SaturnFans.com
what's new (beta) - classifieds - forums - photos


Go Back   SaturnFans.com Forums > Models > Saturn S-Series > S-Series Tech
Register FAQ Members List Groups Calendar Chat Room Search Today's Posts Mark Forums Read

Reply
 
Thread Tools Display Modes
Old 11-25-2018, 08:25 PM   #81
fdryer
Super Member
fdryer has a reputation beyond reputefdryer has a reputation beyond reputefdryer has a reputation beyond reputefdryer has a reputation beyond reputefdryer has a reputation beyond reputefdryer has a reputation beyond reputefdryer has a reputation beyond reputefdryer has a reputation beyond reputefdryer has a reputation beyond reputefdryer has a reputation beyond reputefdryer has a reputation beyond repute
 
fdryer's Avatar
 
Join Date: Jan 2006
Location: NYC
Posts: 43,525
 

2003 L-Series 3.0L Sedan
Default Re: hard starting 2001 SL1

PCM-B is a direct feed to part of the pcm. In this case its to erasable memory and other functions not open to anyone since service manuals don't dwell on sophisticated electronics. Functional diagrams are more than sufficient for most people familiar with advanced electronics without the over complication of extremely advanced electronics. Basically, all we need to know is power, signals going in and signals going out.

PCM-1 is switched power from the ignition switch. This would be power to the main part of the pcm to cycle circuits controlling cruise control, the EFI circuits controlling injectors and ignition.

Emissions is secondary to starting in the scheme of things. When power is fed from the ignition switch to pcm, the pcm powers up to run the fuel pump for two seconds and turns on injector and ignition circuits, waiting for crank signals to provide timing signals that synchronizes injector and spark at the appropriate time when the engine is rotated by the starter. The pcm already uses all the sensors to determine what fuel mixtures are needed when the engine's freezing, warm or hot. The iacv is automatically controlled and set to whatever position for correct idle speed under all temperatures and loads. Tps, map, intake, coolant, xmission temperature, input/output speed sensor, are what the pcm needs to determine air/fuel mixtures.

REWARD EXCELLENCE!

Add to fdryer's Reputation
Rate the quality of this post and help fdryer reputation points. Click the reputation button near the bottom left corner of this message box. Thank you!
fdryer is offline   Reply With Quote
SaturnFans.com Sponsored Links
Old 11-26-2018, 12:21 AM   #82
billr
Master Member
billr is a name known to allbillr is a name known to allbillr is a name known to allbillr is a name known to allbillr is a name known to allbillr is a name known to all
 
Join Date: Jul 2013
Posts: 5,126
Default Re: hard starting 2001 SL1

Consider getting better scanner, one that reads more of the live-data. Knowing what the initial (cranking) injector PW and IAC steps are set to may get you out of the weeds here. I am the one that fought the PCM 5V problem, it was severe enough to catch by just a voltmeter on the 5V, you may want to check that.

REWARD EXCELLENCE!

Add to billr's Reputation
Rate the quality of this post and help billr reputation points. Click the reputation button near the bottom left corner of this message box. Thank you!
billr is offline   Reply With Quote
Old 11-26-2018, 12:19 PM   #83
Ecomike
Member
Ecomike is a glorious beacon of lightEcomike is a glorious beacon of lightEcomike is a glorious beacon of lightEcomike is a glorious beacon of lightEcomike is a glorious beacon of light
 
Join Date: Jan 2011
Posts: 295

2001 SL1
Default Re: hard starting 2001 SL1

Quote:
Originally Posted by billr View Post
Consider getting better scanner, one that reads more of the live-data. Knowing what the initial (cranking) injector PW and IAC steps are set to may get you out of the weeds here. I am the one that fought the PCM 5V problem, it was severe enough to catch by just a voltmeter on the 5V, you may want to check that.
LOL, better scanner? I have a Snap-on MT-2500, with the 2001 cartridges.

Live data when the engine is running is all perfectly normal. But I am not sure if it will read data while cranking, or prestart-ignition switch in run mode sensor data. I think I tried that with the OBD-Blue tooth.....But I will check. I know the snap-on scanner works on 1987 Jeeps, engine off, ign switch in run position :-)

I solved a 12 year old problem on my 87 TPS that way :-)

Turned out uncle Bob had bent the throttle rod to the TB, and the TPS only went to 67% open (and so did the throttle body butterfly plate ). Every one had told me the engine was worn out, and that was why it had no power. LOL

I had a duplicate rig, and compared the control rods. 12 year old problem solved.

REWARD EXCELLENCE!

Add to Ecomike's Reputation
Rate the quality of this post and help Ecomike reputation points. Click the reputation button near the bottom left corner of this message box. Thank you!
Ecomike is offline   Reply With Quote
Old 11-26-2018, 01:56 PM   #84
billr
Master Member
billr is a name known to allbillr is a name known to allbillr is a name known to allbillr is a name known to allbillr is a name known to allbillr is a name known to all
 
Join Date: Jul 2013
Posts: 5,126
Default Re: hard starting 2001 SL1

OK, I also use an MT-2500, on OBD1, and know it will show a lot of parameters you seem to be guessing about. I can see cranking rpm, initial PW, spark timing and much more; all constantly from the time it connects with the PCM. Do you not see any of that? Is the MT-2500 less capable with OBD2 than OBD1?

REWARD EXCELLENCE!

Add to billr's Reputation
Rate the quality of this post and help billr reputation points. Click the reputation button near the bottom left corner of this message box. Thank you!
billr is offline   Reply With Quote
Old 11-26-2018, 01:59 PM   #85
fdryer
Super Member
fdryer has a reputation beyond reputefdryer has a reputation beyond reputefdryer has a reputation beyond reputefdryer has a reputation beyond reputefdryer has a reputation beyond reputefdryer has a reputation beyond reputefdryer has a reputation beyond reputefdryer has a reputation beyond reputefdryer has a reputation beyond reputefdryer has a reputation beyond reputefdryer has a reputation beyond repute
 
fdryer's Avatar
 
Join Date: Jan 2006
Location: NYC
Posts: 43,525
 

2003 L-Series 3.0L Sedan
Default Re: hard starting 2001 SL1

Quote:
Originally Posted by Ecomike View Post
.....I solved a 12 year old problem on my 87 TPS that way :-)

Turned out uncle Bob had bent the throttle rod to the TB, and the TPS only went to 67% open (and so did the throttle body butterfly plate ). Every one had told me the engine was worn out, and that was why it had no power. LOL

I had a duplicate rig, and compared the control rods. 12 year old problem solved.
Maybe he was Eco Bob........ detuning the engine...

REWARD EXCELLENCE!

Add to fdryer's Reputation
Rate the quality of this post and help fdryer reputation points. Click the reputation button near the bottom left corner of this message box. Thank you!
fdryer is offline   Reply With Quote
Old 11-26-2018, 06:52 PM   #86
Ecomike
Member
Ecomike is a glorious beacon of lightEcomike is a glorious beacon of lightEcomike is a glorious beacon of lightEcomike is a glorious beacon of lightEcomike is a glorious beacon of light
 
Join Date: Jan 2011
Posts: 295

2001 SL1
Default Re: hard starting 2001 SL1

LOL. Uncle Bob / Eco Bob... reminds me of the old Vern videos.

All I know is it was one of Longest, time wise, oddest , simplest (LOL) problems I had to solve.


No where in the FSM does it tell folks to check the throttle linkage to see if Uncle Bob bent it, LOL. It was only 3/8" of sweep that was missing, so it looked totally normal and fully open.

I am known for never giving up on debugging things and fixing them.

I am one of the people that folks bring what they think are unsolvable problems to, problems they gave up on. I love the challenge.

REWARD EXCELLENCE!

Add to Ecomike's Reputation
Rate the quality of this post and help Ecomike reputation points. Click the reputation button near the bottom left corner of this message box. Thank you!
Ecomike is offline   Reply With Quote
Old 12-24-2018, 09:27 PM   #87
Ecomike
Member
Ecomike is a glorious beacon of lightEcomike is a glorious beacon of lightEcomike is a glorious beacon of lightEcomike is a glorious beacon of lightEcomike is a glorious beacon of light
 
Join Date: Jan 2011
Posts: 295

2001 SL1
Default Re: hard starting 2001 SL1

Had to replace my water pump, pulley wobble, was starting to leak, shaft bearing, it was a Durajunk 4 year old maybe 20,000 mile pump.

Where is the CPS in these rigs?

I solved the blue tooth scanner issue I had, seems the cell phone-Torque combo has three blue tooth places that must all be activated.

Not just two. Silly me.

No hard/no starts in weeks now. The cloaked gremlins are hibernating again.

REWARD EXCELLENCE!

Add to Ecomike's Reputation
Rate the quality of this post and help Ecomike reputation points. Click the reputation button near the bottom left corner of this message box. Thank you!
Ecomike is offline   Reply With Quote
Old 12-25-2018, 01:01 AM   #88
Greg1
Senior Member
Greg1 will become famous soon enough
 
Greg1's Avatar
 
Join Date: Jul 2001
Location: Thousand Oaks, CA
Posts: 1,321
 

1997 SW2
1998 SL2
Default Re: hard starting 2001 SL1

The CPS is located on the rear of the engine above the starter.

...
97 SW2 5-Sp 273k -mine
02 SC2 5-Sp 67k - best friend's

REWARD EXCELLENCE!

Add to Greg1's Reputation
Rate the quality of this post and help Greg1 reputation points. Click the reputation button near the bottom left corner of this message box. Thank you!
Greg1 is offline   Reply With Quote
Old 12-25-2018, 01:54 PM   #89
Ecomike
Member
Ecomike is a glorious beacon of lightEcomike is a glorious beacon of lightEcomike is a glorious beacon of lightEcomike is a glorious beacon of lightEcomike is a glorious beacon of light
 
Join Date: Jan 2011
Posts: 295

2001 SL1
Default Re: hard starting 2001 SL1

Quote:
Originally Posted by Greg1 View Post
The CPS is located on the rear of the engine above the starter.
Never seen the starter either? Is it buried on the firewall side? Ugh...

I guess if the problem was the CPS, clearing the PCM memory by disconnecting the battery would not be the instant fix (of a dying CPS) I have seen off and on for year now.

Gotta be something with IAC Idle air control valve, dirt or....

Do you all ever oil/lube them and clean them?

REWARD EXCELLENCE!

Add to Ecomike's Reputation
Rate the quality of this post and help Ecomike reputation points. Click the reputation button near the bottom left corner of this message box. Thank you!
Ecomike is offline   Reply With Quote
Old 04-14-2019, 01:41 PM   #90
Ecomike
Member
Ecomike is a glorious beacon of lightEcomike is a glorious beacon of lightEcomike is a glorious beacon of lightEcomike is a glorious beacon of lightEcomike is a glorious beacon of light
 
Join Date: Jan 2011
Posts: 295

2001 SL1
Default Re: hard starting 2001 SL1

Still having to occasionally wipe all KAL memory by draining the computer memory, by disconnecting the battery and shorting the cables for 20 seconds to solve a repeated low RPM start attempt that dies. Only fix has been to clear the PCM memory.

Could that be resetting a PCM memory issue of where to park the IAC position and solve the problem?

Been like this for a very long time. Most of the time 9/10ths, it is a hot restart issue. If it was a temp sensor, or TPS issue, clearing PCM KAL memory would not, IMHO, immediately fix it. Almost never does it on a cold restart, but it has done 5 hours later, so that further debunks trying to call it strictly a temp issue like heat soak of injectors, or Temp sensors.....

I have run some tests, that convince me it is not the TPS. That leaves my earlier idea of a stuck open EGR, but I am evening doubting that idea for now. Looking for any other possible usual suspects.

Once reset in sometimes takes weeks or months to do it again. I only drive it once a week some weeks, with about 3 restarts on that day. Some weeks I may make one trip/day.

Weather has warmed up and I am making plans to dig into this issue again this spring. Thanks for every ones help here.

REWARD EXCELLENCE!

Add to Ecomike's Reputation
Rate the quality of this post and help Ecomike reputation points. Click the reputation button near the bottom left corner of this message box. Thank you!
Ecomike is offline   Reply With Quote
Old 04-15-2019, 08:52 PM   #91
fdryer
Super Member
fdryer has a reputation beyond reputefdryer has a reputation beyond reputefdryer has a reputation beyond reputefdryer has a reputation beyond reputefdryer has a reputation beyond reputefdryer has a reputation beyond reputefdryer has a reputation beyond reputefdryer has a reputation beyond reputefdryer has a reputation beyond reputefdryer has a reputation beyond reputefdryer has a reputation beyond repute
 
fdryer's Avatar
 
Join Date: Jan 2006
Location: NYC
Posts: 43,525
 

2003 L-Series 3.0L Sedan
Default Re: hard starting 2001 SL1

With too many posts in this thread, it may help to list all parts replaced to address this issue.

REWARD EXCELLENCE!

Add to fdryer's Reputation
Rate the quality of this post and help fdryer reputation points. Click the reputation button near the bottom left corner of this message box. Thank you!
fdryer is offline   Reply With Quote
Reply



Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
2001 Hard Starting in Cold Weather dlacacres S-Series Tech 9 04-07-2014 05:51 PM
Hard starting midwest S-Series General 2 06-27-2009 12:54 PM
Hard Starting SL jdsdls S-Series Tech 0 06-24-2009 11:53 AM
Hard starting 97' SL2 rudy S-Series Tech 7 03-13-2005 08:44 PM
Hard Starting Vue Dar Vue General 15 02-26-2004 10:58 AM


All times are GMT -4. The time now is 02:43 AM.

Advanced Forum Search | Advanced Photo Search


Powered by vBulletin® Version 3.8.9
Copyright ©2000 - 2020, vBulletin Solutions, Inc.
SaturnFans.com. The Saturn Enthusiasts Site.