Cadillac Seville / Cadillac Eldorado Forum Discussion, 1996 Eldorado Fuel Pump Diagnosis Help! in Past Cadillac Vehicle Discussion; The other night my Eldorado died at a stop light. The engine cranks and sparks -No fuel pressure though which ...
The other night my Eldorado died at a stop light. The engine cranks and sparks -No fuel pressure though which leads me to the fuel pump. The fuse and the relay for the fuel pump are both good. The next thing I wanted to check was the wiring to the fuel pump without having to drop the tank. I own a 2 volume service manual (GMP96EK) for my 1996 Cadillac Eldorado which I had purchased from HELM a few years ago. Now many years later I am having a fuel system problem. The issue is that when I reference the section pertaining to the FUEL SYSTEM the index lists SECTION 6C in book number 2, the problem is that SECTION 6C does not exist exist in either book 1 or 2. My Book 2 contains section 6B, followed by section 6D. Section 6C was truncated despite it being referenced in the index, In all these years of owning these books I have first noticed this issue since a fuel problem has developed. Well after an exhaustive search I think I found the wire harness feed leading to the fuel pump under the center of the back seat.
The problem is that I have no schematic/diagram of the fuel pump circuit to test it for power. Does anyone know more about these wires? A fuel system schematic would help immensely, but just the colors of the fuel pump power, and sending unit wires would work as well. I've read elsewhere in this forum that these wires are prone to failure. Any help is appreciated.
FYI After researching through the fuse block detail, The book listed gray as a possible fuel wire color. There were two gray wires in the trunk feed, one heavy 10 gauge and another smaller gauge wire. I took the chance with the heavier one and tested it with my test light. I guess I guessed correctly because with the key in run it the bulb lights for 2 seconds and goes out. Also the bulb is on when the key is in the cranking position just as the PCM protocol requires. I now know the PCM and the wiring up to that point is not the culprit. The tank comes off tomorrow! I wonder if it is a dead motor or shorted wiring from the connector to the motor/sending unit. I experianced no fluctuations in the fuel gauge readings. I will post another followup. P.S. A new AC fuel pump from GM with the sending unit lists at $462.11 + tax and wholesales for 323.49 + tax.....
I replaced the one in my Blazer a few years ago with an AC new part. It lasted a little longer than the 1 yr warranty! Friends in the business have been recommending aftermarket in some areas. Fuel pump is one. Remember...these are all opinions based on limited (even if you are a professional mechanic) experience. Your actual experience will vary.
Anyway, I would't hesitate to get an aftermarket but think I would only go new. The rebuilt one on ebay might have a new pump in the old module. I'd still be leary of it unless I was sure.
Automobile(s): White Diamond '03 DHS (with floor shift)
Re: 1996 Eldorado Fuel Pump Diagnosis Help!
In years past I had 3 Blazers. I replaced fuel pumps in those things more often than plugs (or anything else for that matter). Each one had it replaced twice and the last one was ready for the third when I traded back to the dealer I bought it from. Like you, one lasted just 13 months. Some were OEM and some where aftermarket. GM never would admit a problem but it was obvious to me that there was one (no one is that unlucky). I always suspected the high fuel pressure (60 psi) on the Vortec. Never went back to a Blazer or Chevy again.
Well I didn't get the tank out today got tied up with other things to do. Anyway, I'm trying to figure how to drain off at least some of the fuel since the tank is 3/4 full. That 96 E/K GM service manual actually mentions a tank draining procedure of some sort, but they left it out of the book again??? I was hoping to avoid the gasoline bath scenario if possible. I tried use a siphon but the inlet hose has too many turns it to reach it or it may have an anti-siphon baffle.
Anyway, I am going to buy a new aftermarket pump. I cannot see the sense in buying another AC which failed at 66K with no improvement in it's design. After searching the web I found several brands of new aftermarket pumps. Carter, Delphi, Airtek, KEM and others all sell new pump modules for this car. They vary in price from $180.00 - $330.00. I like KEM parts the most. I personally never had any problems with their parts. but I haven't found one for less than $300.00. KEM sells a pump motor rebuild kit (EFP10988K) alone for the module, but I found no one online who stocks or prices it. The best deal I found was the company DirectAuto.COM, they sell the pump motor alone for $44.95 along with a lifetime warranty! Another interesting thing I found was Carter markets a heavy duty tank wire harness (888544) for that pump for around 15 bucks. I WONDER WHY!!! I'll probably go the route of 45 dollar LT pump motor with the Carter harness for assurance, but I'll wait until I remove it first for inspection. Thanks to everyone for your replies -Mike