Not using preimum gas

Sandmanownz

Registered User
I just got my SC this Sat and when i filled her up I used the 2nd grade, not unleaded but not preimum cause i wasent thinking about it. Last night when i was coming home the car started to die almost like it didnt have any gas. At idle it would drop rpm really bad and want to die.. Im assuming it is cause of the gas because of the fact that the light that points to the "Preimum Unleaded Fuel Only" was coming on. Now that i filled it up (it was almost on E) w/ premium gas it starting to smooth out again @ idle, is the reason for it going this the gas? I mean i dont see any other reason for it doing that. And will it smooth out and be ok?
 
87 or 89 octane fuel works fine at idle and part throttle, but it burns too quick under boost and will pre-ignite causing severe engine damage. I don't know of any light that indicates you have the wrong grade of fuel in the tank.

It probably something else or maybe you got a bad tank of gas...either way don't run anything less than 91 octane. If you must run lower octane, pull the octane plug...it will reduce ignition timing by 4 degrees to reduce the chances of detionation.

David
 
Well Dave, Its a light on the tac. it has an arrow pointed ethier to the "Premium Fuel Only" or the tac? All i know is thats its an arrow. I know my Cam Shaft Sensor is going bad, but i dont think that would do this would it? What it does is like, ill be going and then the check engine light will blink and make a noise, at the same time that arrow lights up and the whole car like almost loses power... drops a lot of rpms and makes it kind of jerk. At an idle it will idle really good then do that then go back to a good 700rpm or so idle... it was doing it a lot last night, but i filled it up w/ the premium like i said again, this morning i had it idle while i got ready for work, it died once during like the 15minutes or so it idle'd but it was doing it like once every 30sec last night. I'm leaning tword it being ethier a bad tank of gas like you said or.. Now that ive gave a little more detailed description do you have any other ideas? Any help is good help, thanks!
 
Sandmanownz said:
Well Dave, Its a light on the tac. it has an arrow pointed ethier to the "Premium Fuel Only" or the tac? All i know is thats its an arrow. I know my Cam Shaft Sensor is going bad, but i dont think that would do this would it? What it does is like, ill be going and then the check engine light will blink and make a noise, at the same time that arrow lights up and the whole car like almost loses power... drops a lot of rpms and makes it kind of jerk. At an idle it will idle really good then do that then go back to a good 700rpm or so idle... it was doing it a lot last night, but i filled it up w/ the premium like i said again, this morning i had it idle while i got ready for work, it died once during like the 15minutes or so it idle'd but it was doing it like once every 30sec last night. I'm leaning tword it being ethier a bad tank of gas like you said or.. Now that ive gave a little more detailed description do you have any other ideas? Any help is good help, thanks!

The upshift light is what you are seeing. The conditions you described are consistant with a bad crank sensor and/or harmonic balancer. It WILL leave you stranded at some point. Get it fixed ASAP. Both are common failures on SC's.
 
Sandmanownz said:
Would it do it really bad at one point, and then not do it as bad the next day?

Yes. It can also work perfectly one second and refuse to start or run the next. It often gives no warning and can shut off completely in the middle of traffic.
 
Ya i was driving and all of a sudden it started doing it, but this morning it only died once and then was running fine.. Last night it wouldnt even idle the rpm's would go crazy low and it would almost die then it would catch itself and go back up to idle and then go back and such. I guess it bigger than i thought, guess its time for my first repair?! hah anyway, does it sound like that is the problem? And do you know how much it might cost for parts? And I appriciate your help, both of you.
 
QUOTE:The upshift light is what you are seeing. The conditions you described are consistant with a bad crank sensor and/or harmonic balancer. It WILL leave you stranded at some point. Get it fixed ASAP. Both are common failures on SC's....
I would heed this advise and do a search on the crank sensor and HB. The search function is going to turn up a LOT of info on the subjects. Good luck, shouldn't be too bad.
Tom
 
Ya, I know the cam shaft sensor was going bad, I'll just have to replace crank sensor and such along with it, looked in other forum posts and thats exactly what its doing, i thank you guys for the help.
 
David Neibert said:
If you must run lower octane, pull the octane plug...it will reduce ignition timing by 4 degrees to reduce the chances of detionation.


Dave,

I haven't heard of this, what do you mean octane plug?

Michael
 
90blkbrd said:
Dave,

I haven't heard of this, what do you mean octane plug?

Michael

I think It's intended for when you can't get high octane gas. Just pull the gray plug.

octane.jpg


David
 
That sounds a lot like when my crank bolt broke. It acted up for a couple days then just quit completely. I never saw an upshift arrow; I'm not sure the late model has one.

It cost me about $500 with parts and labor, including removing the broken bolt. If you can get the bolt out before it breaks it would be cheaper. The parts you would need to do it yourself would be:

~$220 balancer from ford
$25 crankshaft sensor
~$5 bolt and washer

You can get a better BHJ balancer for more money, and I think there was a post a couple weeks ago with a possible source for a much cheaper stock balancer.
 
TBone95 said:
That sounds a lot like when my crank bolt broke. It acted up for a couple days then just quit completely. I never saw an upshift arrow; I'm not sure the late model has one.

It cost me about $500 with parts and labor, including removing the broken bolt. If you can get the bolt out before it breaks it would be cheaper. The parts you would need to do it yourself would be:

~$220 balancer from ford
$25 crankshaft sensor
~$5 bolt and washer

You can get a better BHJ balancer for more money, and I think there was a post a couple weeks ago with a possible source for a much cheaper stock balancer.


This is Mike (Sandmanownz) on Shockwave's computer, we are looking at it now. We've checked the HB, and the bolt is still solid and the HB runs true. He had his break in the past so we were looking at that. We are looking into it possibly being the DIS, the place i bought it from seems to have replaced it and possibly used to much compound on it, maybe not allowing it to be ground totally. Thats about as far as we have gotten so far... If its not that maybe look into the crank boly a little more.
 
Is it hard to start when it dies? One real good indication of the crank sensor is the constant cranking without starting.

The upshift light is what makes everyone think of the crank sensor, but I dont think that will throw a CE light. Id check the codes and see whats causing that before replacing anything.
 
Sounds like these guys got your problem diagnosed Sandman but on the fuel issue try if at all possible to use high octane. These are high compression engines. the lower your octane the lower compession level for detonation..thats bad.. you can bend valves, break pistons,or rods stuff like that. Good luck. Hope you enjoy your SC as much as I do mine.. ;)

Rick in FL :cool:
 
Sweet90SC said:
Sounds like these guys got your problem diagnosed Sandman but on the fuel issue try if at all possible to use high octane. These are high compression engines. the lower your octane the lower compession level for detonation..thats bad.. you can bend valves, break pistons,or rods stuff like that. Good luck. Hope you enjoy your SC as much as I do mine.. ;)

Rick in FL :cool:

He wont be using low octane gas anymore, even though it's unrelated to his problem.

When I drove the car the tach was perfect and the check engine light came on during driving, but would go out at idle. I ran codes for him and the only code that came up was 214 as a strored memory code. There were no engine running codes. The car always starts every time. When driving the car the check engine light would come on about as soon as you got over 25 mph. Somebody had messed with the DIS module recently, so we looked into that. I pulled the DIS and there was new greas applied and the edges were corroded. I cleaned up the mounting surface and DIS module and reapplied heat sink compund. Now for the first time since he has onwend the car (Saturday) the check engine light has been out. He drove the car last night for quite a while and had no problems or check engine light.

I will keep this thread updated on the situation.

Jerry
 
David Neibert said:
I think It's intended for when you can't get high octane gas. Just pull the gray plug.

octane.jpg


David
Ummm... Does that base look like this? :confused:
 

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TbirdSCFan said:
Ummm... Does that base look like this? :confused:

Dave Neibert is pointing to the octane plug.
TBirdSCFan thumbnail pics show the EGR Solenoid connector.

TBirdSCFan, since you have a 90 Auto you don't have the EGR. They didn't change the harness on those non-EGR cars. The octane plug looks just like the SPOUT jumper block on top of the A/C compressor.

Code 214 is back with engine stumble. He brought the car by, and I rechecked codes. It finally did stumble while I was able to see it for my self. The car was sitting at 700 in idle then fell to around 400 rpms. No upshift light came on so we will swap out the Cam sensor tomorrow evening.

The saga continues. :)

Jerry
 
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