95 SC300 won't shut off

Tony320 · 10-28-09, 06:08 PM

So I go to get in my car and drive to the supermarket this afternoon, and realize I forgot my wallet. well, I turn the key off and pull it out of the ignition, and realized that the car is still running, extremely rough and at really low idle. I think well that is no good so I put the key back on and turned the key back to "on."

The Sc300 goes back to normal idle and everything seems normal so I turn it off again and it still won't shut off. I don't really want to leave my car in the parking lot, idling while I go get a wrench to pop the batter cable off since I live downtown and its not uncommon for people to wander through my parking lot since I live next to a sketchy dry-cleaner. Since my car is a stick, I thought well maybe I can just kill it by dropping the clutch. Doesn't work, car chugs along lurching forward with each crank of the engine.

So I resign myself to the possibilities of leaving my car running with the keys in it in the parking lot and go grab a wrench, come back, and disconnect the battery. The car still runs, but goes back to low idle (like when the key was out). So I turn the key off and finally the car shuts down.

Anywho, anyone else had this problem? I searched around for a while and found a ton of posts where the car would not start back up but not any about a car that wouldn't shut off.

JamaicanSC · 10-28-09, 06:13 PM

This is a first!

sueno2jz · 10-28-09, 06:54 PM

hmmm, ive seen this on a few other vehicles that ive installed on, do you have an aftermarket amp? ive seen a couple of amps malfunction where they keep sending 12v back to the ignition through the remote wire keeping the car running with the key removed...

Tony320 · 10-28-09, 09:14 PM

Yea, I prolly should have mentioned that the car is bone stock, no mods. I'm going to go ahead and take it in tomorrow, I'll post the verdict once I have it for future reference. In the meantime if anyone has any other thoughts, feel free to post em.

lengnoou · 10-29-09, 12:33 AM

Its close to Halloween......

Tony320 · 11-03-09, 08:33 AM

Alright I took it in and I guess the fuel control shutoff relay went kaput. $14 and some labor later, car runs great. Makes total sense, fuel keeps going in, motor keeps turning over, alt keeps making spark: car isn't going to turn off. Anywho, that isn't the exact right name for the part, pretty much from memory of the original phone conversation, the invoice merely states EFI relay. Anywho it should give people a start if they run into his in the future.

dizzyroc · 11-03-09, 08:36 AM

only time ive seen this is on the diesel tugs at the airport lol . good to hear its fixed

GRN MNSTR · 11-03-09, 09:21 AM

haha that's pretty crazy...I would've freaked out leaving my car running lol...then again I live in Atlanta, and you're in Iowa?

Crazy story but yeah that makes sense, glad you got it all worked out.

Tony320 · 11-03-09, 02:56 PM

Quote:

Originally Posted by GRN MNSTR

haha that's pretty crazy...I would've freaked out leaving my car running lol...then again I live in Atlanta, and you're in Iowa?

Crazy story but yeah that makes sense, glad you got it all worked out.

Heh, yea I was a bit worried about it. I actually live in Omaha right now, downtown in an apartment building, so its pretty heavily traveled. Contrary to popular belief though, there are cities in Iowa too!

Of course that doesn't really matter either, My buddy used to live in a small town of about 1800 people and his car was stolen right from in front of his house! Apparently two escaped cons stole a car in Illinois, drove to Iowa, stole his car, and drove to kansas city. I guess they were Heading to Mexico? Oh well, it was an '87 tercel... he left it in the impound.

CrazySC300 · 11-03-09, 03:55 PM

This thread scares me, I have the same year and model SC....

codetoad · 11-03-09, 04:19 PM

my '92 5 speed had a similar problem, only the fuel pump would not turn off, and I have an aftermarket walbro. the car wouldn't stay running, just the fuel pump. I could not figure out why it would keep running with the key out, and I even replaced my EFI main relay (this is the one causing your problem correct?) and it didn't work. I found that my ECU's main relay was staying on with the key out of the ignition, so i wired a switch in to cut power to the main relay. My car runs fine sometimes, and then, like you stated, will idle really low and almost stall out. Sometimes it won't hold an idle at all, and if i clutch in without giving gas, the car will die, while i'm driving. Scary! I haven't messed with the car in a while since i hardly drive it, but it is definitely a pain in my rear

titanSC · 11-04-09, 09:58 AM

Exactly the same happened with my stock auto 94 sc300 2 months ago. Car wouldn't shut off + idle extremely low with the keys out. As obvious as it seemed, the engine was still getting fuel keeping it running so I pressed the gas a couple of times with the keys out and it finally went off. I didn't change the relay but it hasn't happened again...