question about missing
11-15-2008, 09:38 AM
#1
Thread Starter
Join Date: Nov 2008
Location: tennessee
Posts: 6
question about missing
I have a 04 mach1 and yesterday when I got in it I noticed it had a miss at idle and lower rpms. I ran two tanks of 87 octane in it but last night filled up with premium. the car jumps at a crusing speed of under 80 but if you get on it the car runs fine. kinda feels like your in to high of a gear and need to down shift. any suggestions or anyone had this problem with the fuel.
11-15-2008, 11:41 AM
#2
4th Gear Member
Join Date: Dec 2007
Location: Maryland
Posts: 1,503
Read the section of your manual regarding what type of fuel needed to run. Never run any fuel under 91 octane, and get accustomed to which station's gas is 92 and which is 93. There isn't a $ diff between the two, stick with 93. I can't tell you the 87 octane was the cause of the miss, but it I were a betting man I'd bet on it. The entire motor's set up is computer calibrated for premium gas. Fuel injectors can suffer with the improper octane, and one of the audible symptoms of that is a miss...hence the sound. Start with putting only 93 in it for a couple/few tanks, then work your way up from there.
11-15-2008, 02:06 PM
#7
4th Gear Member
Join Date: Dec 2007
Location: Maryland
Posts: 1,503
Okay take it easy on a brother! Yup, he should've known. I still talk to some, performance car owners included, who think the higher octane is "recommended" and don't realize that anything less will actually do damage. Don't put him down, help him. The lessons we learn with experience.
11-15-2008, 02:19 PM
#8
6th Gear Member
Join Date: Mar 2007
Location: Chicago, IL
Posts: 6,169
Okay take it easy on a brother! Yup, he should've known. I still talk to some, performance car owners included, who think the higher octane is "recommended" and don't realize that anything less will actually do damage. Don't put him down, help him. The lessons we learn with experience.
11-15-2008, 03:08 PM
#9
corner carver
Join Date: Oct 2006
Location: New England
Posts: 4,371
High compression or boost requires higher octane. My friend used to have a Turbo Saab. Nothing special performance wise but it still was pushing boost. He though that the "Recommended" meant that he only needed to use higher octane if he wanted more performance.
11-16-2008, 11:56 AM
#10
Thread Starter
Join Date: Nov 2008
Location: tennessee
Posts: 6
I only have had the car for a week and was only looking at the speedo not the writing around it. lol I am going to go ahead and change the plugs today and get a code reader. I had them run it last week and it was the o2 sensors but it came back on . Just wanting to make sure it dosent say anything else. It still bucks and jumps at a crusing speed but runs perfectly fine when you stomp it. knida like when you are just barely pressing the gas. I will let you know how it comes out. Thanks for the info.