Idling Rough Lately

[CaptainXL]

Oil was low, put in a quart and a half today. About 7-8k miles on this oil change. Was going to go 10k miles on my first batch of mobil 1 extended performance with filter.

You might have an oil leak somewhere. Synthetic oil moves more easily past seals. Check all around and underneath the engine. Make sure the oil filter is correctly installed. Failing that I would make sure to flush the engine prior to changing the oil next time. You might be able to unstick some rings if that turns out to be the problem.

 

[jeffro312]

You might have an oil leak somewhere. Synthetic oil moves more easily past seals. Check all around and underneath the engine. Make sure the oil filter is correctly installed. Failing that I would make sure to flush the engine prior to changing the oil next time. You might be able to unstick some rings if that turns out to be the problem.

Can I ask quick question not trying to hijack maybe u can pm me. What's best method to flush engines

 

[TangoBravo]

You might have an oil leak somewhere. Synthetic oil moves more easily past seals. Check all around and underneath the engine. Make sure the oil filter is correctly installed. Failing that I would make sure to flush the engine prior to changing the oil next time. You might be able to unstick some rings if that turns out to be the problem.

Actually synthetic oil never really leaked past seals and easier then mineral, however when synthetics first came out they had a bad rapp because the seal swell formulas more closely matched that of euro cars, and time on the market showed that, that type formula didnt work well with american cars. It was changed and hasn't been an issue since for most every car out there now. As long as you're using the same viscosity you have always used then you should have no new seal leaks come up. Synthetic oil typically "burns" off slower then mineral oil so if you are experiancing major oil loss then you more then likely have an issue that I would address rather quickly. In all my years selling synthetic oil I can't remember a time when oil use didn't go down, unless of course there was an underlying issue like bad rings.

 

[CaptainXL]

Actually synthetic oil never really leaked past seals and easier then mineral

Sort of. Actually due to the uniform molecular formula synthetic oil has a propensity to dissolve deposits inside an engine more so than regular oil. If you start running it in an engine which originally was run with regular oil for a long time you can experience some additional leakage (assuming there were leaks) which would have been masked using regular oil. However according to Mobile 1 synthetic oil in itself will not cause any leaks if the engine has always used synthetic and/or had no leaks to begin with. My suspicion was that there was a leak to begin with in his case. The engine will need to be checked to verify this.

Can I ask quick question not trying to hijack maybe u can pm me. What's best method to flush engines

I would do a search under my name. have mentioned it a couple times in other threads.

 

[DenaliHD66]

Can I ask quick question not trying to hijack maybe u can pm me. What's best method to flush engines

Nah by all means go ahead and post the answer to this man's question. I'd like to know myself. Perhaps all those cans of seafoam over the last few years could have worn out my o-rings? This oil leak this is a brand new issue, but the misfiring started on this same oil change. At this point I just think the manifold needs taken apart and everything checked out. I'd like to do a restoration myself but its my main vehicle right now and just don't have the tools for that.

 

[CaptainXL]

Well basically this is what I do.

When the oil is ready to be changed and the engine is warmed up drain two quarts of oil to bring the level down to roughly 5 quarts level. Careful hot oil!

Then add two quarts of BG quick Clean BG Quick Clean for Engines | Oil Products | Automotive Products | BG PRODUCTS UK , CRC Fast Motor Flush 05336 -- Fast Motor Flush™ 5-Minute Engine Cleaner, 30 Fl Oz or equivalent. These are the more effective products but I find that Gunk engine flush is more readily available around me.

Follow directions on container and drain oil until it starts to drip at the drain plug hole. Install drain plug. Change oil filter. Fill with oil of your choice of the correct weight. 5W-30 happens to be the best weight that works for me and is what I recommend due to the fact that it provides better mileage and reaches engine parts quicker in cool climates.

Over the next few months monitor the color of the oil and note any drastic change in it's color. If the oil changes to black relatively soon then do another flush as before. For this reason I recommend that you use a cheap 5W-30 the first time you fill after flushing the engine the first time.

You can also go one step further and spray some carb cleaner down the spark plug holes and let it soak overnight.

Hope this helps.

 

[gmcman]

This oil leak this is a brand new issue, but the misfiring started on this same oil change.

What did you do at this change specifically to the engine? Did you seafoam on the plugs that are still in the motor? Reason I ask is back in the day I would hear that if you used seafoam or top engine cleaner, it was best to do this before a plug change as it could foul the plugs.

Once the smoke bomb cleared then you change the plugs and that was with the old-school plugs, these plugs are very temperamental as well as our ignition system.

Did you remove the coils yet and apply the grease? If not I would do this asap since another poster just recently burned up 3 of his coils and this was likely the culprit.

 

[mcc]

Oil was low, put in a quart and a half today. About 7-8k miles on this oil change. Was going to go 10k miles on my first batch of mobil 1 extended performance with filter.

That really does seem like a lot. To add another point of data: 3.7k miles after my last oil change, I had to add less than 1/4 of a quart to bring it back up to full. My I6 has ~109k miles on it and it's filled with Pennzoil Ultra. It saw only dino oil previous to the current change as far as I know.

I don't know if that's the norm, but it IS a data point from an engine with roughly the same # of miles on it.

 

[DenaliHD66]

What did you do at this change specifically to the engine? Did you seafoam on the plugs that are still in the motor? Reason I ask is back in the day I would hear that if you used seafoam or top engine cleaner, it was best to do this before a plug change as it could foul the plugs.

Once the smoke bomb cleared then you change the plugs and that was with the old-school plugs, these plugs are very temperamental as well as our ignition system.

Did you remove the coils yet and apply the grease? If not I would do this asap since another poster just recently burned up 3 of his coils and this was likely the culprit.

The current plugs, with ~9k miles on them, have had roughly 3 seafoam treatments. I shall apply the grease next day off. When I pull them out, I just apply the grease to the bottom of the spring inside the boot where it contacts the plug head?

That really does seem like a lot. To add another point of data: 3.7k miles after my last oil change, I had to add less than 1/4 of a quart to bring it back up to full. My I6 has ~109k miles on it and it's filled with Pennzoil Ultra. It saw only dino oil previous to the current change as far as I know.

I don't know if that's the norm, but it IS a data point from an engine with roughly the same # of miles on it.

Tell me about it, I pulled the dipstick out and only the bottom tip below the rough area had any oil on it. The engine was warm, not operating temperature too. Ran to store to get some more oil, came back and put it in a warm engine and checked again until full. I should check it tomorrow before I fire it up to see the cold level.

For the last 80k miles I've used Mobil 1 synthetic 5w30 with fram (cheap) oil filters. This one, Mobil 1 synthetic extended performance 5w30 with Mobil 1 performance filter. Can't imagine the viscosity of the oil changed that much, other than just being able to put some more miles on the oil before changing.

How would I be able to tell if my O-rings are bad? I just really don't think its an internal mechanical problem as opposed to electrical. The thing runs like a top and performance has NEVER suffered.

 

[gmcman]

The current plugs, with ~9k miles on them, have had roughly 3 seafoam treatments. I shall apply the grease next day off. When I pull them out, I just apply the grease to the bottom of the spring inside the boot where it contacts the plug head?

Well, IMO...I would pull a couple plugs and post their condition. I never really was a fan of the seafoam but some say it works well, I like to use BG44K at about 12-15K intervals or yearly. I think not having the grease may be the culprit.

As far as oil, I have been a big M1 user but switched to Valvoline at my last change. I changed at 8500 miles and over the time I almost went through a quart but I have a small leak at the valve cover in the front and rear, just enough to make a dirty spot but not running out. Over time I'm sure it can equal a quart and burn off unnoticed.

You may need new plugs but check them first, yes a good pea-sized amount or more at the tip of the spring coil.

 

[CaptainXL]

Dielectric grease is an insulator. All it does it ease in plug boot installation and keep moisture out of the coil to spark plug interface. I highly doubt adding the grease would make things better. I would be more concerned about the spring tension inside the boot.

 

[jeffro312]

Check plugs and boots for any sort of corrosion. Check spring tension.

Can maybe use something abrasive to clean end of plug and possibly do same inside of boot get a good connection surface and make sure u use grease. These of coarse are just cheap easy fixes that'd I'd try before spending money

If no luck replace spark plugs still no luck move boots around see if any symptom follows

Just keep working your way up the ladder till your able to pinpoint something


Or bring it to a mechanic and pay them to use there fancy "tools" to "diagnose" your problem and hope u can trust him

 

[gmcman]

This is the grease I am referring to.

Electrical System Maintenance : Permatex® Dielectric Tune-Up Grease

 

[gmcman]

Denali, any progress?

 

[DenaliHD66]

Its been running fine ever since, and haven't had a chance to get it scanned. I am close to just buying a ScangaugeII and Haynes manual so I can just start doing stuff myself.