Help. EFI 76 eldo won't start

[twoten1957]

i have a 76 eldo with efi. stalled while running yesterday and can't re-start. checked electrical connections. replaced fuel filter. can hear fuel pump whine when i turn key on. sprays fuel from relief valve on fuel rail with key on if i push the valve. has a 1/2 tank of gas. unplugged tps and didn't start. if i pour gas into the throttle body it will start and run so no spark issue.

any help would be great. thanks

mike

[carnut]

This is from memory, but I think this car has a fuse or fuses for injectors. Check that possibility 1st. Second, in the base of the distributor shaft housing under a cover are contacts that act like points in a distributor. They allow the right bank to squirt fuel then the other bank. This is not a sequential injector system. It squirts all 4 injectors at a time left side then right, letting the valves determine were the fuel goes. Its called a waste fuel management system. My bet is on the base of the distributor not opening the injectors. Pouring fuel thru the intake can be dangerous!! No fuel normally goes thru the intank manifold, only air. If it backfires, you will loose your eyebrows!! at least.

[cadillac_al]

You might want to borrow/buy a fuel pressure gauge to monitor what the fuel pressure is doing. Many years ago my old Seville wouldn't start and seemed to have fuel pressure. It turned out the fuel pressure stopped while cranking. I can't remember if that was a key switch problem or my fuel pump wire problem. If it runs when you pour gas in it then it has to be a fuel delivery problem. I'm having this problem on a different car (Park Ave), it has 40+lbs of fuel pressure but won't run unless you pour gas in it. A few mechanics diagnosed it as fuel pump problem but I hesitate to change it with 40 lbs pressure. I'm possible thinking it may supply enough pressure during cranking but not enough volume? I'm stumped on this Buick but I eventually got the old Seville running like I mentioned before. Good luck and post back if you figure it out.

[twoten1957]

Thanks guys. I'm going to get back on it today. I was frustrated yesterday that I needed a break. I was thinking the same thing on fuel pressure as well. The shop manual is telling me to check for 39 psi. I assume I can get a pressure gage at an auto parts store? I'll check the contacts on the distrib too. I'll let you know what happens. Thanks...mike

[carnut]

Both the Buick and the Cad must get a signal to cycle the injectors to spray. I would think even if the fuel pressure were 5 LB below spec the car should, at least, start. I would investigate the distributor on both vehicles for lack of injector pulse.

[carnut]

If it were me I would get a "NOID" lite that clips onto the individual injector wire harness to verify signal is reaching each injector to open it to spray.

[alan4video]

If you can pour fuel in the throttle body and it will run the fuel pump by the nearside rear wheel arch has failed. The pump you can hear running is the in tank one. The in tank pump is just enough to supply fuel to the main pump near the wheel arch, which boosts the pressure to the required level.
Regards
Alan.

[drmenard]

I agree with Alan4video that the high pressure pump on the frame could have stopped working... first thing to check is that pump...there are after market pumps that are not exzact replacment that will work.. I would look in to a Walbro, I think 255, maybe wrong number...If you find it to be some other part that is bad I have some used parts...

[twoten1957]

OK thanks guys.
Yes, I do hear the in tank pump running. It must be supplying some pressure though I guess not enough to start which makes sense as to what Alan said. If I turn the key on and hit the relief valve on the injector rail, fuel will spray out. I'll check out the other pump by the wheel arch. What's the easiest way to check for injector pulse? mike

[cadillac_al]

Originally Posted by carnut

If it were me I would get a "NOID" lite that clips onto the individual injector wire harness to verify signal is reaching each injector to open it to spray.

Thanks for the tip, never heard of 'em. They look to be pretty darn handy and there are inexpensive ones out there.

http://www.thepartsbin.com/cartools/...set-678-d.html

[cadillac_al]

Oh yeah, another thing I used to play with on my Seville was the ECM. It was right next to my right foot and I suspect they may have made contact on occasion. A couple times when it would die on the side of the road, I would wiggle the plugs on the ECM and it would start. Not sure if it was coincidence or what but it seemed to work more than once. After all this reminiscing about my fuel injected Seville it's no wonder I converted my next one to a four barrel before I even tried to drive it. That one never left me on the side of the road.

[carnut]

The older these cars get the more prone they become to faulty electrical connections. I can remember when the 76 thru 79 Sevilles were just 5 years old and would melt the wire connector at the back of the ECM because it worked loose. That usually would electrically disconnect the fuel pump, causing the car to quit or not restart. If I remember the fuel pump wire was in the center of the large multi wire plug. As you know, the ECM is centered under dash just below the ash tray. look at that plug for any heat related damage evidence. Wouldn't that be excellent if the plug was just loose!!

[twoten1957]

Wow. That's cheap. Great idea. I'm going to order one tomorrow. Wish me luck!

[carnut]

Never read the solution to the no start??

[twoten1957]

Hey-can anyone recommend a cheap fuel pressure gauge i can attach to the pressure relief valve on the fuel rail? Been traveling alot for work so just getting back into this issue. Thanks