Hard/slow starting
#1
Hard/slow starting
I dug around on the forums a little and did some testing/maintenance before posting this so, hopefully, it will be a little easier to diagnose.
I don't think that this has a lot to do with it but I'll point it out anyway... my difficulty starting began after replacing the airbags with coilover springs. I've pulled the relevant fuses so I think it's unrelated but thought I'd toss it out there for completeness.
Sometimes, when trying to start it up it will take several tries to get the engine to actually start. The problem is intermittent but here's what happens: when I try to start the engine the engine turns over slowly like I'm on an almost dead battery. I return the key to the first position and attempt to start again usually resulting in a normal crank and a quick start. It sometimes takes three attempts to get it started but it always starts eventually. It seems to happen more often when hot but my girlfriend says it has happened to her when it is completely cool after sitting in front of the house all night. There are no codes showing or pending.
So far I've tested voltages/amperage with it off, off with lights on, running and running with accessories going and everything checks out. Good voltages across the board and I've recreated the issue with a known good battery. I've cleaned the terminals and connectors on the battery even though they were completely free of corrosion. I did the same with the connection for the negative lead down on the engine block and on the big cables going into the fuse box. I ran out of daylight and time before I could clean the ground around the starter but have otherwise hit all of the grounds mentioned above. Have I missed any?
At this point I'm thinking starter. The symptoms don't match the crank position sensor but I suppose that could be an issue as well.
Any guesses would be great. Thanks for your help in advance.
I don't think that this has a lot to do with it but I'll point it out anyway... my difficulty starting began after replacing the airbags with coilover springs. I've pulled the relevant fuses so I think it's unrelated but thought I'd toss it out there for completeness.
Sometimes, when trying to start it up it will take several tries to get the engine to actually start. The problem is intermittent but here's what happens: when I try to start the engine the engine turns over slowly like I'm on an almost dead battery. I return the key to the first position and attempt to start again usually resulting in a normal crank and a quick start. It sometimes takes three attempts to get it started but it always starts eventually. It seems to happen more often when hot but my girlfriend says it has happened to her when it is completely cool after sitting in front of the house all night. There are no codes showing or pending.
So far I've tested voltages/amperage with it off, off with lights on, running and running with accessories going and everything checks out. Good voltages across the board and I've recreated the issue with a known good battery. I've cleaned the terminals and connectors on the battery even though they were completely free of corrosion. I did the same with the connection for the negative lead down on the engine block and on the big cables going into the fuse box. I ran out of daylight and time before I could clean the ground around the starter but have otherwise hit all of the grounds mentioned above. Have I missed any?
At this point I'm thinking starter. The symptoms don't match the crank position sensor but I suppose that could be an issue as well.
Any guesses would be great. Thanks for your help in advance.
#3
Mike, thanks for the thoughts.
It's a fairly new battery so I switched it out with a different new battery to rule out battery issues. Even with a different battery the problem remained. Still, I'll put it on my trickle charger tonight and see if that does it.
I put Magnecor 8mm wires in last winter so they are, maybe, eight months old?
This is probably a stupid question but would a failing fuel pump cause the engine to turn over slowly? When it's acting up the engine turns over very slowly on the first attempt... just like I've got a battery that barely has enough juice. To put it another way, the first time this happened I fully expected to hear *tick tick tick* instead of the engine turning over when I tried to start it the second time. Still, I'll test the fuel pressure to see if there is anything wrong.
It's a fairly new battery so I switched it out with a different new battery to rule out battery issues. Even with a different battery the problem remained. Still, I'll put it on my trickle charger tonight and see if that does it.
I put Magnecor 8mm wires in last winter so they are, maybe, eight months old?
This is probably a stupid question but would a failing fuel pump cause the engine to turn over slowly? When it's acting up the engine turns over very slowly on the first attempt... just like I've got a battery that barely has enough juice. To put it another way, the first time this happened I fully expected to hear *tick tick tick* instead of the engine turning over when I tried to start it the second time. Still, I'll test the fuel pressure to see if there is anything wrong.
Last edited by longjon76; 07-25-2012 at 05:00 PM.
#4
Okay, I tested the fuel pressure (that was no fun) and got 2.3 bar. A little on the low side but acceptable, right?
I also cleaned up a few more grounding points. While I was mucking around by the battery box I found a medium gauge wire that isn't connected to anything. I know I've never touched it so I doubt it's the problem but I've included a picture of it anyway.
It follows along the passenger side, across the firewall and through the firewall on the driver's side here:
Is the wire pictured possibly related or is it a red herring?
I also cleaned up a few more grounding points. While I was mucking around by the battery box I found a medium gauge wire that isn't connected to anything. I know I've never touched it so I doubt it's the problem but I've included a picture of it anyway.
It follows along the passenger side, across the firewall and through the firewall on the driver's side here:
Is the wire pictured possibly related or is it a red herring?
#5
#6
drowssap, there's nothing obvious up front. In fact, it was pretty much bone stock when I bought it. Once I figure out why it's being so weird about starting I'll trace it through the firewall and see where it goes.
So, basically, that is not something that, left disconnected, will impact the hard start condition?
So, basically, that is not something that, left disconnected, will impact the hard start condition?
#7
I have no doubt Mike is a wealth of information, but just to offer an alternative, your symptoms sound a lot like mine in the weeks leading up to my starter dying. I kept scratching my head right up until the morning it quit working. I had tested voltages, battery, fuel pressure, you name it. Installed the new starter and I was good to go.
#8
I hate it when people post problems but never follow up with the solution. So...
The slow start condition continued with no real worsening. Then I tried to start it immediately after my girlfriend drove it. The engine turned over very slowly and then stopped. It sounded exactly like a bad battery.
I pulled the negative battery cable and the heat shield. Then I removed the large nuts on the solenoid and the signal wire. I shorted the two sides of the solenoid to try and narrow down whether it was starter or solenoid failing, and when I reconnected the battery the starter spun freely. I took everything back apart and gave the terminals and grounds a thorough cleaning. Put everything back together and it started right up.
It was probably cleaning the grounds that really did it. I'm still going to start saving for a new AB starter. Anyway, problem solved. Thanks to everyone that weighed in.
The slow start condition continued with no real worsening. Then I tried to start it immediately after my girlfriend drove it. The engine turned over very slowly and then stopped. It sounded exactly like a bad battery.
I pulled the negative battery cable and the heat shield. Then I removed the large nuts on the solenoid and the signal wire. I shorted the two sides of the solenoid to try and narrow down whether it was starter or solenoid failing, and when I reconnected the battery the starter spun freely. I took everything back apart and gave the terminals and grounds a thorough cleaning. Put everything back together and it started right up.
It was probably cleaning the grounds that really did it. I'm still going to start saving for a new AB starter. Anyway, problem solved. Thanks to everyone that weighed in.
#10
See attached photo. Anything with the wires on the starter can also be suspect. The big wire is plus battery, so if tinkering disconnect battery. My clamp-on amp meter shows a draw of almost 300 amps from the starter, so by Ohms law, volts=amps X resistance, and 6 volts = 300 amps X 0.02 ohms. 6 volts of drop for 2/100 of an ohm resistance, which can be at one connector, or at several points added up, including the ground (earth) path through the frame connection points.
Point is that every connection involving the starter needs to be very clean and tight.
The there is the contact resistance of the solenoid as well.
Mine was slow, and hard to engage, replaced starter and happy days returned. Note that actual replacement of the starter is not a happy task, need several long extensions and work from front of axle.
Point is that every connection involving the starter needs to be very clean and tight.
The there is the contact resistance of the solenoid as well.
Mine was slow, and hard to engage, replaced starter and happy days returned. Note that actual replacement of the starter is not a happy task, need several long extensions and work from front of axle.