After searching HAF for a while now I haven't found the "silver bullet" to my problem!

Occasionally when starting, the engine will crank over very slow, fire once, crank another couple revolutions and then start with a little stumble for the first few successful firing strokes on the way getting to idle. Then it runs smooth no problem. There are times though where the starter just can't crank the engine anymore and it never does start. Then if I put jumper cables onto my battery or even a small battery charger it will immediately start with normal faster starter speed like the battery required no charge and everything is fine!

At first this problem only happened when the weather got colder in the winter (I live in MN) and the car was sitting all night. This summer it maybe happened once or twice. All of a sudden this week it is happening throughout the day (it is getting colder now).

I have swapped battery with another good one to eliminate that (same problem different battery now). Alternator charges great. I have pulled the positive wire off battery and am finding no black current that could be drawing down the battery overnight. I replaced the corroded ground wire from battery. When purchasing the car it had a lot of corrosion on battery terminal hook up to battery, I replaced that (appears the previous kid owner had stereo system).

There is much toodoo on HAF about the main relay switch. I am suspicious of my main relay because of the starting issue and roughness on start perhaps related to fuel pump which is also affected by main relay. However, the main relay problems I read about here appear to happen while car is running or once the interior has warmed up. Once my engine starts it runs like a champ and never dies. Also, if this is main relay problem why would touching jumper cable to battery terminal allow it to immediately start?

Thanks if you're still reading up to this point!

 

How old are the spark plugs?

Try turning on the key....wait for the CEL to go off....then crank the engine.
The reason is to allow full fuel pressure and the injector will give a better spray pattern.
A nice fine mist is easier to ignite as opposed to a liquid dribble from low pressure.

I used to tell customers, turn on the key....put on the seat belt....then crank the engine.

 

Plugs were good last year back when I still had the problem. I'll check them again though. I'll also try turning the ignition on for a bit before cranking the engine. I don't see how either of these 2 items would affect the slow crank over of the engine though.

thanks for the reply!

 

My Bad....I thought the issue was the stumble at start.
The only other place to check might be the main ground at the trans housing
To prove an actual poor wire connection, jumper straight from the battery positive to the big positive connection of the starter.

 

I'll check it out and post here once I've done it. Pretty sure the ground wire I replaced went from Battery NEG to transmission. Could still be positive problem. I suspect it is something on the positive side since my ground should be good.

 

I might be a little off, but it's possible the starter is starting to seize. I don't know why it would do it more when its cold but its possible. The addition of more power allows the starter to pull more amperage and fire off the engine quicker. Check the draw on the starter, if it's higher than it should be (and I can't remember for the life of me how much its supposed to draw) than the starter could be going bad.

 

This morning she started fine! I checked the voltage on the battery before turning the key and it read 12.3. Let it sit all day, same thing (good battery voltage) started fine. Today we rose up above freezing, it's 34 degrees right now. I guess I will take it to autozone and see if they can tell me if the starter is pulling the right amps. Problem is I may have to let it sit in their lot overnight on a cold night. If I drove it there, went inside and came out with thier machine it may not find a problem since at that point it would start fine.

In the meantime I have implemented a temporary countermeasure to stop the bleeding. It's called a spare car battery in the trunk with long jumper cables that reach all the way from inside the trunk outside the car to the battery under the hood.

 

Still have starting problem!

Here's the latest:
1. Pulled starter and discovered when bench testing it would sometimes run real slow. Took it apart, sprayed brushes, cleaned armature, soaked solenoid in electrical contact cleaner. Ran consistently faster and sounded okay. Thinking starter could be the problem I decided not to reinstall it because of the inconsistent bench test.

2. Went to junk yard pulled starter off car there. Bench tested the starter before purchase. It was drawing 90 amps when spooling up. Had guy test my existing starter and it pulled 100 amps. Due to possible intermittent problem I still don't trust existing starter so I installed junk yard starter.

3. Still found starting problem with new (used) starter. Removed solenoid signal wire from starter, jump started positive wire straight from battery. Same thing, engine turning over slow.

4. Discovered loose negative terminal and crimp connection to terminal (universal terminal from walmart). Tightened negative connections and car started great. Fast turnover of engine. Car even started after sitting overnight although sounded a little slower. Car started okay for 3 days. Now again today after sitting for 1.5 days same slow engine crank over. Checked termnal connections and tightened up extra to make sure good, cleaned both battery posts, still slow cranking and no start.

I am now recalling that when I got car year ago there was a relay in the fuse box under hood that would click rapidly at times when car turned off with key out of ignition. Perhaps this is an indicator to someone of a possible cause to my troubles? I'm at point of taking to Autozone for them to check current draw when cranking engine. Even if Autozone tells me I am not pulling enough amps (which must be the case even with testing I believe) I will still have to figure out why. Perhaps the large positive wire that runs to my starter is burned under the insulation? I have ohmed out that wire, and the positive that runs from battery to fuse box along with both ground cables and they all indicate 0 ohms on multimeter. I would think that if problem is burned wire I would read some resistance on my little multimeter?

 

Your little multimeter may not read real low resistances correctly. Thats the territory of expensive meters. That big wire needs to carry lots of current during starting. My $230 Fluke 179 still doesnt have real good measurement uncertainty down there.

Besides, a corroded connection can can behave very differently depending on the current. The multimeter pulling 20 mA can measure it to be OK. Then the starter draws 120 amps & its a completely different story. Thin layers of oxide do some strange & wonderful things when polarized. Wonderful for transistors & diodes, but just plain BAD for carrying large current.

Better to measure VOLTAGE drop under those loads. Crank the starter & measure voltage between actual battery posts. Not the clamps, the actual lead posts.

Then do the same thing, from the negative post to the positive CLAMP. Then the other end of the positive wire. Work your way upstream;get it? Youre looking for some location where the voltage suddenly gets lower...

 

Don't I need a voltage drop to indicate there is current flowing? Any idea what voltage drop may be in a properly working system?

I was thinking if I read 10V under load between battery posts and then found 11V between NEG post and starter +connection that would indicate I am losing current in positive wire.