BACKYARD MECHANIC: Saturn Ion giving owner the cold shoulder

Hey there, time traveller!
This article was published 03/02/2012 (5312 days ago), so information in it may no longer be current.

QUESTION: I have a 2005 Saturn Ion with about 95,000 km, which I purchased in January 2010. On cold mornings — basically on cold mornings after damp nights — when I turn the key in the ignition first thing in the morning, all the lights and the fan will come on, but the engine will not actually start. If I wait an hour or two it will start fine. I replaced the battery. This would not solve the problem. I had the alternator tested twice; it was functioning properly.

As the season got warmer last year, the problem solved itself, though this winter it is doing the same thing again. The garage told me the starter was freezing up. I replaced the whole starter though this did not solve the problem either. What may be the problem, and what should I advise them to try next? Could it be an issue with the sensors or electrical system? I think possibly though my mechanic says no. David

ANSWER: The battery and starter have already been replaced, and a faulty charging system would not prevent the vehicle from starting if the battery still had a charge. I agree with you that the fault is with the electrical system.

There are three things I would check initially. First, look under the dash and see if there is some non-factory wiring installed that could be for an aftermarket remote start system. I have seen several of these modules fail intermittently in cold weather and they could be preventing the vehicle from starting.

Next, I would look for the security light being illuminated on the dash. If the security light is on, this would indicate there is a problem with the passlock system. The vehicle recognizes the electronic signal from the ignition key and if the signal isn’t there, on many vehicles including your Saturn, it won’t start. If the security light is out, then it shouldn’t be the passlock system that is preventing the engine from cranking.

The third item to check, and a more common problem on these vehicles, is a faulty ignition switch. When the switch is cold, some contacts in the switch don’t make a good contact and the vehicle doesn’t crank. Let it warm up a little and it will begin making contact again.

Sometimes a faulty ignition switch will set trouble codes in the body computer. This is because the switch wiring goes to the body computer, which then communicates with the engine computer and the engine computer cranks the starter by commanding a starter relay.

If you had a scan tool in the vehicle, you would be able to see if the switch signals were getting to the body computer. If not, replace the ignition switch. If they are, then you need to look at wiring connections and possibly the starting relay in the fuse box.

QUESTION: I have a 2000 Volvo V70 XC with the five-cylinder turbo engine and ever since the weather has turned extremely cold, it has been getting gradually worse fuel economy and down on power.

I changed the spark plugs and added fuel injector cleaner to the fuel tank but it is still getting worse. It starts and idles fine and will even drive at low speeds smoothly, but try to accelerate quickly or drive on the highway and it just doesn’t want to go. The same thing happened last winter but it was OK in the spring. Any suggestions would be appreciated. Graham

ANSWER: I may have a simple solution for your problem. The exhaust system is likely plugged with ice. The mufflers are at the very rear of your car and moisture from the exhaust can build up in the mufflers and freeze solid in very cold weather, blocking the exhaust flow. If you do mainly short-trip city driving, this problem is more likely.

Park the car in a heated building for a day (underground shopping centres work) and then take it out for a drive to blow the moisture out the tailpipe. Drill a small 1/8th-inch hole in the bottom back end of each muffler as a drain hole and the problem shouldn’t happen again.

Jim Kerr is an experienced mechanic, instructor and member of the Automobile Journalists’ Association of Canada.