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Hello USMB,

 

I have a 2005 Forester with 172k miles on it in Boston. In October (3 months ago), I was having some issues with the engine stalling when it was rainy out. I could get the car driving, but once I would get up to ~2500 rpm in the rain, the engine would sputter and lose a lot of power. 

 

To fix this problem, I changed out the ignition coil and the wires to the spark plugs. I used Duralast parts for this. This seemed to fix that problem, but a new problem arose.

 

Since swapping the coil and wires, the car will oftentimes not start. It will crank and crank, but will not start running on its own. In cold weather (less than 20 degrees F), there is not really much of a chance it will start. In warm weather, it will start sometimes. Hooking up jumper cables to another car would help sometimes, but not always.

 

I have since replaced the spark plugs and cam position sensor (1 of 2?), which didn't help at all.

 

I had the car towed over to a mechanic who tried diagnosing it for the last two weeks. He discovered that when the issue was happening, there was no spark. However, he could not figure out what the issue was. He replaced the crankshaft sensor, but that did not help either.

 

In week 2 (last week) of the car being in the shop, the car was starting up every time. I picked it up and drove it home with no problems since I need the car for work. Ever since then (2 days ago), I am having the same issue again and have not been able to get it to start a single time.

 

At this point, I am thinking perhaps it is the wiring or the connector to the ignition coil, the ECU, or perhaps another sensor. Before I try poking around in there some more, I am hoping someone here might have some advice on this case.

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Can you hear the main relay clickwhen you turn the key to on? You should hear two clicks.

The main relay supplies power to the ecu so that would be a good place to start since you checked the cam sensor already.

I don't know if 2005 has an igniter before the coil, but that can fail too - although that is rare.

Check your ignition system to be sure you are getting 12 v where you are supposed to with the key on and during cranking as well, it could just be the ignition switch. Have you tried going from off straight to start or trying several very short bursts on the starter?

 

you may have to find a wiring diagram or a pinout for your ecu.

Edited by sparkyboy

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Subies prefer OEM coils and NGK wires (not Durac*ap parts).

 

If its having trouble starting in cold weather it could be your coolant temp sensor since that adds fuel when its a cold start

 

Could also be a slipped timing belt (was your timing belt service done at 105k miles?)

 

That's just my uneducated opinion.

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both the manual and auto have some neutral safety type wiring. Try starting in Neutral 'popping' the brake pedal once or twice if auto, if 5 spd,  try 'popping' the clutch pedal.

 

 

older denso starters do often need new contacts in the solenoid - kits are available for that.

 

if it's cranking but not starting, maybe aftermarket parts or maybe oil on the plug boots ???

Edited by 1 Lucky Texan

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I hopped in this morning to see if I could get it running. Still no start. I listened for the two clicks from the main relay and could hear it every time.

 

I am going to try probing the ignition coil pack when I get home from work tonight to see if I am getting 12v where/when it belongs and will post results. I want to see if the Duralast coil is giving me the  issues or if it somewhere before there. I still have the original pack handy so I can try it out, but I will need to drill out one of the connectors as the old plug connector is jammed in there.

 

So far, I have tried all manners of starting: straight on, short bursts, stepping on pedal a bit to let air in, stepping on brake to jog safety mechanisms. I will try jiggling around the shifter (auto), but I have found that this failure typically prevents the engine from cranking in the first place, so I don't think this is it.

 

Not sure if the timing belt (and other applicable service) was performed at 105k miles as I bought the car at 162k miles, so perhaps this could be it.

 

@bstone, your issue sounds a lot like mine! Does anyone know if 05 Foresters have a separate igniter from the coil pack? Having trouble finding any references to this online.

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2 things if not successful - try HOLDING the pedal to the floor. That signals a 'clear flood' routine and the ECU will hold-back fuel in case the car is flooded. This can crop-up with folks who drive a cold car a short distance, turn it off to close a gate or garage door, then try to restart - uncommon but.....?

 

on the other side, you could try some spraying some starting fluid in to see if it's fuel starved.

 

might be worth scanning for pending codes.

Edited by 1 Lucky Texan

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Chaid--are you sure the two clicks are coming from the main relay?  Or could it be from the starter solenoid?

 

If it was the solenoid clicking, that could mean burnt/pitted copper contacts.  Easy fix.

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I

@bstone, your issue sounds a lot like mine! Does anyone know if 05 Foresters have a separate igniter from the coil pack? Having trouble finding any references to this online.

Hard to say. Have you tried putting your particulars in a few auto parts websites and seeing if an igniter is an option? It's also called an "Ignition Control Module". I'm also in Boston and I think this extreme cold is killing our electrical systems.

Edited by bstone

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Solved! Almost.

 

This evening I tried probing the ignition coil input wires for voltage with a multimeter. I first removed the Duralast igntion coil (the culprit). I turned on the car to the on position (not running), and the voltage was 24 volts from one of the pins to ground. I was surprised that it wasn't 12 volts, but it had voltage at a common value, so close enough. Two other pins were at 0 volts with the engine off, but flickered between 0 and ~24(?) volts when cranking: the expected response. On the '05 Forester there is a 4th pin on the ignition coil pack, which I believe is signal for the built-in igniter control module.

 

I also checked the resistance across the OEM coil pack and the Duralast coil pack. Around 11.3 k-ohms for each loop on the OEM and 10.5 k-ohms on the Duralast pack. In the service manual, the spec is 12.8 k-ohm +/- 15%, so this resistance really shouldn't be below ~10.9 k-ohms.

 

I put in the original OEM coil pack. It now starts every time! However, the first time I started it up it was shaking around a bit as if one of the cylinders isn't firing correctly. I somewhat expected this because the old plug contact was ripped off and lodged in the OEM coil pack socket and I had to drill it out to fit in the new plug. After shoving the plug in a bit more and driving around a bit it wasn't so shaky anymore. However, I now have a steady check engine light and the green cruise control light is slowly flashing.

 

I am going to go have the error read since I don't have a reader and will report back with the code and the fix once I know more. I am anticipating that I will need to get a new OEM coil pack most likely. Also, we will see if the initial stalling problem returns or if the replacement wires fixed that. Fingers crossed. Will need to wait for rain for that to happen, perhaps this Wednesday it should be warm enough for rain here.

 

Don't use Duralast ignition coil packs for Forester! OEM only!

  • Like 1

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Solved! Almost.

 

This evening I tried probing the ignition coil input wires for voltage with a multimeter. I first removed the Duralast igntion coil (the culprit). I turned on the car to the on position (not running), and the voltage was 24 volts from one of the pins to ground. I was surprised that it wasn't 12 volts, but it had voltage at a common value, so close enough. Two other pins were at 0 volts with the engine off, but flickered between 0 and ~24(?) volts when cranking: the expected response. On the '05 Forester there is a 4th pin on the ignition coil pack, which I believe is signal for the built-in igniter control module.

 

I also checked the resistance across the OEM coil pack and the Duralast coil pack. Around 11.3 k-ohms for each loop on the OEM and 10.5 k-ohms on the Duralast pack. In the service manual, the spec is 12.8 k-ohm +/- 15%, so this resistance really shouldn't be below ~10.9 k-ohms.

 

I put in the original OEM coil pack. It now starts every time! However, the first time I started it up it was shaking around a bit as if one of the cylinders isn't firing correctly. I somewhat expected this because the old plug contact was ripped off and lodged in the OEM coil pack socket and I had to drill it out to fit in the new plug. After shoving the plug in a bit more and driving around a bit it wasn't so shaky anymore. However, I now have a steady check engine light and the green cruise control light is slowly flashing.

 

I am going to go have the error read since I don't have a reader and will report back with the code and the fix once I know more. I am anticipating that I will need to get a new OEM coil pack most likely. Also, we will see if the initial stalling problem returns or if the replacement wires fixed that. Fingers crossed. Will need to wait for rain for that to happen, perhaps this Wednesday it should be warm enough for rain here.

 

Don't use Duralast ignition coil packs for Forester! OEM only!

Excellent work! Our vehicles are so sensitive to parts and it almost makes sense to always buy OEM just to you don’t go through an epic saga like you have. When you scanned the code for the current CEL what did it say? I might clear the codes and wait until the CEL comes back on (if it does) in order to get a more accurate view of the current troubles.

 

Have you tried reticulating the splines?

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24v seems a bit excessive!

 

Hope this is not repeating stuff everyone knows by heart...if so, Sorry!

 

4 wire coils, (IIRC, have the transistor built in the coil pack) have a common 12v feed, a controlled ground for each coil and a timing signal from the ECU.

 

If only 3 wire coil pack it will have an igniter to control it.

 

4 wire COPs have a 12v supply, transistor controlled ground, a transistor base control from ECU and a ign conformation to the ECU.

 

3 wire COPs is same except for the ign conformation.

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Glad to hear that it was an easy fix.

+1 on not buying cheap spark plug wires, I bought a cheap set for my Camaro when she had a bad misfire, along with new plugs. She ran so s**ty that I was about to pull the valve cover off. Three of the wires were no good. The misfire turned out to be condensation under the rotor cap and the old wires (that have been on the car since I can remember) were just fine. Whoever made those made a good set because they have been on the car for 22 years. They have never needed replacing.

The cheap spark plug wires are useless.

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