Engine pings under load going up steep grades at various speeds. Have been using 87 octane on a regular basis - pun intended - switching to higher octane doesn't seem to make any difference. Changing the air filter and plugs. What else should I be looking at? Coil rail system thus no distributor or coil to mess with. I believe that the timing is controlled by the PCM. Will I need to have the timing checked/reset at the dealership? Thanks.
Steve
Try running can of SeaFoam through a vacuum line to clean the upper engine of carbon and perhaps another full can into the gas tank to clean the injectors.
If you haven't done a tune-up in the past 2 years/24k you are overdue for service. Do the SeaFoam before replacing the spark plugs and use the 'old fashioned' copper plugs, they seem to do better in Jeep engines than the new high-tech ones in many cases..
I have run the 20 oz size of Techron through the tank and didn't notice any improvement. Engine has 127K on it BTW. What else is there to do for a tune-up? No distributor, rotor, points, condenser, coil to change out. Fuel filter is in the tank. What am I missing? Thanks again.
Steve
billy ray wrote:
Spark plugs, ALL the fluids and ALL the lubricants, clean the throttle body and idle air passages, ALL new filters.
Your owners manual has a schedule of service, follow the "Severe Service" recommendations, use ONLY the correct fluids, not what you see advertised and good quality filters.
For example: Nothing made by Prestone meets current or past DC specs, Fram oil filters meet ONLY the minimum specifications but sell at a premium price.
Also... Techron makes two formulations. Techron Cleaner which is the concentrated stuff and Cleaner with Techron which is the diluted stuff.
If you are having drivability problems it wouldn't hurt to do the fuel system cleaning twice.
Switch to a major brand fuel, the premium for their stronger cleaners, that should knock off the carbon deposits, that's pre igniting your rot sh*t now, then drop to that station's 87 no alcohol if you can find it. God Bless America, Bill 0|||||||0 mailto: snipped-for-privacy@aol.com
Merrill
I use Wix oil filters and Castrol dino 10W-30 every 3K
Steve
It has been widely reported and I got first hand experience last summer with a serious drain back issue on the Fram filters.
I had just finished a hard 3000 mile run in my CJ7 so I changed the oil out and bought the 'on sale' filter at the local auto place.
Well, I started having bad starts with a 'lot' of valve lifter noise so I thought I wore out the old engine until I read a thread on the Fram and remembered I had on in now.
I changed the filter and all the bad start up noises went away.
As far as the 'ping' goes, have you checked the clutch on the rad fan if it has one? When they wear out, they make some strange clicks and noises.
Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's Canadian Off Road Trips Photos: Non members can still view! Jan/06
I got that "bad start" problem with a Fram filter once. I figure once is too much.
Earle
Thanks Steve and Mike
I guess I am getting lazy, and the Fram with the texture is easy to remove by hand. My inventory of both thread filters is almost depleted so I will replace with a better quality filter. Yes, I do get a little lifter noise.
And yes, my fan clutch needs to be replaced although it doesn't make weird noises yet. I just don't need a fan that runs at full speed at
-30.
Merrill
The pinging noise my fan clutch started to make before it started shaking the front end half off the road was it (the fan) taking little pieces out of the shroud. The strange front end vibration I also had went away after the fan took the shroud right out in pieces so I realized it was causing all the trouble...
Mike
merrill wrote:
Long overdue follow up. I turns out the check engine light did come on with a "P0302 Cylinder #2 Misfire". Pulled out the Bosch platinums that someone else had installed and put in the Champions. That solved the problem. A little puzzled that the plug didn't look bad.
Steve
billy ray wrote:
How long have you run the new Champions? Please let us know if it recurs.
tw
Steve Landis wrote:
About a week, took me awhile to get to this. Back to 87 octane no pings. Question: the Champions came gapped at .50 but engine sticker spec'd .35 I re-gapped to .35 Have heard .50 is correct but followed the spec in the engine compartment. What's the wisdom here?
Thanks Steve
twaldr> How long have you run the new Champions? Please let us know if it recurs. >
The 35 is correct. It makes it start easier when cold and run smoother.
It is really odd that Bosch plugs don't work in a lot of Jeep engines. When they come to me with a miss, first thing I check is the plugs. Toss the Bosch and everything is good again.
Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail > About a week, took me awhile to get to this. Back to 87 octane no pings.Go with the spec'd .35
tw
Steve Landis wrote:
That is puzzling. I've had good luck with them in Porsches. I don't know if we will ever get a decisive answer to why that happens in Jeeps. It's not the first incident I've heard of.
tw
If it was just the 4.0 I'd be thinking it's heat related since cyl 6 doesn't get as much cooling as the rest. It's got to be a hotspot problem of some sort. I tried plats in my zj and it pinged from the first test run. Took them back. Now I just use Autolite. Champion works also, but I'm not impressed as they look sorta cheap.
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