MAF, possibly. Things like that need to be verified using the FSM. (I.E. if the ecu doesn't see the MAF, it may keep the injectors from firing. I don't know, but my factory service manual does).

Get a copy of the FSM, it has flowcharts of exactly what to check, step by step. Basically, a volt/ohm meter is the only tool really needed.

[Grey]

Ok, I'm mixed up.


Anyway, if it takes 15-20 minutes to restart the car, then that should give you plenty of time to figure out where the problem is coming from.

1. Do what you need to do for the symptoms to show themselves. Run car and shut off, etc.

2. Check for spark. If it has spark, move on to fuel system.
2a. No spark? Then it is crank or cam sensor, coil, ignitor, wiring, or ecu. Check for a voltage pulsation from cam and crank sensor while turning the engine over, check for 12v at coil, check for voltage at both outputs of ignitor.
Check for power at ecu.

3.Got spark? Then check fuel system.
3a. Do you have fuel pressure? Does the pump turn on when you turn on the key?
3b. Do the injectors fire while cranking? verify with a noid light.

If you run into some really weird isht like spark, but no injector output at all from ecu (checked directly at ecu) then I might suspect ecu. Some other sensors will cause a no-start, like MAF, possibly. Things like that need to be verified using the FSM. (I.E. if the ecu doesn't see the MAF, it may keep the injectors from firing. I don't know, but my factory service manual does).

Get a copy of the FSM, it has flowcharts of exactly what to check, step by step. Basically, a volt/ohm meter is the only tool really needed.

Grey. Thanks for the information. This is beyond my abilities as a mechanic (basicly none) and besides, poking around inside the hood of a car, outside at 20 below isn't much fun. I appreciate your help, though.

[Grey]

Thanks for the information. This is beyond my minimal mechanical abilities and besides, poking around inside the hood of a car, outside at 20 below isn't much fun. I appreciate the help, though.