help!!!!! service engine soon
Thread Starter
Instructor
Joined: Sep 2006
Posts: 157
Likes: 1
From: Tampa FL
help!!!!! service engine soon
i read some past threads about some people setting timing higher than stock for better all around perf, smoother idle and better gas economy. so i tried it for extra hp and tq as some say. some people hear set it at 8 and some set it at 10 or higher.
well i did notice imediately is the car felt a lot faster when you accelerate to pass someone esp. in low gear. it also idles higher like at 800 in P or N. and yeah i set my timing at 10 to be safe.
now when im cruising steady at 55, car feels like its bucking back and forth and chugging like im off the gas for a split second and got back on it. service engine soon light comes on for like 10 seconds and turned off.
kinda scared me a little because i thought it stalled. then it drives again just fine again steady cruising at 50. it started to chug back and forth again at that speed and the service engine soon light comes again for about 10 sec then turns off.
seems to me like a very slight missfire but i dunno if it really is. when it idles in gear its feels like its randomly missfiring. idle in P or N the car feels like its shaking. i get on it from a stoplight and the car still acelerates just fine and still feels much faster than before. the only problem is when its crusing at a steady speed.
any ideas?
well i did notice imediately is the car felt a lot faster when you accelerate to pass someone esp. in low gear. it also idles higher like at 800 in P or N. and yeah i set my timing at 10 to be safe.
now when im cruising steady at 55, car feels like its bucking back and forth and chugging like im off the gas for a split second and got back on it. service engine soon light comes on for like 10 seconds and turned off.
kinda scared me a little because i thought it stalled. then it drives again just fine again steady cruising at 50. it started to chug back and forth again at that speed and the service engine soon light comes again for about 10 sec then turns off.
seems to me like a very slight missfire but i dunno if it really is. when it idles in gear its feels like its randomly missfiring. idle in P or N the car feels like its shaking. i get on it from a stoplight and the car still acelerates just fine and still feels much faster than before. the only problem is when its crusing at a steady speed.
any ideas?
Race Director
Joined: Oct 2005
Posts: 11,776
Likes: 182
From: Rolla Missouri
2021 C4 of the Year - Unmodified Finalist
St. Jude Donor '10 thru '25
yeah, set the timing back where it's supposed to be. 
Unless you have the mods that require timing to be different, your car will run best with the factory setting.
If more advance improved all around performance, smoother idle and better fuel economy, then I think it would have been set there from the factory.
Unless you have the mods that require timing to be different, your car will run best with the factory setting.
If more advance improved all around performance, smoother idle and better fuel economy, then I think it would have been set there from the factory.
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
I had been running 8deg BTDC and recently bumped it to 12deg BTDC for a little harder launch at the strip.
I do run a 160deg T-stat & fan sw, an AFPR with higher than stock pressure and only run premium fuel.
To see if the miss at idle is caused by some electrical issue in turn clip a timing light onto each plug wire. If you see missed flashes coincide with engine miss then you have isolated the plug or wire that is the issue.
I do run a 160deg T-stat & fan sw, an AFPR with higher than stock pressure and only run premium fuel.
To see if the miss at idle is caused by some electrical issue in turn clip a timing light onto each plug wire. If you see missed flashes coincide with engine miss then you have isolated the plug or wire that is the issue.
Thread Starter
Instructor
Joined: Sep 2006
Posts: 157
Likes: 1
From: Tampa FL
i have a code 33 high voltage maf circuit and code 44 lean exhaust. how can this result in extra timing? put the timing back to stock drove to work and had no prblems. no misfire and the ses light never came back on. 
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
I could see maybe the lean exh due to more complete charge burn and not enough fuel but the MAF code is a puzzle.
I agree, clear the codes, see if they come back with stock timing; then bump base timing and see if it throws the codes again.
I agree, clear the codes, see if they come back with stock timing; then bump base timing and see if it throws the codes again.
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