02 Monte Carlo SS 3.8, Intermittent No crank

tunabreath · April 22, 2015

2002 Monte Carlo SS 3.8, no supercharger. 65k miles.

Having an intermittent no-crank condition. Sometimes the starter solenoid will click, sometimes it won't. The starter is a 2 week old reman from Advance Auto.

Here's what I have done -

-Cleaned all connections including battery terminals, grounds, leads to starter and starter housing to block.
-Tested all wires for voltage drop and high resistance, nothing abnormal found.
-Verified operation of starter cranking relay, swapped it with a known good one. Checked voltage at relay pins in junction block, all good.
-Tested all fuses and checked for loose fuses.

-ignition switch was replaced 4 months ago, took it apart and inspected contacts, all good no corrosion or arcing.
-jumped the battery terminal on solenoid to S terminal on solenoid. SOMETIMES it cranks, sometimes nothing, not even an arc.
-checked for voltage at S terminal while ignition in START, couldn't get reading even when starter cranks or doesn't crank. Too quick for meter to pick up?
-removed starter from vehicle, bench tested it. Can not get it to act up, works OK.

-battery maintains 10-11v while cranking.

-Engine is not seized.

2 odd things-

Once in a while when the starter does function on the vehicle you will get a few sparks falling from near starter area, too quick to see where from.

Once, when holding ignition to START and nothing was happening, a RED/BLK wire heated up and burnt insulation off. This wire comes from the ignition module and runs to PCM. The area where it burnt up was at connector C110 located under the engine cover. It is the "LOW REFERENCE" to PCM. Why would there be that much current flowing through what is essentially a ground wire and why has it not blown a fuse? On a hunch, I swapped in a different ignition module thinking something was internally shorted inside this one (replaced it due to a phantom misfire 2 weeks ago), but no change. Back to the new module.

I'm lost. Right now the starter is off the vehicle and I am letting it sit to see if I can get it to malfunction while bench testing.

Also, no Security light flashing. Just the normal pulse when key is ON position from BATTERY to SECURITY which is normal.

Any help is appreciated!

gmtech4 · April 22, 2015

Wrong site !!!

See a tech , you've done all your skill level can do... Sorry

Try alldata . Com

SILVER SLED · April 23, 2015

Could have a bad body control module (BCM). Those cars were notorious for them. Could be a battery cable also. Problem is there is no check for the BCM.

gmtech4 · April 23, 2015

Could have a bad body control module (BCM). Those cars were notorious for them. Could be a battery cable also. Problem is there is no check for the BCM.

BCM doesn't start the car ...

Doug_Scott · April 23, 2015

If you are getting sparks showering down from the starter area there must be something visible to help you diagnose it. I would pay the most attention to the positive starter cable. Do not just assume that because the terminal is clean, that the cable is good. Remove the cable completely, and do a good inspection of the cable, looking at the insulation around the cable to make sure it is smooth, with no bulging happening. Sometimes a cable will develop a small hole or split allowing water to get in to it. Once that happens the wire starts to corrode inside the cable. Make sure you remove the cable from the car to properly inspect it, and make sure you have the entire cable that goes from battery to starter. If it has a connector half down, pull both cables.. Cable is 13 years old, maybe time to just go ahead and change it. Also do the same for the ground cable.

SILVER SLED · April 23, 2015

BCM doesn't start the car ...

It doesn't start the car, but it can inhibit the car from starting, more specifically cranking.

tunabreath · April 23, 2015

I have had the starter off the car now for 24 hours. I have probably engaged it several dozen times without an issue.

I have a subscription to Chilton's and have the starting circuit diagram. Everything checks out as it should.

This starter is going back on the car for one more round of testing. I have no idea what else to check.

Doug_Scott · April 23, 2015

I have had the starter off the car now for 24 hours. I have probably engaged it several dozen times without an issue.

I have a subscription to Chilton's and have the starting circuit diagram. Everything checks out as it should.

This starter is going back on the car for one more round of testing. I have no idea what else to check.

Did you get the cables off the car and test/inspect them carefully? If you did see sparks showering down then you have a high amperage short. The only cables that are able to carry enough amperage to allow sparks to shower are the main battery cables, both positive and ground.

tunabreath · April 23, 2015

Might have got this thing figured out.

I was lucky enough to catch where the spark came from. I found another ground on the trans bell housing. It was a long stud and the nut seemed tight but it actually had a thread or 2 more to go.. It was pretty corroded but not terrible. I took the leads off, cleaned the leads and the mating surface. I started it three times, going to let it sit for a while and see what happens. Thanks to all.

gmtech4 · April 24, 2015

It doesn't start the car, but it can inhibit the car from starting, more specifically cranking.

Whatever you say right fighter

00Silverado4x4 · April 24, 2015

Have the battery tested? The battery may be getting weak if not a bad cell or something like that. Just a thought.

SILVER SLED · April 24, 2015

Whatever you say right fighter

Don't take it so hard. We all make mistakes.

gmtech4 · April 25, 2015

Don't take it so hard. We all make mistakes.

I didn't make the mistake

SILVER SLED · April 25, 2015

You need to get over yourself. It's not healthy. You can live in denial all you want, but it's not gonna get this guys car fixed. We've replaced many BCM's for an intermittent no crank. Do yourself and the op a favor and do some research before running your internet mouth off without a clue.

I didn't make the mistake

gmtech4 · April 25, 2015

You need to get over yourself. It's not healthy. You can live in denial all you want, but it's not gonna get this guys car fixed. We've replaced many BCM's for an intermittent no crank. Do yourself and the op a favor and do some research before running your internet mouth off without a clue.

Relax