Use the starter, No / Pop the clutch, Yes

[ortegsa]

My '98 Sl with 111,000 has intermittently quite starting in the morning. The starter cranks strong but engine does not start. When I pop the clutch it starts up fine. But if it sits over night it will not start gotta pop the clutch.

Checks;
Battery/Alternator is fine 12.75V 14V running Diode is good
Fuel Pump pressurizes the system
Ignition coil has battery voltage at connector
Cleaned ground connection around battery area
Battery voltage when starter is turning stays around 12V ( thought maybe the starter was going bad and drawing down the voltage to PCM)

This morning after doing more checks I gave up and popped the clutch to start it. Turned it off right away. It cranked fine and started. Just went to check it again 20 minutes later and it still starts right up?!?!?!

[fdryer]

Originally Posted by ortegsa

My '98 Sl with 111,000 has intermittently quite starting in the morning. The starter cranks strong but engine does not start. When I pop the clutch it starts up fine. But if it sits over night it will not start gotta pop the clutch. This morning after doing more checks I gave up and popped the clutch to start it. Turned it off right away. It cranked fine and started. Just went to check it again 20 minutes later and it still starts right up?!?!?!

So which is it, a starter or cranking but no firing up problem? If its both this may be an engine coolant temperature sensor (ECTS) problem. Look in the How-to library's first two posts about it, pictures and procedures included. The original sensor fails and tends to richen the mixture requiring flooring the gas pedal to clear the flooding tendency or leans out the mixture resulting in backfiring into the intake manifold. Either way, the coolant sensor is the cause erratic engine running.

And welcome to Saturnfans!

[MikeNW]

My experience: I had a Honda Shadow 1100.
The battery was notoriously tiny. As it got older, even after charging, it would crank and crank but wouldn't start the engine.
I had to push start it until I bought its annual $80 battery.
I believe that there wasn't enough voltage to fire the electronic ignition AND crank the bike.
Suspect something like that with yours.

What is the battery V at rest?

[ortegsa]

Originally Posted by MikeNW

My experience: I had a Honda Shadow 1100.
The battery was notoriously tiny. As it got older, even after charging, it would crank and crank but wouldn't start the engine.
I had to push start it until I bought its annual $80 battery.
I believe that there wasn't enough voltage to fire the electronic ignition AND crank the bike.
Suspect something like that with yours.

What is the battery V at rest?

Standing voltage is 12.75

[OldNuc]

ortegsa

It sounds like the battery and charging system are in good condition and not a problem. It also sounds like the starter is not your problem either. Neither are the power cables. So, now fdryer made the best suggestion as where to start. Go buy a nice new ECTS and replace the existing one. Also very carefully inspect the connector for any signs of green corrosion. If you find any an Intake Air Temperature sensor connector up by the left headlight is a good replacement, get one from your favorite junk yard. The ECTS can cause all kinds of problems, none of which leave much of a clue.

[ortegsa]

Well I put in a new ECTP. Good news the car runs even better than before, Bad news it still would not start from the starter this a.m. Popped the clutch and went to get a bagel and paper no problem and has started from the starter all morning since.

Other observations done this a.m. after no start but before popping the clutch:
- Disconnected and reconnected all PCM harnesses (after disconnecting battery)
- Replacing the ECTP turned off the SES light
- IAT has the 5 volt reference voltage with ignition on
- O2 sensor does not have the 0.5 volt reference (but I am using an analog meter set at 0-10V I would think that I would see it move at least a little but will get a digital one and try again) measured the O2 before and after popping the clutch to start the car

[OldNuc]

When you pop the clutch are you also stepping on the gas by any chance?

[ortegsa]

Never really thought about it but I guess yes. It is more like sitting on a hill and taking off, do gas and clutch at around the same time. Once I get rolling down the driveway, not really going fast, only rolling around 5 feet I pop the clutch and give it a little gas at the same time. I'm not pushing the peddle to the floor and the RPM doesn't race when it starts.

[Dr B]

The oxygen sensor will not have the 5 volt reference, it makes its own voltage (generator) ,which it feeds the PCM.

Seems like you have a problem inside the ign. switch assembly.

[ortegsa]

Thanks Dr. B
Reading the Haynes manual I was under the impression when they said probe the harness end that it was the end coming from the PCM. Dah! that makes no sense with a one wire sensor

[fdryer]

Uhhh, he posted 0.5v, not 5v from the O2 sensor.

ortegsa, why you're measuring the O2 voltage is a mystery since it won't have any bearing on starting problems that you're having. A cold engine doesn't use the O2 sensor until way after the engine is fully warmed up. Cold engine running without the O2 sensor = open loop operation, engine warmed up and exhaust at 600F+ = O2 sensor operating/closed loop mode, normal engine running.

The replacement coolant sensor helped with starting but removing the spark plugs may reveal that they may be fouled from the extra rich mixture. Clean or replace them with plain copper plugs if necessary.

[ortegsa]

I still have the initial problem, car will not start with the starter but will start when a roll and pop the clutch. The ECTS helped it to run smoother, the plugs were checked yesterday, have 20,000 miles on them and show signs of normal combustion. I can replace them but I am still confused that my Satty starts and runs fine throughout the day except for when I first try to start it in the morning.

[fdryer]

OK, if the plugs look fine then the next check would be the entire ignition system; ignition module, coils, and wires. Yes, even though the ignition system is working, is there a possibility of morning dew/moisture shorting the ignition system? Its a stretch but you're consistently describing that the starting fails only in the morning. Overnight moisture? Popping the clutch doesn't strain the electrical system the way the starter does by taking voltage away from the ignition system. Full battery voltage is available and the ignition system is just waiting for the cps to generate timing signals before the PCM starts running the EFI system. Cleaning up corrosion on the ignition module and coils, replacing the plug wires, all may help with ensuring the ignition system is not shorting from morning dew.

[BarnOwl]

Originally Posted by ortegsa

I am still confused that my Satty starts and runs fine throughout the day except for when I first try to start it in the morning.

Try something for me. Instead of hopping in the car and just trying to start it. Turn the key to run and wait a few seconds then try to start it. I suspect the check valve in your fuel pump is allowing the fuel pressure to bleed down overnight. When you push start it, you turn the key to run for a few seconds before kicking it over too.

[OldNuc]

Originally Posted by ortegsa

Never really thought about it but I guess yes. It is more like sitting on a hill and taking off, do gas and clutch at around the same time. Once I get rolling down the driveway, not really going fast, only rolling around 5 feet I pop the clutch and give it a little gas at the same time. I'm not pushing the peddle to the floor and the RPM doesn't race when it starts.

You might want to try this. The next morning right before you crank it over slightly crack the throttle open. Try that along with barnOwls suggestion to let the fuel pump prime the system before you crank. Do each test on separate mornings.

[ortegsa]

OldNuc and Barn Owl
I have done both of those. Waiting a few seconds was one the first things I tried thinking I wasn't getting fuel. I can hear the pump whirr. Also one day I relieved the pressure first out the schrader valve then turned the key then checked to see if I had pressure and did. With that I ruled out the fuel pump and filter. As for starting with the throttle just cracked I have not tried but have tried cranking with it more than cracked with no luck. But when I popped the clutch and it started it did smell rich.

fdryer gave a recommendation to chase down the ignition system. So lucky guy that I am my Dear Satty didn't start this a.m. ( don't laugh remember this is an intermittent problem that doesn't always give me the opportunity to troubleshoot) So I got my neighbor to crank the engine while I probed the Ign Module 6 pin conn. I probed the white wire with the thought that I should see some voltage coming through it. If not there is a strong possibility my CPS is faulty. No voltage showed. Popped the clutch, got it going, turned it off and then probed again while trying to start. Saw voltage and it started. Then proceeded to remove and clean all dirt from Ign coil and module. Also tonight i am putting new plugs and wires in, it's not due yet but hey it can't hurt.

Next time it will not start I have two things I was going to try. Pull the plug wires and see if the coils spark and secondly pop the clutch with the ign off and then try to start it to see if it is the jarring sensation that is getting something loose.

Will post what happens

Am still looking for good theories, please keep them coming.

Thanks. ortegsa

[fdryer]

The theory is that you'll eventually track down the problem with the way your going about it.

[rc1488]

No one has suggested a bad CPS! This is the first thing to come to mind after the a faulty check valve in the fuel pump.
Easy test for a faulty CPS: http://youtube.com/watch?v=pUMGFnK29B8
video by richpin

[ortegsa]

Well for the first time it did not start in the afternoon leaving work (thank goodness there is a slight slope in the parking lot at work) so I tried popping the clutch w/ the ignition off, no joy. Did it again and still no joy. Turned on the ignition popped the clutch and drove on to Autozone for new plugs and wires. Put those in tonight. We'll see what happens in the a.m.

fdryer your comment reminds me of a quote I once read, "Everything will be okay in the end. If everything is not okay, it's not the end"

[fdryer]

"The theory is that you'll eventually track down the problem with the way your going about it."

"Everything will be okay in the end. If everything is not okay, it's not the end"

And, "Are we there yet?"