Lazy starting 95' Legacy ej22

[Bushwick]

Been starting the car daily (undrivable while the rear cross member is getting replaced) and noticing it's been cranking 4-5 sec before starting (just seemed to start doing this oddly). I've got new plugs, wires, fuel filter, and timing belt being shipped and still in transit so none of that has been changed yet. Is there anything else like crank position sensor, ignition coil, fuel pump, etc. that when starting to fail cause slow-to-fire engines? Once it fires it runs fine and revs respond quickly. Thoughts?

[soobie_newbie67]

is it cranking over slow at all? doesn't sound like it but thought I'd ask. if its taking a while of cranking for the engine to fire its typically the crank or cam sensor. the cam sensor was going out on my car. knew it cause it threw a code. sometimes it would start normally, sometimes it would crank for a while before firing up. it finally went out for good, luckily at the junk yard so I just grabbed another one, put it on, and she fired right up and away I went. still works too 15000 miles later

[Bushwick]

^ I'll check the battery after it's been sitting just be sure. The night I bought it and parked it, the dome light had been on all night (PO must have turned it on for some reason while showing me the car as I never touched it). It still started though w/o needing a jump and I let it run for awhile. I pulled the battery to clean it off and paint the battery bracket, replace "J" hook hold downs, etc. and seemingly it started doing this after reinstalling the battery. Connections are OK and clean.

 

 

What's the test procedure for the crank and cam sensors? Any idea what ohms they should display and across which wires? 

[soobie_newbie67]

hopefully someone else will jump on that for ya since I don't know. but if either of them was bad it would throw a code

[WoodsWagon]

Try turning the key to the run position and waiting 3 seconds before turning it to crank. If it fires right up, then your fuel pressure is bleeding down. That can either be the check valve in the pump or the fuel pressure regulator. If it is this, then it's not really a problem really, just pause in run before cranking it to let the fuel pump prime the system.

 

The other thing I'd think of is the coolant temp sensor for the computer. If that's starting to fail it can give the computer a bad reading as to how cold the engine is and it won't feed in the extra fuel needed to get it to fire off. It's like the choke on a carb engine. There's two sensors, one for the gauge, one for the computer, so keep that in mind if you replace it. It's easy to check with an obd2  scan tool, just go into the live sensor readings and check if the coolant temp reading matches the outside temp if the engine has been sitting cold. Then start it and see if the temp reading climbs up to 195ish when the gauge hits the middle of it's range.

 

Since it started after you messed with the battery, I would also suspect the cables. If they are corroded internally, bending them as you pull off the connections could have cracked the wires inside. But that would cause slow cranking.

 

With the battery disconnected, the ECU also resets. So it may need to re-learn the idle but it should have done that the first time you started it up and let it run for a while.

Edited October 16, 2013 by WoodsWagon

[Bushwick]

Thanks for the advice WW. Been focused on getting the rear back together before I tackle the stuff under the hood, so haven't had a chance to investigate further. Good point about a coolant temp sensor. Will investigate further once the fuel filter and extra parts arrive sometime in the next couple days and hopefully update with good news.