I had just got off a long road trip car drove great everywhere. Well on my way to a freinds house I stopped to get gas. Probly 1 min after driving down the road the car starts studder bad. But if you give the car a little more than quarter throttle it drives fine. Driving the freeway is the worst . I can put it in cruise control and without skipping a beat about every 2 min it just shudders and drops to 1500 rpm and then picks back up. If i gun it like from a stop light it runs fine. Whats really wierd is after like 10 min of driving it like fixes itself for a little bit, but will go right back to it if i shut the car off then on. There is no knock in the idle. I'm not getting any Cel's from the trans or engine. But I mean could bad gas really cause this much? Here in Utah we are cheap and yes I put 85 octane in my car. But this has never happened before. I've never had a auto trans go bad on me before so i don't know what to look or feel for. Any help is greatly appreciated. thnx

 

I Believe Its The Gas I Have A Asc400 The Gas Attendant Put Regular In My Car Once It Started To Studder To But In The Same Case 2 Weeks Later My Tranny Went.

 

I'm thinking its the gas because 91 octane is recommended on these cars. Did you use 85 octance previously without issues?

 

yes, for the last month and a half I have without issues. i dunno i'm just gonna run the **** outta the car and see what happens. get the gas out asap. If I have to drive to vegas and back i will.

 

haha do it! drive to vegas, fill up the rest of the tank with 91 and run the tank empty.

my gf used to fill up with 87 in the LS400 and after a few weeks it started to shudder like crazy. i put a few tanks of 91 and it went back to normal. i don't want to imagine what 85 would do. use 91+ only, cost a few bucks more but it will save your engine.

 

i use 89 and over >.>

whenever i need maybe 1-2 gallons of gas to get to my destination i put 89.. but when i fill full tank i use 91 :]
no problems so far :]

 

did you guys know that there is only a $4 difference between filling our tanks (from bone dry to complete full, 20 gallons) between the cheap stuff and the good stuff... $4...

On a car that averages 25 mpg, and drives 12000 miles a year, the difference between regular and premium is $96 per year... With that, you get better gas mileage, better performance, and a car that just runs better overall...

Even if you only averaged 18 mpg and drove 15000 miles per year the difference is still only $166 / year...

Definitely worth it...

 

yeah whats really wierd is i've driven it to 3 destinations today, and it shudders for about 3-4 min and goes away. its really wierd. like its a fuel issue. usually i can tell if i have an exhaust if its detonating or so forth. stock exhaust, no idea. I will fill it with premium from now on.

 

Sounds like the tranny is going, going......

Hope I'm wrong for your sake.

 

the wierdest thing. the problem is completely gone. no sign of anything. my guess if i may have a lose wire going to the dizzy or maf. I'm gonna also jump my connector to look for any codes. keep yah updated

 

awww, me likey

 

The previous owner of my car ran 87 octane and it showed. The car only put down 152 whp stock on 87 (my friend's made just shy of 180 stock with an exhaust on 91). I run nothing but 91+ in mine.

 

My experience with fuel....

Ok so I was poor one day and had to put in 5 bucks of the cheap stuff (chevon) instead of premium to float through to payday. My car did NOT like that....it's started idling really crappy the day after. When payday came I filled up with the usual premium unleaded. I've always used premuim in mine and as far as I know the previous owners did to. I bought my 92 SC with 176k and it's always looked and run like new so I have to assume it's been well taken care of and I'm the 3rd owner of this particluar vehicle.

That 5 bucks worth of cheap gas ended up later costing me a tune-up but that's another thread..haha.