Results 1 to 3 of 3
Thread: Need help with P0300 misfire
-
10-23-2005, 05:27 PM #1
- Join Date
- Aug 2005
- Location
- Newport, Mi.
- Posts
- 116
red- 1999 Camaro SS
Need help with P0300 misfire
In coming home two weeks ago (200 mile trip),, the SES light come on and the engine started to run a little rough.
I limped the car home and check for DTC codes. I had multiple misfires and mainly on #3. The misfire history on #3 was in the many thousands.
I pulled some plugs and found that they were very sootie black. Pull one O2 and it was in bad shape, also. The LFTFs were +25%. I judged that the O2 were reading lean when it really was not. I had turned the PCM to -5% LTFT in most FTCs. So I figured that if I installed new front O2 sensors and all new plugs, clear the DTC codes, the engine would be back all good with no misfires.
But that did not happen, I still had a noticable miss, as well as, ATAP telling me random misfires on #3.
So I swapped #1 coil with #3, cleared codes, no change, still have misfire #3.
Now, I swapped #1 plug wire for #3 plug wire, cleared codes, still #3 misfires.
So whats going on??? Can the PCM identify the wrong cylinder? maybe its a misfire on #6 for example.
In addition, some searching turned up a CKP Learn procedure, what is this thing?
-
10-23-2005, 08:21 PM #2
might be a bad injector...is it leaking fuel?
-
10-24-2005, 07:05 AM #3
- Join Date
- Aug 2005
- Location
- Newport, Mi.
- Posts
- 116
red- 1999 Camaro SS
I'll have to check the fuel pressure drop off at key off. But I am thinking that for the LTFTs to go to +25%, the PCM must have detected a lean condition in order to increase the LTFTs to max. Therefore, a clogged injector might do this.
Thread Information
Users Browsing this Thread
There are currently 1 users browsing this thread. (0 members and 1 guests)
Similar Threads
-
P0300 misfire code...help:(
By Lotapwr in forum General HelpReplies: 7Last Post: 05-02-2013, 07:19 PM -
P0300 code random misfire...
By MagicMan in forum General HelpReplies: 87Last Post: 07-31-2009, 01:27 PM -
P0300 Random Misfire #2 and #7
By skyking in forum Internal EngineReplies: 8Last Post: 07-10-2007, 09:03 AM -
*HELP* P0300 Multi Misfire
By shwagg in forum Firebird / WS6Replies: 7Last Post: 08-09-2006, 07:51 PM -
*HELP* P0300 Multi Misfire
By shwagg in forum General HelpReplies: 4Last Post: 08-02-2006, 05:03 AM
Bookmarks