GM Forum - Buick, Cadillac, Olds, GMC & Pontiac chat

GM Forum - Buick, Cadillac, Olds, GMC & Pontiac chat (https://www.gmforum.com/)
-   Buick (https://www.gmforum.com/buick-172/)
-   -   Hard start cold Fixed! Changed coil (https://www.gmforum.com/buick-172/hard-start-cold-fixed-changed-coil-227541/)

bill buttermore 01-04-2006 10:36 PM

Hard start cold Fixed! Changed coil
 
3 Attachment(s)
Working on my neighbor's '90 LeSabre. It has the Series I (square) coils.

It has been very hard to start in the cold. Once running, works fine. Starts OK warm. Has stalled a couple of times recently.

My first effort was to remove the throttle body to inspect the AIC pintle and passages. Throttle body was black with soot, no oil. Cleaned it and the MAF, and checked the resistances on the AIC. All OK.

Hard start cold persisted.

Checked coil resistances and got:

6-3........14.5 K ohm

Attachment 70871

2-5.........12.4 K ohm

Attachment 70872

4-1.........open

Attachment 70873

Obviously I've got a bad coil. Can I swap in a series II ICM and coil pack? Will it just bolt and plug in? Or do I need to do something else?

Are those symptoms consistent with a bad coil? Once it starts, it runs normally without any apparent misfiring.

willwren 01-05-2006 09:42 AM

You've got a funny intermittent or high resistance that breaks down under load, allowing current flow.

A Megohmmeter would probably read that open coil fine, but most people can't find those any more.

I'm assuming it's the Magnavox setup? One solid coil with 6 posts and 3 humps? I'd do a Delco2 swap on it and call it good.

bill buttermore 01-05-2006 09:58 AM

Thanks, Bill. I'll pick up a SeriesII coil pack and ICM this AM at the junkyard and let you know how it goes.

Yeah, it has the Magnavox setup, I guess. Three humps on the same cast base. I used the multimeter I got for free with the Actron scan tool. Set it to the 200K ohm range for the readings. Measurements were made cold (30*F). I wonder if it is a break that touches and completes the circuit after it starts to run. That's how it's acting.

For others wanting to try this, I just found this post from jr's3800 searching "coil swap": (Who knew it would be that easy?)

http://www.bonnevilleclub.com/forum/...ight=coil+swap

BillBoost37 01-05-2006 10:20 AM

Bill...the only big thing you need to ensure it that you get the L27 mounting plate to ensure it bolts right up.

bill buttermore 01-05-2006 10:29 AM


Originally Posted by BillBoost37
Bill...the only big thing you need to ensure it that you get the L27 mounting plate to ensure it bolts right up.

So, there is a difference in the ICM mounting setup between the LN3 and the L27?

bill buttermore 01-05-2006 10:31 AM

I'll just pull the magnavox unit and take it with me to make sure the bolt holes line up with the new unit.

banned3800 01-05-2006 10:33 AM


Originally Posted by bill buttermore

Originally Posted by BillBoost37
Bill...the only big thing you need to ensure it that you get the L27 mounting plate to ensure it bolts right up.

So, there is a difference in the ICM mounting setup between the LN3 and the L27?

You need the plate that goes underneath the ICM from an L27... The series II engines have a diffrent mounting bracket altogether...

When you find the L27, that plate I'm talking about attaches to the bottom of the ICM via the coils, and that plate has 3 bolts in it in the exact same arrangement as the Magnavox module..

Let me know and I can dig up some pics to show you what I'm talking about...

;)

__________________
Best Car Insurance | Auto Protection Today | FREE Trade-In Quote

bill buttermore 01-05-2006 10:39 AM

OK, I think I got it. I need a mounting plate from an L-27. I mount the ICM and coil pack from any Series II to that, then install in the LN3 (?)

banned3800 01-05-2006 10:40 AM


Originally Posted by bill buttermore
OK, I think I got it. I need a mounting plate from an L-27. I mount the ICM and coil pack from any Series II to that, then install in the LN3 (?)

Correct.... Dead on the money ;)

Make totally sure you get the coil bolts from the L27 as well... The series I and 2 use diffrent size bolts for the coils even tho the coils are almost identical..

L27 Coil Bolts
Lower ICM bracket with the lower bolts to attach to the alternator bracket

L36-67 series II
ICM
Coils

Hope that helps

__________________
Best Car Insurance | Auto Protection Today | FREE Trade-In Quote

bill buttermore 01-05-2006 11:35 AM


Originally Posted by jr's3800

Originally Posted by bill buttermore
OK, I think I got it. I need a mounting plate from an L-27. I mount the ICM and coil pack from any Series II to that, then install in the LN3 (?)

Correct.... Dead on the money ;)

Make totally sure you get the coil bolts from the L27 as well... The series I and 2 use diffrent size bolts for the coils even tho the coils are almost identical..

L27 Coil Bolts
Lower ICM bracket with the lower bolts to attach to the alternator bracket

L36-67 series II
ICM
Coils

Hope that helps

It do. Off to the junkyard!


All times are GMT -4. The time now is 08:27 PM.


© 2024 MH Sub I, LLC dba Internet Brands