Kevindjac Posted January 13, 2022 Topic Author Share Posted January 13, 2022 (edited) I misunderstood you @2seater but yeah guess you didn't see that the air comes through the vents on bi level, on all other settings at the floor and the defrost of course. Edited January 13, 2022 by Kevindjac 1 Link to comment Share on other sites More sharing options...
Kevindjac Posted January 13, 2022 Topic Author Share Posted January 13, 2022 @2seater I looked at the shop receipt when I replaced the plugs and wires,and the ICM and the coil was replaced also after I replaced plugs and wires, the other day I cleaned the IAC and it was lil sooty, and cosmetically there was some discoloration on the point of it. So I think next I think you said to check the plugs iirc. Link to comment Share on other sites More sharing options...
Kevindjac Posted January 13, 2022 Topic Author Share Posted January 13, 2022 @Ronnie so not sure if you saw my other post but air comes through the vents on bi level and at the floor on the other settings and of course defrost. So I decided to move on with the idling issue, so I've cleaned the IAC and was ok til the motor warms up then starts shaking about 45-50 mph still. Link to comment Share on other sites More sharing options...
Ronnie Posted January 13, 2022 Share Posted January 13, 2022 21 minutes ago, Kevindjac said: So I decided to move on with the idling issue, so I've cleaned the IAC and was ok til the motor warms up then starts shaking about 45-50 mph still. I apologize in advance because I sometimes get confused easily. It seems like you are talking about two different engine problems at once. You said you have an idling issue so you cleaned the IAC which would effect the idle. Did that make the engine idle smoothly? Then you go on to say the motor starts shaking at 45-50 miles per hour. Although it is possible something is causing a poor idle as well as the shaking I'm pretty certain it's not the IAC. As I said in a previous post, my experience has been that the ignition system is the first place to look when you have the engine missing (shaking) at low RPM and under a load. About 45-50 MPH is when the torque converter locks up and the transmission shifts to fourth about the same time. When that happens it puts more load on the engine and lowers the RPMs a lot. The next time the engine shaking starts at that speed, keep the same pressure on the accelerator pedal with your right foot and touch the brake pedal with your left foot. Just press the brake pedal down enough to cause the torque converter to unlock but not enough to apply the brakes. You should see the RPM go up when the torque converter unlocks. See if doing that causes the shaking to stop. If the shaking stops it is a pretty good indication that the ignition system is causing the engine shaking. 1 Link to comment Share on other sites More sharing options...
Kevindjac Posted January 14, 2022 Topic Author Share Posted January 14, 2022 Yeah @Ronnie sorry to confuse you, so yeah it seems like it's idling fine, but like I said about 45-50 mph the motor starts shaking I will try what you said to do, also I have replaced the ICM and the coil less than 2 years ago about same time the plugs and wires were also, I'm leaning towards just replacing the plugs again to see if that takes care of it, I did install cheap plugs so maybe they are just bad already IDK but after everything else it's the least expensive to do now! Link to comment Share on other sites More sharing options...
2seater Posted January 14, 2022 Share Posted January 14, 2022 If it has the Magnavox ignition, the original single coil block style, try closing up the spark plug gap to something in the .042"-.048" range. If it is a misfire under load, that may help. Incidentally, I just run Autolite copper core plugs, my preferred type from way back, but then again, I actually change whole engines somewhat regularly🙄 2 Link to comment Share on other sites More sharing options...
Kevindjac Posted January 20, 2022 Topic Author Share Posted January 20, 2022 Not sure what was init before it was replaced, I just know the ICM and the coil was replaced, but I will try the gap trick, I'll keep you posted it's cold here right now, so hopefully this weekend if it warms up! Link to comment Share on other sites More sharing options...
Kevindjac Posted January 23, 2022 Topic Author Share Posted January 23, 2022 @2seater so today I was getting ready to pull the plugs and the the first boot I pulled off the metal contact inside the boot stayed on the plug, looked like the wire was ripped off the contact,so I'm going to get some new plug wires try next weekend if I get a chance or weekend after I'll keep you posted. 1 Link to comment Share on other sites More sharing options...
Padgett Posted January 24, 2022 Share Posted January 24, 2022 8mm are best particularly with Delco ignition and .060" gap. Bright yellow iF available. Link to comment Share on other sites More sharing options...
Kevindjac Posted January 31, 2022 Topic Author Share Posted January 31, 2022 @2seaterso attempted to pull plugs this weekend got 2 out adjusted the gap like you said, 2 of them I broke the insulators on them so I'm just going to replace them all now, so my question is the new ones I put in should I gap those at .042"-.048" or gap them at the spec of .060"? Link to comment Share on other sites More sharing options...
2seater Posted January 31, 2022 Share Posted January 31, 2022 I know it is not a fun project to get at the rear plugs but I only suggested closing up the gap as an experiment to see if it improved the assumed misfire under low rpm and high load. It sounds like there may have been some other items in less than pristine condition as well. All new components should work with the .060" gap, but closing it up a little lessens the load on a Magnavox style ignition. .042" is probably a little tighter than needed but .045-.048" will help reliability without giving up too much ability to fire lean mixtures. 1 Link to comment Share on other sites More sharing options...
Kevindjac Posted February 19, 2022 Topic Author Share Posted February 19, 2022 So I replaced Plugs and wires and still at about 47 -50 mph, the motor shakes, so if any of you all can tell me what's my next part to replace I suspect the ICM and the coil, but @2seateror @Ronnie have any other Ideas to check first I'm open! TIA. Link to comment Share on other sites More sharing options...
rogold Posted February 19, 2022 Share Posted February 19, 2022 Since you have checked most of the common issues have you checked the engine or transmission mounts, or maybe a tire out of balance or bulged on the front of the car. Just thinking outside the box. Link to comment Share on other sites More sharing options...
2seater Posted February 19, 2022 Share Posted February 19, 2022 I was of the impression the ICM and coil pack were replaced? It is possible to get a bad part if they were. Link to comment Share on other sites More sharing options...
Kevindjac Posted February 23, 2022 Topic Author Share Posted February 23, 2022 (edited) Yes @2seater correct but most of stuff I read up on the ICM going out it works or it doesn't meaning it just doesn't gradually go bad! @rogold@2seater IDK maybe it's just slowly going bad not sure, but once it warms up I'll crawl under and see about motor mounts and tranny mounts! Edited February 23, 2022 by Kevindjac Wrong word Link to comment Share on other sites More sharing options...
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