No injector pulse - GM Forum - Buick, Cadillac, Chev, Olds, GMC & Pontiac chat


Buick When starting new posts, please specify YEAR, MAKE, MODEL, ENGINE type, and whatever modifications you have made.

Reply
 
 
 
Thread Tools Search this Thread
Old 05-13-2016, 05:11 PM   #1
Member
Posts like a V-Tak
Thread Starter
 
Join Date: Oct 2010
Location: Georgia
Posts: 78
Thanked 15 Times in 14 Posts
joeld will become famous soon enough
Default No injector pulse

Hey guys, I need some help! Car is a 1994 Le Sabre, 87K miles. Car has been in the family since new, I'm the only person to ever work on it which has been very rare. Car is in really nice condition.

Car was driven four days ago on short trip(2 MILES), no problems. Attempted to start car Tuesday, cranks over fine, no start.

Spark plugs are firing with a good fat spark.
Fuel pressure is 42 lbs
Have power at the injector plug with ing switch on
Checked with noid light in inj plug, cranked engine and no pulse
No trouble code stored, checked with scanner

Spent several hours last few days on the web looking for clues, found lots of conflicting info.

Started to change the Crankshaft Position Sensor, but read that if the plugs are firing, the CPS is good? Any thoughts on this.

One other detail that is a little odd, both coolant fans are coming on when the ingnition switch is in the on/run position.

Thanks
Joel
joeld is offline   Reply With Quote
Old 05-13-2016, 09:41 PM   #2
Senior Member
True Car Nut
 
rjolly87's Avatar
 
Join Date: Jun 2003
Location: Las Cruces, NM
Posts: 6,857
Thanked 298 Times in 246 Posts
rjolly87 has a brilliant futurerjolly87 has a brilliant futurerjolly87 has a brilliant futurerjolly87 has a brilliant futurerjolly87 has a brilliant futurerjolly87 has a brilliant futurerjolly87 has a brilliant futurerjolly87 has a brilliant futurerjolly87 has a brilliant futurerjolly87 has a brilliant futurerjolly87 has a brilliant future
Default

Cooling fans may or may not be related, but that is odd. There are several things that can cause them to run when cold, a few of which can relate to your problem.

What does the security light do on this car? Does it stay steady, flash continuously, or flash a few times and then go out?

Do you have the ability to scan codes on this car? Is anything else acting funky on the dash such as warning lights, radio, climate control, etc?
rjolly87 is offline   Reply With Quote
Old 05-13-2016, 09:53 PM   #3
Member
Posts like a V-Tak
Thread Starter
 
Join Date: Oct 2010
Location: Georgia
Posts: 78
Thanked 15 Times in 14 Posts
joeld will become famous soon enough
Default

Security light comes on when ign switch is in "run" position. Stays on steady for approx 10 seconds and goes out.
Yes, I did scan for codes and there are none.
No climate control, this is a basic LeSabre. And nothing else funky. Everything else seems to be OK.
This is really a surprising problem with the car! Last time we drove it everything was just fine.

Thanks
Joel
joeld is offline   Reply With Quote
Old 05-14-2016, 01:09 AM   #4
Senior Member

Posts like a Turbo
 
Join Date: Feb 2015
Location: Earth
Posts: 246
Thanked 39 Times in 37 Posts
CathedralCub has a spectacular aura aboutCathedralCub has a spectacular aura aboutCathedralCub has a spectacular aura about
Default

Yeah weird. You've covered the basics I'd cover.

87,000 miles in 22 years sounds like lots of short trips therefore heat cycles. If it hasn't ever had a CPS replaced I'd go ahead and replace it and see what happens. Perhaps plugs are indeed firing, but in the wrong order because CPS is giving bad information? Perhaps CPS signal is bad enough that injectors aren't firing or somesuch?

Either way it'd be good insurance so you don't find yourself someday saying [aw shucks I wish I had replaced the CPS after all . . . before replacing the flux capacitor, inertial dampeners, and dilithium crystals]
CathedralCub is offline   Reply With Quote
The Following User Says Thank You to CathedralCub For This Useful Post:
joeld (05-15-2016)
Old 05-14-2016, 11:21 AM   #5
Senior Member

Certified GM nut
 
Tech II's Avatar
 
Join Date: Feb 2014
Location: Worcester, Ma.
Posts: 2,150
Thanked 785 Times in 614 Posts
Tech II has a reputation beyond reputeTech II has a reputation beyond reputeTech II has a reputation beyond reputeTech II has a reputation beyond reputeTech II has a reputation beyond reputeTech II has a reputation beyond reputeTech II has a reputation beyond reputeTech II has a reputation beyond reputeTech II has a reputation beyond reputeTech II has a reputation beyond reputeTech II has a reputation beyond repute
Default

Sure you can read ALL codes? most scan tools/readers, only read "P" codes....

No injector pulse means, problem with Security system, bad ICM(no ref signal), or bad PCM.....

If you have spark, the crank sensor is ok.....
Tech II is offline   Reply With Quote
The Following User Says Thank You to Tech II For This Useful Post:
joeld (05-15-2016)
Old 05-14-2016, 11:51 AM   #6
Member
Posts like a V-Tak
Thread Starter
 
Join Date: Oct 2010
Location: Georgia
Posts: 78
Thanked 15 Times in 14 Posts
joeld will become famous soon enough
Default

Thanks for the replies.
I started to change the crankshaft position sensor but after some reading, most
of the info I found said that if there'* spark then the crank sensor is working.

With the coolant fans coming on as soon as the ing switch is turned to run position, I'm leaning towards the ECM.

I'm not 100% sure all codes/info is being displayed by my scanner. I've used this ACTRON for many years on different cars. I was just glad it would actually "talk" with this OBD 1 1|2 system.

Thanks
Joel
joeld is offline   Reply With Quote
The Following User Says Thank You to joeld For This Useful Post:
CathedralCub (05-19-2016)
Old 05-14-2016, 01:57 PM   #7
Senior Member
True Car Nut
 
rjolly87's Avatar
 
Join Date: Jun 2003
Location: Las Cruces, NM
Posts: 6,857
Thanked 298 Times in 246 Posts
rjolly87 has a brilliant futurerjolly87 has a brilliant futurerjolly87 has a brilliant futurerjolly87 has a brilliant futurerjolly87 has a brilliant futurerjolly87 has a brilliant futurerjolly87 has a brilliant futurerjolly87 has a brilliant futurerjolly87 has a brilliant futurerjolly87 has a brilliant futurerjolly87 has a brilliant future
Default

When PCMs fail, they typically like to set a bunch of unrelated codes, sending you on a wild goose chase.

Are you able to see a rise in engine RPM while cranking on the tachometer (if so equipped) or realtime data on the scanner? I am wondering if there is an issue between the ICM and PCM.

Also look at coolant temp if you can according to the PCM. Although I would expect a coolant temp sensor failure to set a code...
rjolly87 is offline   Reply With Quote
The Following User Says Thank You to rjolly87 For This Useful Post:
joeld (05-15-2016)
Old 05-14-2016, 03:44 PM   #8
Member
Posts like a V-Tak
Thread Starter
 
Join Date: Oct 2010
Location: Georgia
Posts: 78
Thanked 15 Times in 14 Posts
joeld will become famous soon enough
Default

Car does not have a tach. Scanner shows coolant temp same as outside air which is about 80* today.
Scanner will not show correct RPM'* when cranking, stays on 1k?

Joel
joeld is offline   Reply With Quote
Old 05-14-2016, 04:05 PM   #9
Member
Posts like a V-Tak
Thread Starter
 
Join Date: Oct 2010
Location: Georgia
Posts: 78
Thanked 15 Times in 14 Posts
joeld will become famous soon enough
Default

I just finished this check procedure: got to page 3, step 6. And the answer is NO. Light did not flash.

So, looking more and more like a bad PCM?


Joel

http://ww2.justanswer.com/uploads/JH...9_203717_2.pdf
joeld is offline   Reply With Quote
The Following User Says Thank You to joeld For This Useful Post:
CathedralCub (05-19-2016)
Old 05-14-2016, 10:19 PM   #10
Senior Member

True Car Nut
 
WilliamE's Avatar
 
Join Date: Jun 2011
Location: VA
Posts: 3,087
Thanked 418 Times in 376 Posts
WilliamE has a reputation beyond reputeWilliamE has a reputation beyond reputeWilliamE has a reputation beyond reputeWilliamE has a reputation beyond reputeWilliamE has a reputation beyond reputeWilliamE has a reputation beyond reputeWilliamE has a reputation beyond reputeWilliamE has a reputation beyond reputeWilliamE has a reputation beyond reputeWilliamE has a reputation beyond reputeWilliamE has a reputation beyond repute
Default

Sounds like bad PCM, or a problem with the injector circuit, I have heard of the injector circuit failing before.
WilliamE is offline   Reply With Quote
The Following User Says Thank You to WilliamE For This Useful Post:
CathedralCub (05-19-2016)
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
No spark/no injector pulse Mark Berry Buick 2 04-22-2014 03:53 PM
Torque converter clutch pulse solenoid larryam1 Buick 1 10-24-2012 12:06 PM
91 Riv, no spark, no inj pulse ToddC Buick 5 09-12-2011 09:02 PM
LN3 miss...pulse maybe2fast 1987-1991 14 04-24-2006 01:07 AM
Strange acceleration pulse Allmachtige 1992-1999 2 08-03-2003 03:09 AM


Thread Tools Search this Thread
Search this Thread:

Advanced Search

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
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -4. The time now is 12:15 PM.


We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.