Did the tune up, runs great for a week then.....

[wchain]

Hi Ladies and Gents,
Youll recall my earlier post here http://jeepkj.com/forums/viewtopic.php?p=36350&highlight=#36350

I replaced all the plugs with Champion Copper Plugs, Installed a new air cleaner, and a new battery, cleaned the throttle body with 3M Throttle body cleaner.

THis was last week. The jeep ran great the whole time until today. She calls and says the Check engine light came on as she picked up her daughter. When she came out and started it, the light was blinking. Any time she tried to go over 35, the truck would surge and buck.

She was less than half a mile from home, so I asked her to limp it there. I got my code scanner, and I got Codes:

P0300
P0305
P0306
P0355

I immediately pulled the #5 and #6 Coils and checked the plugs, to make sure the plugs were snug. The plugs were fine. I drove the truck and it was fine, next stop light, I accelerated, and it bucked when it got to 40 mph, so I pulled over, pulled the codes again and got the same set. I then selected the "Clear Codes" button, and drove the truck, which drove fine again, but the light was on, not blinking, but steady.

So here I am. Light is on, but truck drives fine, same codes present.

Anyone?
Thanks in advance guys and gals!!

 

[valvestem]

Bucking

I am thinking it is the "new" plugs that were used. The Libs are very sensitive to what plugs are used for OEM replacement.

 

[sprsonic]

02 liberty is notorious for weak or broken valve springs. i would recomend the cheapest route first, which would be to get a can or two of mopar combustion chamber cleaner, get the vehicle to operating temp and while engine is running, remove the intake maniold vacuum hose to brake booster and spray the whole can into the intake through this hose. when the can is empty turn vehicle off if it does'nt stall on you first.let engine sit w/cleaner in off position for 20-30 minutes. after that start and hold idle to 1800-2000 rpms till smoke is gone, the engine will run horrible and smoke like mad. dtc's will reset. take the vehicle out and give her hell. may take 1 or 2 times till repair is complete, "if its not valve springs." if you can catch valve spring replacment before they break, its a rather easy and inexpensive repair concidering you could have to replace an engine if a valve hits a piston. try this first and keep us informed.

 

[wchain]

Thanks for the replies guys.

The I thought OE recommended plugs are Champions?

THe truck still has the 7/70 so if it is broken valve springs, I will be taking it back.

FWIW at 37K the heater core burst and blew both the head gaskets and warped the heads. The dealer replaced the heater core, decked the heads and installed new head gaskets.

 

[2003KJ]

well it sounds like you already knew what the codes ment (300 is multiple cylinder misfire, 305 and 306 is cylinder 5 and 6 missfire(which makes sense that 300 came up too)), and 355 is Ignition Coil E Primary/Secondary Circuit Malfunction.

Somebody else on here last week posted about a problem and when I looked the code up it was an Ignition Coil issue...I believe theirs was an 05 too. Might do a quick search on that and see what you find.

 

[MoladoGuy]

If its still driving fine you may now just have to wait until the Check Engine Light goes away. This usually takes 3 good full drives.

I hope its nothing more than that. Good Luck.

 

[Mini Sumo]

This is exactly what my '02 has been doing ! I'm going to try the cleaner deal and see what happens. I've already been thru the replace the spark plugs and coils deal

Thanks for all the great info


Mini Sumo Was here

 

[merchjo]

I had the same thing done but by the dealer, was going on a trip and did not have time. Anyway on the way back the check engine light comes on and the engine is running rough. I took it in on Tue and get a call by the end of day that there was a miss fire in #1 #3 and #5 cylinder. Today they called and said the whole head needs to be replaced, soemthing to do with valves. Now my truck is a 2005 - is this a common problem on the liberty engine?

 

[JeepJeepster]

I had the same thing done but by the dealer, was going on a trip and did not have time. Anyway on the way back the check engine light comes on and the engine is running rough. I took it in on Tue and get a call by the end of day that there was a miss fire in #1 #3 and #5 cylinder. Today they called and said the whole head needs to be replaced, soemthing to do with valves. Now my truck is a 2005 - is this a common problem on the liberty engine?

Uhh.. Never heard of something like that on an 05? I figured they had used a different type of springs on some and thats why some people are have valve train problems.. Maybe its something other than bad valves? Ask them whats wrong with it? 8-[

 

[merchjo]

Idid ask, they said there is a problem with tthe head and valves and it was going to take till next week to get the parts and fixed. I need to take a ride up and talk to him directly.

 

[2003KJ]

Idid ask, they said there is a problem with tthe head and valves and it was going to take till next week to get the parts and fixed. I need to take a ride up and talk to him directly.

Something doesn't sound right here. Ask them EXACTLY what the issue is, and to be as detailed as possible.

 

[merchjo]

Went to the dealer today, he was busy but he did tell me there is a TSB that explains if you get the error codes I go to replace all the valves in the engine. I looked at the TSB and it does list the valves, seals, keepers and gaskets as well as time it takes. I forgot to write down the TSB but I figure there is enough guys around here that could get that info.

 

[JeepJeepster]

Went to the dealer today, he was busy but he did tell me there is a TSB that explains if you get the error codes I go to replace all the valves in the engine. I looked at the TSB and it does list the valves, seals, keepers and gaskets as well as time it takes. I forgot to write down the TSB but I figure there is enough guys around here that could get that info.

***** for chrysler!! No wonder they took the 7yr/70k miles warranty away! 8-[

 

[2003KJ]

wow, what years does this TSB cover?

 

[merchjo]

Not sure....

 

[merchjo]

Hey guys

Had my buddy who works for another Jeep dealer talk to their service manager. He confermed there is a TSB that if you get code P0300 and you know the plugs are good its a good chance you have the valve problem. Its usally affects the #3 cylinder but can affect others like mine. I will have the TSB and will post a copy tomorrow.

 

[merchjo]

Here is the TSB


http://home.comcast.net/~merchjo/jeep/jeeptsb-page-1.jpg

and
http://home.comcast.net/~merchjo/jeep/jeeptsb-page-2.jpg