Really need some sage advise/guidance on this particular issue....

Stats: 2006 H3 3.5L 84K miles
(girl friends) just bought 3+ weeks ago

We were on our way home and the truck started to loose power. It began to buck and stutter.
The CEL/MIL fired randomly and then went fully lit.

Coasting the truck it would be solid lit and then pulse when accelerating. There is seriously a bad shuttering and at 1/4 to 1/2 throttle it will drop to barely idle and come close to die'n....


We brought it home parked it in the driveway and ran diagnostics on it...(P0301 misfire cyc#1)
Note: She got gas last night on way home from work
Checked Oil (full and clean)
Checked Trans fluid (cleaned and topped off with Dexron VI)
Checked Antifreeze (cleaned and midway up overflow)


Took the air intake system off and the MAF, resonator assembly. (The TB,TBS, MAF and intake tubes were cleaned)

Disconected the Battery and removed 1st spark pack thru 5th...(Kept em in order they were taken out)
Removed the 1st spark plug and verified the spark plug had/has been firing (by color/look)
Went to Autozone and purchased all new spark plugs and a new COP for spark plug #1.
Replaced all sparks and COP #1
Recleaned MAF and installed all components as normal.
Reconnected battery.

Started engine and still surging, bucking and pulsating with reduced power. Engine is misfiring P0301.

Took MAF plug apart (i.e. weatherPac disassem.) cleaned with MAF spray and rebuilt.

Reconnected battery.

Started engine and still surging, bucking and pulsating with reduced power. Engine is misfiring P0301.

Truck ran fine all day till this issue began...

I'm wondering what would be the next logical step to take?

Chris

 

I would first try getting as much of that gas out with a pump. You can purchase a cheap manual one at parts store. Replace with fresh fuel and if that does not cure it and you still insist pursuing it yourself I would try one at a time replacing each coil pack with the one you just pulled out untill you hit the right one. Happened to mine and hit on the third try.Was not the cylinder my diagnostic tool said it was.Personally I would be back to whomever I bought it from. Any warranty?

 

Went back to square one.
*checked continuity in coil spark wire harness... ok
*pulled harness plugs at each coil / main contact connector for coil wires...
*removed fuse box cover blew out fuse with compressed air
*cleaned fuse 23 and reseated
*disconnected + - cables
*removed all coils and sprayed silicon in bases/reseated

Put everything back in place and pulled ECU out checked cables for tightness and dryness

Truck started and ran... ahh! PRICELESS!:-)
Took for test drive...
Chris

Not sure but it runs right now.

 

sounds like coil pack issues though

 

Sounds like old fuel or water in the fuel mix.

 

The major shuttering, stumbling and general crap running with serious misfire was tentatively smoothed to a stumble from time to time.


After much of Friday and part of Sat. was able to get my GF's '06 3.5l 84K engine to smooth out and run correctly. Thank GOD! Alas short lived. The newest symptoms seem to be a blip, stumble in the engine that happens when at idle. It is random and very short lived. It is usually a milli second blip and the engine never comes close to dying or loosing rpm's.


Things that have already been done:
Checked Oil (full and clean)
Checked Trans fluid (cleaned and topped off with Dexron VI)
Checked Antifreeze (cleaned and midway up overflow)
Took the air intake system off and the MAF, resonator assembly. (The TB,TBS, MAF and intake tubes were cleaned and then re-cleaned)


Disconnected the Battery and removed 1st spark pack thru 5th...(Randomized them)
Removed the 1st spark plug and verified the spark plug had/has been firing (by color/look)
Went to Autozone and purchased all new spark plugs and a new coil for spark plug #1.
Replaced all sparks and COP #1 .....ACDel 41-103....Wells COP
The oem that I removed were ACDel ...also but different #.
Re-cleaned MAF and installed all components as normal.
Took MAF plug apart (i.e. weatherPac disassem.) cleaned with MAF spray and rebuilt.
Techron 2- bottles added today 12-10-12..
Reconnected battery.
Where is a good place to look next for the sudden blip in the idle?


She is now talking about taking it in at $125 per hour just to resolve this small issue. Ugh!

Also sprayed silicone in each boot when re installing COP 1-5.
Chris

 

As you now describe it I'm 99% sure you have a bad coil pack/packs.You can try one by one till you hit the right cylinder or replace all of them at once.What you are now describing is identicle to what I experienced.Autozone (Duralst C1395 ignition coil) $72.95. My wife spent hundreds of dollars at two different garages to no avail till I had time to look at it. Been 6 mos now and purrs like it should. Because you changed cyl. #1 does not mean that was it.Could be you have another misfire or #1 was not the problem.The MIL light will not always come on in this situation.

 

Let me ask, does it still have the POS original battery terminals on it?

 

Well shes back driving Sugar baby this week.
Ended up replacing bat + & - con. & new bat.
Thank GOD! Jeezze....
Chris