Shut car off, feul pump off, car keep's going?

[supraman]

I put in an inline, low pressure fuel pump, and hot wired it to a switch.

The wiring: From battery to an inline fuse(30amp) to switch. From acc on switch to the fuel pump. From ground on switch to Firewall to ground it.

When i wired the fuel pump i just put it back where the OEM pump went and wired the power wire on the pump to the green power wire at the pump coming from under the passenger seat area.

Then wired the ground on the pump to the black wire that ran with the green power wire, assuming it was a ground.

It work's great, come's on when I hit the switch, shut's off when I turn it off.

But when I had it running and turned the pump and the ignition off, it kept running, stumbled a hair, then died. What is causing this car to keep running if the ignition is off and the pump is off?

Is it left over carb gas burning off ? Or an ignition problem?

[Arne]

How long did it run after switching the key off before it stumbled and died? 5 seconds? 15? More?

[supraman]

Arne,

Your the man! Alway's helping me out, thank's allot.

She ran / stumbled for around 5-10 second's then died out.

[bigoak]

Either timing issue or low octane fuel or both (most likely the latter)...

You have dieseling...the compression of the vehicle is sufficient to cause detonation of a low octane fuel...dump the gas and get some high test...mine did the same until I made the switch...

[supraman]

Either timing issue or low octane fuel or both (most likely the latter)...

You have dieseling...the compression of the vehicle is sufficient to cause detonation of a low octane fuel...dump the gas and get some high test...mine did the same until I made the switch...

Thank's Bigoak,

I'll give it a shot, that input help's.

[Arne]

That's what it sounds like to me, too. It's been a LOOOONG time since I've had a car that dieseled. Seems to me that a timing change might fix it as well. Can't seem to recall this morning which way to go though... :stupid:

[doradox]

Timing won't directly cause dieseling. Once you turn the key off, no spark=no timing. However, retarded timing will require a larger (relatively) throttle opening to maintain idle speed. Larger throttle openings increase the risk of dieseling. Lots of cars used to have a solenoid which opened the throttle enough for idle when the key was on and then closed when the key was turned off to reduce dieseling. You would actually adjust the idle by adjusting the soleniod bracket. Some had a similar setup on the idle fuel circuit to shut off fuel and eliminate dieseling.

Steve

[Nigel1943]

Just wondering if you are getting a feedback from the alternator which will still give power until the engine stops turning. It would mean the ignition would have to be permanately on.

[supraman]

Just wondering if you are getting a feedback from the alternator which will still give power until the engine stops turning. It would mean the ignition would have to be permanately on.

How would i find out? How can I test for this? Is there a quick fix for it or a thread on it that I might could learn some info from?

Thank's for your time...

[Nigel1943]

Not quite clear from your post exactly how youv'e wired the pump. You appear to have supplied power to it twice, once thro a switch from the battery and again thro the OEM green wire. Am I reading this right?

[supraman]

Not quite clear from your post exactly how youv'e wired the pump. You appear to have supplied power to it twice, once thro a switch from the battery and again thro the OEM green wire. Am I reading this right?

No, but i did leave a part out. Thank's for the correction.

I did use the green wire but just cut it and connected my red power wire to it, under the passenger seat. So just one power line going to it.

I ditched the ecu, so i had to hard wire it to a switch. Swaped to SU's.

[Nigel1943]

No, but i did leave a part out. Thank's for the correction.

I did use the green wire but just cut it and connected my red power wire to it, under the passenger seat. So just one power line going to it.

I ditched the ecu, so i had to hard wire it to a switch. Swaped to SU's.

So you have the pump on a seperate switch and the ignition off the ignition switch, right?