OK, Working on a 86 SE 6yl. car hasn't run in 6 years. I knew ahead of time the fuel pump was no good. pulled the tank, cleaned it, what a mess! installed new pump, screen, filter. put in new gas, NOW, when I turn the key to ON, the pump comes on for 2-3 seconds, hit start & it'll start & run for 2-3 seconds, shut it off, turn on, pump runs 2-3 sec, then it'll start & run for anothr 2-3 seconds. IT WILL NOT STAY RUNNING ! whats up with this ? Thanks for your help.
Check the injector fuse, the cold start injector runs off of the starter circuit. If your not getting an injector pulse it could be building up enough fuel from the cold start to run but wont stay running because the other injectors are not. Check all of your fuses just to be safe. Good luck Jake
It sounds to me like there is a problem with the wiring at the ignition barrel..there are some wires which should be live in both start and run..and one of those is the fuel pump. It sounds to me like the pump runs in the start position, and then when the key returns to 'run' position, the connection to the pump is broken.. Hmm.although thinking about that, it sounds like the pump runs in 'run', and primes enough fuel into the system to start the engine, and then when it returns to 'run',after starting, the engine has used up the fuel primed in the first 3 seconds, and then cuts out. Have you tried jumping the alds plug to give current to the fuel pump that way? At least you could be sure that current was being supplied fulltime to the pump,whichever position the ignition key is in. If it runs full time then, it is definitely a wiring problem. Nick
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08:59 PM
James Bond 007 Member
Posts: 8872 From: California.U.S.A. Registered: Dec 2002
checked injector fuse, It's OK. checked the new fuel filter, OK too. put the fuel line from the inj rail into a bucket with a hose & jumped the pump, plenty of fuel. STILL, it starts, runs for 2-3 seconds & quits! Tried spraying quick start into the intake when cutting out, Made No Difference. seems to be only fireing in start position. Is There a Sensor Or something I need to check ??? Thanks
Well you need spark, fuel and air Your loosing something when you quit cranking the starter. Pull a spark plug, ground it out on some metal and have someone bump the starter and watch for a spark. It should be bright white not dim yellow. Also if you look behind the water neck under the intake there is a large plug that goes to the injectors, make sure its tight.
You said it has sit for 6 years, I wonder if the fuel pressure regulator is shot. That could cause a problem, I would find a fuel pressure gage and see if it holds pressure after you stop cranking the starter. If it drops right away you have a problem. Check your oil and make sure its not full of fuel.
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04:30 PM
jimbolaya Member
Posts: 10652 From: Virginia Beach, Virginia Registered: Feb 2007
You said it sat for 6 years. If the fuel was not treated, which I'm guessing that it wasn't, you probably got some serious gummed up fuel lines, fuel filter or injectors. there was a guy here in Virginia that had to replace all his fuel lines for that very reason.
already cleaned the tank, new fuel pump, screen, lines, filter, all the way to the injector block. it's not running out of fuel or I'd be able to keep it running by spraying quick start into the intake plenem. It won't even keep running with ether. the current is still present at the hot side of the coil when it shuts down. QUESTION: would somekind of major vacuum leak do this ? IS THE COMPUTER IN A DIFFERENT MODE WHEN STARTING AS OPPOSED TO RUNNING ?
OK, I take that back, it's DEFINITELY a FUEL Problem. I found if I spray ether directly into a port on the intake plenum where I removed a vacuum line, I CAN Keep it running ! So, if the lines are clear, filter is clean all the way to the regulator? (I think thats what it is). Another weird thing, once in awhile when I turn the ignition on, the wipers come on momentarily ! not always, but hapened 3-4 times already & the switch is totally off!( don't know if that has anything to do with it or it's just another piece of weirdness)
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09:04 PM
ltlfrari Member
Posts: 5356 From: Wake Forest,NC,USA Registered: Jan 2002
Does the tach move when you crank it? if not then I'd suggest the ECM is not seeing an ignition signal which is why it's not turning on the pump when you crank it.
Hook up +12V (from the cig lighter say) to terminal G on the ALDL connector, that will turn on your fuel pump, then try it. If it starts and keeps running then the ecm is not turning the pump on after the initial 2 secs priming run when you turn on the ignition and that occurs when it's not seeing the ignition signal. It also sort of indicates that the oil pressure switch bypass circuit is not getting closed.
At least with 12v on the pump and it running it sort of eliminates the pump from the issue and since you know it starts after priming it sort of eliminates any blockage in the fuel system.
PS, the wipers thing is just a dickey switch in the column, mine does that all the time. I doubt it's related to this issue. ------------------ Dave
already did the "hot wire" thing with the pump. it will not stay running even with the pump on all the time. NOW when I turn on the switch, the pump doesn't even come on anymore. if I hot wire it, it will come on. the tach DOES move when it starts. the oil pressure light goes off & the gauge goes to about 50 pounds, then it shuts off. why is the pump no longer kicking in when the switch is turned on ? I can see this car becoming a parts car !
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09:46 PM
May 30th, 2008
gryphon025 Member
Posts: 127 From: Portland, OR 97233 Registered: Apr 2004
I would check fuel pressure at the rail. there is a fitting called a schrader valve(looks like a tire stem). I know it is a new pump, but if they sent you a 4cyl one the car would start, but not have enough pressure to stay running(experience). I think the schrader valve is after the regulator so it won't rule that out. not sure what the pressure should be, hope someone here can fill in that blank.