So sick of aftermarket parts

[austinado16]

Been having a little issue with the engine dying randomly, then not restart, and then for no apparent reason, it'll fire back up and run perfect, and not die again for days, or maybe weeks, or even months.

The 'burb isn't our DD, so duplicating the situation with enough regularity that it would fail permanently, or at least long enough to diagnose, was proving impossible...or at least difficult.

A respected GM trained tech friend of mine, who has his own independent GM shop recently told me that the most common cause was the ICM (igntiion control module) under the distributor cap. Well, about 18mos ago, I replaced the entire distributor with a "rebuilt" from NAPA. So last week I installed a new AC-Delco ICM.

A few days later, I noticed a lot of chattering from the recently replaced "NAPA" PCV valve. Actually, it'd been doing it for a while, and I kept forgetting to deal with it. A quick Google search showed that aftermarket PCV's were the cause, so I installed a new AC-Delco version. The chattering was gone and the idle improved....go figure.

Thought I had it all dialed in last week and we were leaving on Friday afternoon to drive 3hrs towing the camper w/ 5-6 of our daughter's cross country teammates on board.

Well, Friday afternoon I fire it up and it's developed a terrible stumble and misfire at idle, with the tach jumping around, and acting like it's going to die. It's too late to work on it, and it clears up after a minute, so off we go. It ran fine, but continued with the weid hot start stumble all weekend.

During the 3hr drive home yesterday, it died on the freeway at 65mph. Just simply shut down. As I moved the shifter toward neutral it fired back up and ran fine again.....wtf? About an hour later it died on the freeway again, and wouldn't restart at all. Coasted to the shoulder, popped the hood, disconnected the tach, wiggled the connectors for the coil and distributor, and it fired right up and got us home. It died again, while backing the camper into the driveway, and that was it; would not restart. Had the wife crank it over while I confirmed that it had good injector spray pulsing.........

......And now the rest of the story. About 3yrs ago I installed an MSD coil because the original coil was so loose in the bracket that it rattled. I'd saved that original coil and always kept it in the glove box. With the recent history of crap aftermarket parts, I was pretty sure that MSD had failed. I popped on the original coil and not only did the engine fire up and run perfect, it's not run so smooth in so long I can't remember. Gone is the cold idle miss. Gone is the occasional hot idle miss.

Needless to say, I'll be permanently remounting the original coil after I pour JBWeld in around so it no longer rattles.

 

[Jims86]

Been having a little issue with the engine dying randomly, then not restart, and then for no apparent reason, it'll fire back up and run perfect, and not die again for days, or maybe weeks, or even months.

The 'burb isn't our DD, so duplicating the situation with enough regularity that it would fail permanently, or at least long enough to diagnose, was proving impossible...or at least difficult.

A respected GM trained tech friend of mine, who has his own independent GM shop recently told me that the most common cause was the ICM (igntiion control module) under the distributor cap. Well, about 18mos ago, I replaced the entire distributor with a "rebuilt" from NAPA. So last week I installed a new AC-Delco ICM.

A few days later, I noticed a lot of chattering from the recently replaced "NAPA" PCV valve. Actually, it'd been doing it for a while, and I kept forgetting to deal with it. A quick Google search showed that aftermarket PCV's were the cause, so I installed a new AC-Delco version. The chattering was gone and the idle improved....go figure.

Thought I had it all dialed in last week and we were leaving on Friday afternoon to drive 3hrs towing the camper w/ 5-6 of our daughter's cross country teammates on board.

Well, Friday afternoon I fire it up and it's developed a terrible stumble and misfire at idle, with the tach jumping around, and acting like it's going to die. It's too late to work on it, and it clears up after a minute, so off we go. It ran fine, but continued with the weid hot start stumble all weekend.

During the 3hr drive home yesterday, it died on the freeway at 65mph. Just simply shut down. As I moved the shifter toward neutral it fired back up and ran fine again.....wtf? About an hour later it died on the freeway again, and wouldn't restart at all. Coasted to the shoulder, popped the hood, disconnected the tach, wiggled the connectors for the coil and distributor, and it fired right up and got us home. It died again, while backing the camper into the driveway, and that was it; would not restart. Had the wife crank it over while I confirmed that it had good injector spray pulsing.........

......And now the rest of the story. About 3yrs ago I installed an MSD coil because the original coil was so loose in the bracket that it rattled. I'd saved that original coil and always kept it in the glove box. With the recent history of crap aftermarket parts, I was pretty sure that MSD had failed. I popped on the original coil and not only did the engine fire up and run perfect, it's not run so smooth in so long I can't remember. Gone is the cold idle miss. Gone is the occasional hot idle miss.

Needless to say, I'll be permanently remounting the original coil after I pour JBWeld in around so it no longer rattles.

Good deal, but I thought after you had been a member here this long, you would have changed back to the original coil within a few days....glad you kept it in the glove box. Aftermarket ignition parts, shoul come with trunk lid/tailgate warmers.

 

[89Suburban]

Wise words spoken guys. That is my plan when replacing any parts on this motor in the future. I started yesterday with new AC Delco plugs.

 

[austinado16]

As a long time German car tech, I'm a hardcore believer in only using OE and OEM parts. To the point of; I refuse to use anything else unless it's from a tried and true German company.

I let down my guard on the 'burb thinking that I could get some sort of good quality "American" parts via NAPA. I also thought that MSD had enough of a reputation that coil as basic and normal as one for a small block would be trustworthy.

Kicking my own ass for being a douche. Not to mention, being the guy hauling other people's kids in old-school iron, and then breaking down.

Good news is, all the **** parts have been removed and it's running better than it has in years.

 

[dhamp]

Glad you got the problem fixed. I don't know if you'd been posting on here about the ongoing issue or not. If so, I'd been missing them. If I'd seen 'em and know about the MSD install, I would have suggested exactly what you did. I had a car in college that I decided to put an "upgraded" Accel coil in when I was doing my routine tune-up because the car had been having a very slight miss at idle since the previous tune-up. I started having the same issue. I'd be driving and the damn thing would just cut off. 75% of the time it would crank right back up. Other times, I'd wait 30 minutes to a few hours, and then it would start up. After many hours spent eliminating my security and sound systems, I remembered I changed that stupid coil. Took it back as a warranty item and got standard AM replacement. Problem was gone immediately.

 

[austinado16]

I'd only posted about the weird dying last week, or maybe the week before, but hadn't mentioned the MSD coil. I'm not used to seeing coils fail. It's so rare on the German stuff that I've worked on, that I can almost say it "never" happens. When I have seen a coil fail, it's been in a way where it wouldn't produce spark under load. So the engine would run fine unless you were trying to accelerate while driving. I've never seen a coil just shut down, and/or be fine a few minutes later........other than magneto type ignition coils as are used in stuff like lawn mower/power equipment engines.

We took the 'burb out yesterday and ran it around town for about 2hrs running errands. It's back to normal, except that it's back to having a slight miss once fully warmed up/hot. From a cold start yesterday, it was fantastic and smooth, and even the idle was basically just a smooth small block "hum." About 900ish in neutral, and 600ish in gear. And smooth, like you had to listen for it to be running, you couldn't feel it.

But once it got good and hot (by hot I mean; everything up to operating temps) after 30-45min or so, it was back to a much lower idle out of gear, and in the 550ish range in gear, with a noticeable random miss that we could feel in the seats.

It's been like this for a long time, and I've never found any sort of intake manifold leak, and a new EGR valve didn't help either. It did it with the original manifold, and still does it with the Edelbrock installed. Definitely feels like a lean miss.

I've never worked on the throttle body at all, or done a test of the fuel pressure. I've also never put an oxygen sensor in it, or unplugged the 02 sensor to see if the idle changed. I've also not replaced the coolant temp sensor for the ECM, or the idle air control valve. I did take the valve out last week, and was surprised that it looked pretty good. Question: how does the IAC work? Does it move inward and outward like a plunger, or does it rotate in and out, like a screw? With it removed should I be able to work the end pin in and out like a plunger (I couldn't) or spin it like a screw (I couldn't).

 

[hootsmcgoots]

Sounds eerily similar to what I have been experiencing. New Accel dist, plugs and wires.

I will just die out of nowhere, no specific situation that caused it making it hard to trouble shoot/diagnose. Sometimes it will immediately fire back up, sometimes it takes a few minutes, but always eventually starts back like nothing was wrong.

There was a faint smell of fuel everytime it stalled so i assumed there was a carb problem. Took off the airhorn, adjusted floats, cleaned needles and seats, screens, cleaned the bowls. Idled just fine. got 100 ft out of the parking lot at work and it died. Then died 4 more times within the nex 1/4 mile. Got it fired up the last time, and cruised the next 10 miles the whole way home.

I'll be looking into this tomorrow....

 

[austinado16]

For future reference, bring a can of starting fluid with you. When it dies, give it a blast of starting fluid. If it fires right up, that indicates it wasn't getting fuel, and your starting fluid provide "fuel." If it doesn't fire up, you know you have a spark issue. At least with that quick test, you can get pointed in the right direction.

I'd suggest picking up a spare coil and spare ignition control module, either new ACDelco stuff, or hit the local wrecking yard and see what you can find. Ebay is a good source too. I just purchased a new ACDelco coil for $20 (and a new ignition key lock assembly with GM keys for similar money).

Been driving the 'burb locally all week, including one 60mi round trip on a really hot day. It's been perfect. The old coil is mounted back in the bracket. I put the new ignition in today.

Waiting on the parts to rebuild the throttle body, but that's another story. No real issues with it, but with 283k on the clock, it's long past due and I want to be able to set the fuel pressure and know it's correct.

 

[hootsmcgoots]

Found the culprit in big white letters

You must be registered for see images attach

Quit for good yesterday. Put in the new coil, I could start it but still a little choppy. Installed a new icm and idles smooth as silk at 600 rpms.

 

[Chaz]

I had an msd coil on when I first got my truck,,,ran good at times and ran like crap at others,,,,took me forever to diagnose what the hell was wrong until Jim told me to chuck the msd coil,,,,what a pos that coil is,,,,your post reminds me my PCV valve rattles like hell also,,,and now that I think of it I bought it from Oreilllys, aftermarket part, its getting chucked tomorrow,,,,,


c

 

[austinado16]

@hoots......That's fantastic that the coil and ICM got you back running smooth again. But what a PIA to have to go through all that.

@chaz.........yes, that new ACDelco PCV will cure the problem. Get a new grommet at the same time if yours is baked hard (mine was).

My new coil arrived today, so that's in the glovebox as a spare, along with a spare ICM. Next on the purchase list is a IAC (idle air control valve), but so far, I'm not seeing any in ACDelco so I'll probably have to go with Airtex-Wells.

Drove the 'burb 3-1/2hrs each way on the freeway, to a Cross Country meet today. It ran flawless whether holding down the slow lane at 55 with the cruise control on, or blasting along with traffic at 70-75 w/ both air conditioners running. Hated to burn that kind of fuel, when the Rabbit Diesel Pickup would normally have been my tool of choice, but I needed to make sure the 'burb was solid. I can't have a hauler that's got the potential to us stranded several hours from home.

No parts for the TBI rebuild yet from CFM. They're starting to piss me off. I'm guessing they charged me for "real" shipping, and then sent it all parcel post in order to pocket a buck. Nice goin'.

 

[89Suburban]

Found the culprit in big white letters

You must be registered for see images attach

Quit for good yesterday. Put in the new coil, I could start it but still a little choppy. Installed a new icm and idles smooth as silk at 600 rpms.

Great job figuring it out

 

[89Suburban]

@hoots......That's fantastic that the coil and ICM got you back running smooth again. But what a PIA to have to go through all that.

@chaz.........yes, that new ACDelco PCV will cure the problem. Get a new grommet at the same time if yours is baked hard (mine was).

My new coil arrived today, so that's in the glovebox as a spare, along with a spare ICM. Next on the purchase list is a IAC (idle air control valve), but so far, I'm not seeing any in ACDelco so I'll probably have to go with Airtex-Wells.

Drove the 'burb 3-1/2hrs each way on the freeway, to a Cross Country meet today. It ran flawless whether holding down the slow lane at 55 with the cruise control on, or blasting along with traffic at 70-75 w/ both air conditioners running. Hated to burn that kind of fuel, when the Rabbit Diesel Pickup would normally have been my tool of choice, but I needed to make sure the 'burb was solid. I can't have a hauler that's got the potential to us stranded several hours from home.

No parts for the TBI rebuild yet from CFM. They're starting to piss me off. I'm guessing they charged me for "real" shipping, and then sent it all parcel post in order to pocket a buck. Nice goin'.

How about the valve cover grommet for the breather tube, you replace that?

 

[austinado16]

Good idea to replace it too. But it's not on the "intake" side of things so if it's leaking air, it's not causing a lean run condition..........the PCV valve is the control for that crankcase vapor "leak" into the manifold.

 

[89Suburban]

Good idea to replace it too. But it's not on the "intake" side of things so if it's leaking air, it's not causing a lean run condition..........the PCV valve is the control for that crankcase vapor "leak" into the manifold.

I'm just wondering if you ever replaced yours that's all. They seem to harden up and shrink and oil starts to wet the cover. I'm going to shop around for one.