TPIGroove Posted January 28, 2023 Share Posted January 28, 2023 Hello all. I have a 1988 year model that has a little over 107,000 miles on it. Recently I noticed a slight ticking noise coming from the engine under certain conditions, although I'm not completely sure what the cause could be. Anytime the engine is revved up to maybe around 1900-2000 RPM or higher I'll barely hear the ticking noise, either on the highway or while pulling away from a stop. On top of that I'll sometimes notice it slightly when idling while the engine warms up from a cold start, although it's intermittent then. Is it possible the timing chain could be going out, or are there other things I should be looking at first? This vehicle is my daily for the time being (until I get my other car in working order), and I hate adding miles to it, but I do want to keep it running until it can get a full restoration. Link to comment Share on other sites More sharing options...
Ronnie Posted January 28, 2023 Share Posted January 28, 2023 It's hard to say what the ticking might be without hearing it. I doubt it is a timing chain at only 107k on it. I would take the belt off and see if the ticking noise goes away. That will tell you if it's something external to the engine, alternator, belt, pulley, etc. causing the tick. 1 Link to comment Share on other sites More sharing options...
2seater Posted January 28, 2023 Share Posted January 28, 2023 If it is a sort of knocking sound, primarily at idle speed, the harmonic balancer may be starting to fail, not an uncommon occurrence. Removing the belt will give a hint of that as well. Link to comment Share on other sites More sharing options...
TPIGroove Posted January 28, 2023 Topic Author Share Posted January 28, 2023 Did a quick diagnostic now that I had a chance to look further into it. Listening more closely it's not really a ticking noise, I don't think the valves are having any issue and there's no rattling in the engine bay. I'd say it's a little more accurate to say the engine sounds "tinny" when trying to accelerate. Usually anytime the engine gets in the mid 1700s the sound starts up, becoming more pronounced as I go to higher RPM. While I was driving home yesterday I was going up a hill, and tried to downshift for a bit more pulling power, but the car instead stumbled and slowed down even further despite the RPM increase. I talked to my mechanic, and he's assuming either a fueling issue or a clogged up catalytic converter. Is there a good way to check the fuel pump and flow before assuming it's the cat? I recently had an alternator issue that I had to swap out, but I'm not sure if a combination of the cold weather and the poor power delivery from the dying battery/alternator combo might have affected the pump or not. Link to comment Share on other sites More sharing options...
Ronnie Posted January 28, 2023 Share Posted January 28, 2023 Fuel problems usually don't cause a "tinny" sound. Here is a link to testing the fuel pump. It covers about everything your mechanic will need to know about fuel pump performance. Fuel Pressure Testing If the battery and alternator are good enough to start the engine, they won't cause a performance problem once it is running. With the relatively low mileage of your car, the cat isn't likely to be the problem. Poor performance (stumbling) when the engine is under a load is more likely to be a problem with the ignition system. Bad spark plugs/wires or the Ignition control module (ICM) most often the cause. 1 Link to comment Share on other sites More sharing options...
Padgett Posted January 28, 2023 Share Posted January 28, 2023 Also sounds more like detonation, can sound tinny and usually occurs under load. Link to comment Share on other sites More sharing options...
TPIGroove Posted January 28, 2023 Topic Author Share Posted January 28, 2023 Sparkplugs and wires were replaced recently, but is there a good way to confirm it's the ICM? I didn't see any goo leaking from it. Link to comment Share on other sites More sharing options...
Padgett Posted January 28, 2023 Share Posted January 28, 2023 I'd find a Delco unit and swap it. See here. Link to comment Share on other sites More sharing options...
Ron Walker Posted January 29, 2023 Share Posted January 29, 2023 Have you checked to see if you are getting any codes? I've had problems with poor performance and it was the ICM. I cut and pasted a reply from a previous post I made some months ago. The MAF was replaced (due to code (E034) and then I got a code for the Cam Sensor (E041). Replaced both which were of no help. I then got a code for the Ignition System (E042) and after checking and finding that two cylinders were not getting spark, I then replaced the Ignition coil and ignition control module. The car now runs great (at least for the 25-30 miles that I've driven since). Turns out, I suspect, that the ICM was probably the original culprit all along in spite of the E034 and E041 codes. Funny thing is that the codes popped up one at a time and not all at once. Had the E042 code shown up first, a replacement ICM and coil pack may have cured the poor performance right off the bat. As it is, I spent way too much on trouble shooting, especially with the replacement MAF (and also the catalytic converter) before checking the ignition coils. I'd suggest that anyone encountering extremely poor performance start off by testing the ignition coil and ICM. 1 Link to comment Share on other sites More sharing options...
Padgett Posted January 29, 2023 Share Posted January 29, 2023 BTW a secondary ignition (coils, wires, plugs) issue does not se a code. Link to comment Share on other sites More sharing options...
TPIGroove Posted January 29, 2023 Topic Author Share Posted January 29, 2023 The check engine light hasn't come on, but I can do a check for codes real quick. I'm gonna head to a junkyard and hope that there's still a car there that would have it, stuff from the 90's isn't that common anymore. Link to comment Share on other sites More sharing options...
2seater Posted January 29, 2023 Share Posted January 29, 2023 (edited) 1 hour ago, TPIGroove said: The check engine light hasn't come on, but I can do a check for codes real quick. I'm gonna head to a junkyard and hope that there's still a car there that would have it, stuff from the 90's isn't that common anymore. Pretty certain the ICM and coils up through the early 2000's will work. The catalog lists the Regal for instance uses the same ICM 1990-2004 Edited January 29, 2023 by 2seater Link to comment Share on other sites More sharing options...
TPIGroove Posted January 29, 2023 Topic Author Share Posted January 29, 2023 Does the order of the coils matter on an acdelco compared to the Magnavox? Link to comment Share on other sites More sharing options...
2seater Posted January 29, 2023 Share Posted January 29, 2023 49 minutes ago, TPIGroove said: Does the order of the coils matter on an acdelco compared to the Magnavox? I am not quite sure about what is being asked, but the location of the spark plug cables is the same relative to the firing order. The Delco style has both plug wires on one side of the coil vs alternate sides on the Magnavox brick, but the plug wires are paired the same. Starting from the end opposite the harness connector, the plugs are paired 6-3, 5-2 and 4-1, no matter if you have three Delco coils all marked 4-1 for example. It does not matter which side of the individual coils the wires are connected to, as long as the correct order of the pairs is maintained. Link to comment Share on other sites More sharing options...
TPIGroove Posted January 29, 2023 Topic Author Share Posted January 29, 2023 Guess I'll find out if this fixes it later, the mounting bracket doesn't match and the junkyard closed at 4. Link to comment Share on other sites More sharing options...
TPIGroove Posted January 30, 2023 Topic Author Share Posted January 30, 2023 2 hours ago, 2seater said: I am not quite sure about what is being asked, but the location of the spark plug cables is the same relative to the firing order. The Delco style has both plug wires on one side of the coil vs alternate sides on the Magnavox brick, but the plug wires are paired the same. Starting from the end opposite the harness connector, the plugs are paired 6-3, 5-2 and 4-1, no matter if you have three Delco coils all marked 4-1 for example. It does not matter which side of the individual coils the wires are connected to, as long as the correct order of the pairs is maintained. Now that I'm out of the 20 degree weather and cutting my hands up in a junkyard, I'll elaborate. The Magnavox layout on my car, top-down (towards connector) is 4-1, 2-5, 6-3. However, in the guide posted earlier I noticed on the AC Delco that the 4-1 coil is at the bottom, and the 6-3 at the top. Also I was able to source a mounting bracket from O'Reilly, so I can just wait for that to come in. Fortunately they don't close just as I get off work. Link to comment Share on other sites More sharing options...
2seater Posted January 30, 2023 Share Posted January 30, 2023 The Magnavox layout as stated sounds like it is backwards. 6-3 should be opposite end from the harness connection but I cannot confirm absolutely as my car is in storage 50 miles away. I do have a couple of coilpacks in a drawer but they can be installed backwards on the ICM, so hopefully someone will chime in with confirmation. Is it possible the actual plug wire connection does not match the number on the coil?? #3 would be easy to trace to which end of the coil pack it is connected. Link to comment Share on other sites More sharing options...
2seater Posted January 30, 2023 Share Posted January 30, 2023 This is a typical image of the firing order and coil pack arrangement for a 1988 3800. It is viewed from the rear but the relative locations are correct. Link to comment Share on other sites More sharing options...
TPIGroove Posted January 30, 2023 Topic Author Share Posted January 30, 2023 Here's a quick and dirty of the Magnavox, with 6-3 at the bottom where the harness plugs in. Is the AC Delco set up diffently? Link to comment Share on other sites More sharing options...
Ronnie Posted January 30, 2023 Share Posted January 30, 2023 2 hours ago, TPIGroove said: Here's a quick and dirty of the Magnavox, with 6-3 at the bottom where the harness plugs in. Is the AC Delco set up diffently? As you can see in your photo, the wire numbers are stamped next to where the plug wire connects. It appears your coil pack has been installed on the ICM 180 degrees from what it should be making number 6-3 nearest to the harness connector. I didn't know that was possible but apparently it is. If you reverse the coil pack numbers 6-3 will be on the opposite end from the harness connector as they should be. Below is a photo of my old Magnavox ignition with the coil pack installed properly. Numbers 6-3 should be on the opposite end from the from the harness connector on the Delco coils also. 1 Link to comment Share on other sites More sharing options...
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