: Studdering problem at low speed?



jwolf1010
07-06-09, 11:02 PM
While driving at around 20 mph in my neighborhood I felt like the engine was studdering. However I do notice that the V is running sluggish since filling her up today. I recently changed the plugs on Friday and everything seemed ok since then. I was running low on fuel and stopped at a gas station that was not of a known name brand. I used 93 Octane. Would the plugs cause this and if they were installed improperly would I receive a check engine light? If the fuel was actually not 93 Octane could this be the cause? If bad fuel will it hurt the motor? Thanks for the advice.

Florian
07-07-09, 09:38 AM
talk faster, that should cure it.


F

CIWS
07-07-09, 10:34 AM
The owner's manual says to run at least 91 octane in the engine. If for one reason or another you got bad gas and it's less than this, yes it's possible to hurt the engine. Once again the manual says you can run lower octane in "emergency" situations but to NOT run the car in WOT (wide open throttle). So if you suspect the gas I would keep the throttle down until you can get that gas out of there or run enough out to find some good 93 octane to fill it back up with to try and counter the bad stuff.

WillySTS
07-07-09, 10:45 AM
While driving at around 20 mph in my neighborhood I felt like the engine was studdering. However I do notice that the V is running sluggish since filling her up today. I recently changed the plugs on Friday and everything seemed ok since then. I was running low on fuel and stopped at a gas station that was not of a known name brand. I used 93 Octane. Would the plugs cause this and if they were installed improperly would I receive a check engine light? If the fuel was actually not 93 Octane could this be the cause? If bad fuel will it hurt the motor? Thanks for the advice.

BAD GAS, that is, gas with something in it other than gas can hurt your fuel system,ie;pump,filter and/or injectors, and/or you engine if it has diesel or kerosene or something like that in it. Water in gasoline(the most common thing in bad gas) usually just clogs injecotrs.

Just curious, though,...why would you be changing your spark plugs? They seldom cause a problem these days and really do last a very long time. I could see it, though, if you changed the TYPE of plugs, such as those ones you can get from D3...just wondering...:hmm:

jwolf1010
07-07-09, 11:03 AM
I like the talk faster comment. I used 93 Octane when I filled her up it just was at a no name brand type of gas station. As far as changing the plugs I read the forum and read everyones comments and their experiences and rely on you guys who have a lot more experience with modding cars than I do. I replaced the plugs on Friday and had no issues at that time.If it was the plugs would I get a check engine light? Would adding some fuel injector cleaner help?

CIWS
07-07-09, 11:12 AM
I used 93 Octane when I filled her up it just was at a no name brand type of gas station.

You put gas in the car that came from a pump marked as 93 octane. That's truly all you (or any of us) know without testing it.

jwolf1010
07-07-09, 11:25 AM
That's correct. It seems that after I filled her up I noticed the difference. The name of the gas station was U Gas here in Florida. We have no idea the true octane that we are really getting but I would hope to believe that I would have a better chance with a Chevron or Mobil. Any fuel injector cleaner that you guys would recommend or just baby it until I need fuel.Would there have been an immediate difference if it were the plugs?

Bee iLL
07-07-09, 12:53 PM
You could always try some octane booster if you really feel the 93 octane pump was not spewing 93 octane gas. I also don't see why trying fuel injector cleaner would hurt anything. You might just find out neither does anything to correct your problem and are simply out of $10-20.

inurok
07-13-09, 01:35 AM
I would not use octane boost in a supercharged vehicle. I made that mistake with my supercharged truck and fouled all the plugs? I dont know why I am not a mechanic just going by what they told me.

octane boost only boosts octane by like .25 fyi. I purposely stay away from no name gas stations with my supercharged and turbo vehicles.

CadV
07-19-09, 10:47 PM
If your running a K&N filter clean your MAF. Mine got messed up and was causing studdering.

Check the tension on your SC belt as well.

Here is a post I just made...

http://www.cadillacforums.com/forums/cadillac-cts-v-series-forum-2009/173651-dyno-results.html#post1944554