This is really stange ...My car is cursed or something.

I had my car running perfectly fine today with open headers so I put the y-pipe and rest of the exhaust back on to go take it for a ride. I turned the car on and it idled smooth at 850RPM for about 45 seconds as I checked for leaks. Then I got in and gave it a few revs but after about the 3rd rev the car stumbled and tried to die but then just went right back to 850RPM so I glanced down at the tach and it was pinged at 8000RPM. I figured something came unplugged or a blew a fuse in the gauges so I went to turn the car off and it would not turn off for about 5 seconds. When I turned it off the car was still idling smooth. It wasnt like it was trying to die or anything ...it was running perfectly smooth for those 5 seconds. The other weird thing is that the tach stays at 8000RPM. When you put the key in the on position the tach kinda falls down to about 5000RPM then pings back up to 8000. Also when you try to turn it off the tach slowly falls to about 3000RPM when the car dies (then goes right back up to 8000 again)

Keep in mind the car is idling smooth at 850RPM (or so) the entire time the tach is going crazy and not wanting to turn off. Could something be wrong in the distributor? The distributor is a pretty old stock HEI one with a new coil, cap, and rotor. We didn't touch anything under the hood and it was running fine with open headers but now with the exhaust on its acting like this. Any ideas? I'm really lost on this one.

 

that is a pretty bizarre problem. The first thing i learned in my electrical classes was when you have bizarre problems like that, check the grounds. I'd just find as many grounds as i could related to the ignition and tach and clean them. if that dosnt help you.......you might have your hands full for a while.

 

Well I went out and quickly checked the grounds, fuses, and wires. I didnt see anything out of place. I also checked to see if the distributor was getting power after the ignition was turned off ...it isn't.

I started it and noticed it was running pretty rich. Black smoke at idle and I pulled out a plug and it was pretty black too. The carb is right out of the box ...I have yet to monkey with it. What I still dont understand is why it runs so perfect after its turned off and not getting spark. It doesn't sputter or anything ...it runs as if you never took the key out then just suddenly cuts off like normal.

 

are the headers long tubes or shorties? if they are the shorty style you may have burned some wires when you ran it open, i did this on mine when i installed the headers on my car. since they didnt fit the stock y-pipe i had to run it open till i could fabricate one, well i melted the wire from the battery to the starter. anyways i would check to see if any wires are burned or melted this may be your problem.

 

is it like pre-ignition where you shut it off and it keeps running and sputtering?:lala: :lala: :lala: :lala: :lala:

if it isn't you are full of stop tryin too con us

 

Um... what's your problem? You don't have to put twenty of those stupid little gifs in every one of your posts. If you aren't helping, don't post!


I don't think you melted anything, maybe your tach is just telling you to replace it.

 

rezinn: my tach is probably the last of my problems. I don't think it would just break along with my car not wanting to shut off the second I get done putting the y-pipe and everything back on

Halberto45: What in the heck are you talking about? I think you lost us all on that one. Its NOT sputtering after I turn the key off ...it is running PERFECT for 5 seconds even thought my distributor is getting no power.

Tonight I'll recheck the wires (they all looked fine though), retard/advance the timing a little, and maybe change the spark plugs.

 

I'm completely lost on this one. Every single wire I could find I checked over. Everything looks fine. Changing the timing doesn't help either.

 

have you actually checked everything or just looked at it and thought it looked ok. Like i said before loosen every ground and clean it and then screw it back in. You say you're getting no power to the distributor and the engine still runs.....i'm afraid thats quite impossible, as you say it runs fine; not like its pre-detonating.

Unplug the distributor and see what happens when it starts doing this.

 

I figured it out. My electric fans are hooked up the a toggle switch and my friend wired it up into a strange place in the fuse box. When you turn the fans off the car shuts off normally, with them on the car stays running for those few seconds. I just need to rewire the fans.

Thanks everyone for the help.

 

So, what was happening was probably that the ignition + wire to the distributor was wired to an unswitched (always on) source?
I've had this happen to me when converting over to hei on older cars. You just learned how to "hot-wire" a chevy. =) haha

Hellraiser

 

Since my car was originally TPI we had the fan hooked up to the "FUEL INJ" (or whatever) fuse which was hot in run. So for some reason when you shut the car off the fans would keep running for those few seconds, then when the fan turned off so did the rest of the car