Pennock's Fiero Forum
  Technical Discussion & Questions
  Pickup Coil vs. Ignition Control Module (ICM), trouble shooting 2.8L (no spark)

Post New Topic  Post A Reply
Email This Page to Someone! | Printable Version


next newest topic | next oldest topic
Pickup Coil vs. Ignition Control Module (ICM), trouble shooting 2.8L (no spark) by hdryder
Started on: 08-19-2014 05:44 PM
Replies: 17 (2597 views)
Last post by: Bebop on 10-04-2014 09:44 PM
hdryder
Member
Posts: 669
From: Virginia Beach, VA, USA
Registered: Apr 2011


Feedback score: N/A
Leave feedback

Rate this member

Report this Post08-19-2014 05:44 PM Click Here to See the Profile for hdryderClick Here to Email hdryderSend a Private Message to hdryderEdit/Delete MessageReply w/QuoteDirect Link to This Post
Is there a way to determine if either the Pickup Coil or the Ignition Control Module (ICM) may be causing a 'no spark' issue?

My '88 GT was running fine up until a few days ago. Then it began to start hard, and once it started, the tach jumped around until it warmed up.
Then yesterday on the way home from work, I stopped at the grocery store. When I tried to start it to get home, it would not fire up. The starter was turning over the engine fine.
I was just about ready to get some help from home, when it finally started. It ran ok on the way home, but would not re-start once I got it home.

I pulled the DuraLast cap and rotor off and returned them to AutoZone for new ones under warranty. I installed the new cap and rotor expecting it to start up.
It would not start up. I did a spark check, and I see now I am not getting spark at the plugs.

I believe some AutoZones are able to bench test an ICM if I bring it in loose off the distributor. So that is what I will probably do next.

Is there a way to determine if the Pickup Coil has failed?

I guess it may even be the Ignition Coil. I probably have a spare I can swap out for that.

Thank you for the help on this.

[This message has been edited by hdryder (edited 08-19-2014).]

IP: Logged
PFF
System Bot
tshark
Member
Posts: 4374
From:
Registered: Feb 2014


Feedback score:    (6)
Leave feedback





Total ratings: 64
Rate this member

Report this Post08-19-2014 06:12 PM Click Here to See the Profile for tsharkSend a Private Message to tsharkEdit/Delete MessageReply w/QuoteDirect Link to This Post
...

[This message has been edited by tshark (edited 09-08-2018).]

IP: Logged
85 SE VIN 9
Member
Posts: 690
From: Harwood Heights, IL, USA
Registered: Apr 2010


Feedback score: N/A
Leave feedback

Rate this member

Report this Post08-19-2014 06:27 PM Click Here to See the Profile for 85 SE VIN 9Click Here to Email 85 SE VIN 9Send a Private Message to 85 SE VIN 9Edit/Delete MessageReply w/QuoteDirect Link to This Post
O'Reilly's can also test the ICM and they offer a lifetime guarantee on their new ones. My money would be on the ICM. It was very convenient of it to fail at home. Not a bad idea to test the new one while you're at the store.
IP: Logged
hdryder
Member
Posts: 669
From: Virginia Beach, VA, USA
Registered: Apr 2011


Feedback score: N/A
Leave feedback

Rate this member

Report this Post08-19-2014 08:09 PM Click Here to See the Profile for hdryderClick Here to Email hdryderSend a Private Message to hdryderEdit/Delete MessageReply w/QuoteDirect Link to This Post
I just took two ICMs up to AutoZone for a test on their Wells machine. The ICM taken off the '88 GT 'failed', and second I had on a spare distributor 'passed'.
So I installed the ICM that 'passed' on the '88 GT, but the engine did not fire.
I did notice that the tach did not move during cranking.
I can't remember if that is normal or not.
IP: Logged
Bloozberry
Member
Posts: 7760
From:
Registered: Jan 2009


Feedback score: N/A
Leave feedback





Total ratings: 307
Rate this member

Report this Post08-19-2014 08:54 PM Click Here to See the Profile for BloozberrySend a Private Message to BloozberryEdit/Delete MessageReply w/QuoteDirect Link to This Post
The tach should read about 400 RPM while cranking so you're still not getting a spark. I'd try swapping out the coil with your spare one.
IP: Logged
85 SE VIN 9
Member
Posts: 690
From: Harwood Heights, IL, USA
Registered: Apr 2010


Feedback score: N/A
Leave feedback

Rate this member

Report this Post08-20-2014 06:41 PM Click Here to See the Profile for 85 SE VIN 9Click Here to Email 85 SE VIN 9Send a Private Message to 85 SE VIN 9Edit/Delete MessageReply w/QuoteDirect Link to This Post
Also check the connectors and the condition of the wires. Brittle and broken wires in the area of the coil are not unusual and can create strange problems.
IP: Logged
hdryder
Member
Posts: 669
From: Virginia Beach, VA, USA
Registered: Apr 2011


Feedback score: N/A
Leave feedback

Rate this member

Report this Post08-21-2014 10:17 AM Click Here to See the Profile for hdryderClick Here to Email hdryderSend a Private Message to hdryderEdit/Delete MessageReply w/QuoteDirect Link to This Post
Yesterday I swapped out the Ignition Coil, the small wire harness between Ignition Coil and Ignition Control Module (ICM), and the Electronic Control Module (ECM) from my '87 GT parts car.
Still no spark.
I have the spare distributor also from the '87 GT parts car, which appears to be a newer aftermarket unit. I will swap that out next.
Also, I will go through all the fuses.

Thank you for the help and ideas.
IP: Logged
TXGOOD
Member
Posts: 5303
From: Austin, Texas
Registered: Feb 2006


Feedback score:    (58)
Leave feedback





Total ratings: 87
Rate this member

Report this Post08-21-2014 12:28 PM Click Here to See the Profile for TXGOODClick Here to visit TXGOOD's HomePageSend a Private Message to TXGOODEdit/Delete MessageReply w/QuoteDirect Link to This Post
Make sure the connection between the pick-up coil and the ICM is good.
I had that happen on my 88GT and it turned out that the plug wasn`t connected good.
For some reason the plug on some pick-up coils and the little spade connector on some ICM`s are different shapes and they don`t always hook together good.
IP: Logged
Bloozberry
Member
Posts: 7760
From:
Registered: Jan 2009


Feedback score: N/A
Leave feedback





Total ratings: 307
Rate this member

Report this Post08-21-2014 05:42 PM Click Here to See the Profile for BloozberrySend a Private Message to BloozberryEdit/Delete MessageReply w/QuoteDirect Link to This Post
Also, make sure your distributor pick up coil looks like this (a little rust is OK...)



And not like this:

IP: Logged
f85gtron
Member
Posts: 657
From: Augusta, Ga. USA
Registered: Jul 2013


Feedback score: (3)
Leave feedback

Rate this member

Report this Post08-21-2014 06:48 PM Click Here to See the Profile for f85gtronSend a Private Message to f85gtronEdit/Delete MessageReply w/QuoteDirect Link to This Post
Check your pickup coil with an ohmeter and make sure you have some resistance. Also, check from the coil to ground to make sure it's not grounding to the distributor shaft.
Coil is easy to replace.
IP: Logged
84fiero123
Member
Posts: 29950
From: farmington, maine usa
Registered: Oct 2004


Feedback score: N/A
Leave feedback





Total ratings: 325
Rate this member

Report this Post08-21-2014 08:11 PM Click Here to See the Profile for 84fiero123Click Here to Email 84fiero123Send a Private Message to 84fiero123Edit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Bloozberry:

Also, make sure your distributor pick up coil looks like this (a little rust is OK...)



And not like this:



I've had a pickup coil that looked better than that first one fail, when ever the humidity was high and especially when it was raining the car would run like crap. test it, always test a part before replacing them, it can get very costly just throwing parts at a problem.

 
quote
Originally posted by f85gtron:

Check your pickup coil with an ohmeter and make sure you have some resistance. Also, check from the coil to ground to make sure it's not grounding to the distributor shaft.
Coil is easy to replace.


with what he said /|\

Steve

------------------
Technology is great when it works,
and one big pain in the ass when it doesn't



Detroit iron rules all the rest are just toys.

[This message has been edited by 84fiero123 (edited 08-22-2014).]

IP: Logged
PFF
System Bot
fffttt1
Member
Posts: 657
From: Granbury, TX.
Registered: Jun 2004


Feedback score: (2)
Leave feedback

Rate this member

Report this Post08-21-2014 09:46 PM Click Here to See the Profile for fffttt1Click Here to Email fffttt1Send a Private Message to fffttt1Edit/Delete MessageReply w/QuoteDirect Link to This Post
Just went through this on my '87 GT 2.8. Couple months ago cruising @ 75 the motor just shut off. Pulled over and replaced the ICM with the spare I carry (thanks guys on this forum :-) Car started right up and all was well. About 3 wks ago pulled in garage after work and shut off car. Next morning car wouldn't start. Changed ICM with new spare, no start. Did some testing, changed out for new coil - no start, more testing, pulled distributor and replaced pickup coil. Car started right up, but didn't mark rotor position prior to pulling distributor so timing was retarded. Pulled distributor and moved one tooth to advance timing. All is well. Don't be afraid of pulling distributor for this repair. But DO read the manual for the marking of the distributor and disassembly of the shaft components.
IP: Logged
phonedawgz
Member
Posts: 17009
From: Green Bay, WI USA
Registered: Dec 2009


Feedback score:    (23)
Leave feedback





Total ratings: 290
Rate this member

Report this Post08-22-2014 01:00 AM Click Here to See the Profile for phonedawgzClick Here to visit phonedawgz's HomePageClick Here to Email phonedawgzSend a Private Message to phonedawgzEdit/Delete MessageReply w/QuoteDirect Link to This Post
Before pulling the dist - Plug everything into your spare and attach a ground wire to it. Key on rotate the dist by hand and see if you get a spark. Then figure out which components work and which don't
IP: Logged
plane
Member
Posts: 41
From: UT
Registered: Oct 2011


Feedback score: N/A
Leave feedback

Rate this member

Report this Post08-22-2014 02:19 AM Click Here to See the Profile for planeClick Here to Email planeSend a Private Message to planeEdit/Delete MessageReply w/QuoteDirect Link to This Post
ICM is cheap and easy. If that doesn't work it is almost always the distributor and we always seem to want to change that last. I went through everything but the distributor and should have done that first. Even if you mark it, the new one is likely to have different timing/position form the old. My new one was a good 20 degrees different so took a long time to get it timed to even start - also doubted it was the dist for a long time), but I knew I was getting spark and some combustion so persisted.
IP: Logged
hdryder
Member
Posts: 669
From: Virginia Beach, VA, USA
Registered: Apr 2011


Feedback score: N/A
Leave feedback

Rate this member

Report this Post08-22-2014 06:25 AM Click Here to See the Profile for hdryderClick Here to Email hdryderSend a Private Message to hdryderEdit/Delete MessageReply w/QuoteDirect Link to This Post
I found this posted earlier by PFF member fierosound. It looks a good step-by-step testing procedure for the ignition system and module.

http://easyautodiagnostics....-mounted-icm-tests-1

Thank you for all the help.
IP: Logged
hdryder
Member
Posts: 669
From: Virginia Beach, VA, USA
Registered: Apr 2011


Feedback score: N/A
Leave feedback

Rate this member

Report this Post08-23-2014 11:31 AM Click Here to See the Profile for hdryderClick Here to Email hdryderSend a Private Message to hdryderEdit/Delete MessageReply w/QuoteDirect Link to This Post
I found the problem that was causing the no-spark issue on the red '88 GT solid roof car.
On the connector for the Pickup Coil to the Ignition Control Module (ICM), the white female connector had pushed back so far into the plastic connector, that it was not making contact with the male connector of the ICM.

Once I pushed that female connector back into place in the plastic connector, and seeing that it was making complete contact with the plugged in ICM, it started right up with the good ICM off my '87 GT parts car, that had passed with the Wells tester at AutoZone earlier in the week.

Thanks again for the help.
IP: Logged
Patrick
Member
Posts: 30124
From: Vancouver, British Columbia, Canada
Registered: Apr 99


Feedback score: (1)
Leave feedback





Total ratings: 442
Rate this member

Report this Post08-23-2014 02:52 PM Click Here to See the Profile for PatrickClick Here to Email PatrickSend a Private Message to PatrickEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by hdryder:

On the connector for the Pickup Coil to the Ignition Control Module (ICM), the white female connector had pushed back so far into the plastic connector, that it was not making contact with the male connector of the ICM.


I suspect it's often "simple" things like this which cause issues that are never properly diagnosed. Thanks for reporting what you found.
IP: Logged
Bebop
Junior Member
Posts: 5
From: Medford Oregon
Registered: Feb 2014


Feedback score: N/A
Leave feedback

Rate this member

Report this Post10-04-2014 09:44 PM Click Here to See the Profile for BebopClick Here to Email BebopSend a Private Message to BebopEdit/Delete MessageReply w/QuoteDirect Link to This Post
I had this same problem today. was driving along and all of a suddon BAM nothing. Had to be towed. Came here and found this topic. This place rocks. went to the store and bought one and wow!! its a whole diff car. The power had been not what I thot is should be and it ran rough. All that is gone now.
IP: Logged

next newest topic | next oldest topic

All times are ET (US)

Post New Topic  Post A Reply
Hop to:

Contact Us | Back To Main Page

Advertizing on PFF | Fiero Parts Vendors
PFF Merchandise | Fiero Gallery | Ogre's Cave
Real-Time Chat | Fiero Related Auctions on eBay



Copyright (c) 1999, C. Pennock