: '82 Fleetwood D'elegance coupe problem :(



Kadillac G
11-16-11, 04:18 PM
Hey guys,

I just bought an 82 fleetwood coupe that currently does not run. I thought it was the
fuel pump (because i didnt hear it when i tried to start the car) so i replaced it. The car still turns over but does not catch. After testing, i found that i was not getting power to the pump. Im getting 12-11.9 volts at the relay but thats as far ( from what i tested) as the power goes. I followed a wiring diagram but its a little confusing. Anyways, the fuel
Pump is not getting power and need to know if the ecm would have anything to do with it not receiving power (as mentioned by the gentleman who sold it to me). Oh and by the way my ignition switch looks as if someone tried to steal the car so now it can be started with a flat head, would anything cause this problem?

http://i1192.photobucket.com/albums/aa332/gabeluciano/af627530.jpg
http://i1192.photobucket.com/albums/aa332/gabeluciano/5871a446.jpg

Kadillac G
11-16-11, 04:29 PM
Oh and btw, i went thru all 152 pages of this forum to find answers but the ones that had similar problems never responded what the exact problem was so i tried to find out but to not avail. Thanks for any suggestions

aeronca36606
11-16-11, 05:25 PM
Give the engine a shot of starting fluid. If it runs for a second you have a fuel delivery problem. If it does not, Then you have an ignition problem. The fuel pump only runs for a second or two when you first turn on the ignition. This pre charges the fuel system. It should also run during cranking. After starting it continues to run unless there is a loss of oil pressure or the engine rpm goes to zero.

Kadillac G
11-16-11, 05:49 PM
Give the engine a shot of starting fluid. If it runs for a second you have a fuel delivery problem. If it does not, Then you have an ignition problem. The fuel pump only runs for a second or two when you first turn on the ignition. This pre charges the fuel system. It should also run during cranking. After starting it continues to run unless there is a loss of oil pressure or the engine rpm goes to zero.

Ok i sprayed it like you said it ran for a second then died. Im pretty sure its a fuel problem because i tested the connection under rhe rear bumper with a multimeter and got nothing while my assistant turned it on. Since i know in getting power at the relay i was thinking of running a new wire from the relay to the wiring harness under the rear bumper. But ONLY IF i know for fact it goes from the relay/fuse box directly to the fuel sending unit

carnut
11-17-11, 01:57 AM
Replace the relay, simpler. Also if the harness to the oil pressure sender is unplugged or loose, damaged, you will get no power to the pump. Its mounted just above the oil filter on the filter adapter. In that location, its very close to exhaust manifold heat. The ECM provides a ground to complete the circuit. While cranking, if the ECM sees no oil pressure it wont complete the ground.

Kadillac G
11-17-11, 08:13 AM
Thanks, i'll let you know how it went. The relays are brand new. Anything easy, i already fixed/replaced lol. Well except the oil switch but ill be doing that today! Thanks again!

Kadillac G
11-17-11, 01:16 PM
Thanks to the help of Carnut, i may have found the problem. In accordance with with wiring diagram what he said is obviously true. So after replacing my ignition switch ( at which my horn wont cut off now) i looked at the oil pressure switch and harness. The oil pressure switch is worse than the harness

http://i1192.photobucket.com/albums/aa332/gabeluciano/d248c5a8.jpg

Kadillac G
11-17-11, 01:20 PM
Now, i have a new oil pressure switch, question is how do i fix this harness? I believe its uncleanable(?). Can i cut it at the wires and splice another harness from another HT4100 into it? Or is there an easier way?

aeronca36606
11-17-11, 02:06 PM
Check with your local auto parts supply house. A lot of them carry switch and harness pigtails. They may have one for the oil pressure switch. The same plug is used in a lot of GM models.

Kadillac G
11-17-11, 03:12 PM
Check with your local auto parts supply house. A lot of them carry switch and harness pigtails. They may have one for the oil pressure switch. The same plug is used in a lot of GM models.

Yea i picked up a new switch but ill check for a new harness. Either way, its ok to cut this one off right?

ehall
11-17-11, 07:29 PM
Wait until you have the pigtail/connector before cutting anything.

Most likely the new one will be a connector with a couple of wires hanging out. If so then just cut the wires you have there and use a couple of butt connectors to attach the pigtail, and cover them with some shrink wrap to prevent them from grounding out.

Kadillac G
11-17-11, 11:10 PM
Wait until you have the pigtail/connector before cutting anything.

Most likely the new one will be a connector with a couple of wires hanging out. If so then just cut the wires you have there and use a couple of butt connectors to attach the pigtail, and cover them with some shrink wrap to prevent them from grounding out.

Thats good advice right there thanks. I was ahooting to find a good one at the junk yard but ill check advanced or autozone tomorrow.

aeronca36606
11-18-11, 04:58 AM
I believe the part number is but double check it.

Oriley's: BWD PT5832

NAPA: ECH EC428 Expensive

carnut
11-18-11, 10:46 AM
Routing of that harness is important as you see. The splice should be long enough to keep it away from the exhaust. Wish I could be there when it starts!

Kadillac G
11-18-11, 01:07 PM
Routing of that harness is important as you see. The splice should be long enough to keep it away from the exhaust. Wish I could be there when it starts!

Me too bro, if it wasnt for you, i would have gave up on my dream car. Ive wanted this car since i was in the third grade (im 28 now). My wife gets tired of me talking about it so much lol thanks again and ill make sure to do as you said about routing because i was just gonna cut like three inches back and splice it. Good looking out man. I appreciate everything!

carnut
11-26-11, 03:28 AM
Does it run???

Kadillac G
11-26-11, 09:44 PM
Does it run???

Almost. I was actually working on it today. The fuel pump now has power and is sending fuel to the tbi. Problem is the injectors are not getting power. So my friend unhooked the connectors at the injectors and as I was turning the engine he jumped the injectors directly from the battery and my car ran beautifully. We didn't run more than like 5-6 seconds but he told me the injectors was spraying the way they should. So I have. We hope for the car. But my question is, the power for the injectors is supplied by the ECM right? Guy I bought it from said he had ppl look at it and determine it was the ECM. Since I can't buy an ECM anywhere (only prom chips) can I get one from a junkyard and use my prom chips? Btw there's a leak in the area where the ECM sits so I guess it's plausible for it to short out

carnut
11-27-11, 02:22 AM
The ECM provides a ground completing the circuit in 98% of its control. It rarely provides power. If it does, its less than 5 volts. Yes the ECM can be swapped using your PROM.

Kadillac G
11-27-11, 02:51 AM
The ECM provides a ground completing the circuit in 98% of its control. It rarely provides power. If it does, its less than 5 volts. Yes the ECM can be swapped using your PROM.
So in your expert opinion, what would cause loss of power to the connectors for the injectors ? It was checked by a volt meter.

carnut
11-27-11, 03:02 AM
So the voltmeter showed no power? If so, my guess would be the ECM, assuming the harness wasn't pinched under the air cleaner spacer which could short out the circuit to the ECM. You did check both injector fuses in the relay panel under the steering column right?

Kadillac G
11-27-11, 03:18 AM
So the voltmeter showed no power? If so, my guess would be the ECM, assuming the harness wasn't pinched under the air cleaner spacer which could short out the circuit to the ECM. You did check both injector fuses in the relay panel under the steering column right?
I made sure to check the fuses after finding no power. But yea, no power to the connectors

ehall
11-27-11, 01:16 PM
I don't know about your 82 so this is some speculation. With most FI cars, the computer looks at the amount of air flowing through the engine and applies the correct amount of fuel to match. On my 85 there are also two 1.5A fuses, one for each injector, under the dashboard. If neither of the injectors are firing then my guess is that it's a computer error. It's also possible that both fuses are blown.

I would try a replacement ECM for grins. You can find them for $25-40 on ebay and junkyards and such.

Kadillac G
11-27-11, 01:27 PM
I don't know about your 82 so this is some speculation. With most FI cars, the computer looks at the amount of air flowing through the engine and applies the correct amount of fuel to match. On my 85 there are also two 1.5A fuses, one for each injector, under the dashboard. If neither of the injectors are firing then my guess is that it's a computer error. It's also possible that both fuses are blown.

I would try a replacement ECM for grins. You can find them for $25-40 on ebay and junkyards and such.
I figured as much. Thanks bro. I found a ht4100 in a junkyard so I'll go pull the ECM out tomorrow since a lot of ppl say it's rare for the ECM to go bad. I believe the only reason my went bad is because water leaked on/into it

Kadillac G
12-01-11, 01:44 PM
Ok so I come to find out that all HT4100 ECM s are not the same. Apparently I can only use an ECM from an '82 4100 engine. Before I go spending an absurd amount of money for this thing, anyone got any suggestions? Problem still remains about lack of power to the fuel injectors

ehall
12-01-11, 02:02 PM
Check on car-part.com first

Is your 4.1 the V6? I can't find an ECM for the v8.

Kadillac G
12-01-11, 06:37 PM
Check on car-part.com first

Is your 4.1 the V6? I can't find an ECM for the v8.

Mine is a v8 as well. The part number from cardone is 77-5650. eBay it, and you'll find a couple but they want some crazy money for remans

carnut
12-01-11, 10:30 PM
In my foggy memory, the ECM was the same for many years but the PROM had to be inserted into the replacement unit.

Kadillac G
12-02-11, 01:39 AM
In my foggy memory, the ECM was the same for many years but the PROM had to be inserted into the replacement unit.
And that's what I thought, but I went to the junkyard today and found an '83 and 84' coupe deville both with the same ECM but they were different from mine. Mine has TWO prom chips while the cars in the junkyard have only ONE. WTH?!? BUT, mine is apparently NOT FACTORY! It says reman on it and the ones in the junkyard both had stickers saying GM

Kadillac G
12-05-11, 12:06 PM
ook the old ECM out and put in the one from an '83 in.
Connected the battery cuz I don't leave it connected.
Checked the injector fuses. Found one to be blown. Replaced it with a 5 amp. (yea I know I shouldn't but that's all I had) turn the key, and SHE STARTED! But died cuz the fuse blew :( The other injector fuse never blew, so with that being said, is it safe to assume that the original ECM is still good? And where the hell do I go from here?

carnut
12-05-11, 12:25 PM
You back trace the wiring harness for that injector. Start at the throttle body 1st. Easy to pinch the harness under the air filter spacer as I mentioned earlier. You also said earlier that you checked those fuses and both were good? And since then the battery's been disconnected. So why was one blown before you turned the key this time?

Kadillac G
12-05-11, 12:38 PM
It must've happen when I replaced those fuses then when I tested and hard wired the injectors it blew then. But I'm going back in a lil bit to look at exactly what you mention and trace lines. Thanks for all your help bro.

carnut
12-14-11, 12:53 PM
Does it run?

Kadillac G
12-15-11, 12:16 PM
Does it run? Im actually sitting next to the car as I write this. This is what I've done so far today: first thing was to check and trace the injector wires, they turned up clean and intact. No cuts, pinches or anything. Ok now, the ECM that is for an '83-'84 was still in the car. I put a new 3 amp fuse in the fuse block and turned it to bulb test run. The injector fuse blew. So I went under the hood and switched the injector connectors around. Put a new fuse in and repeated the process. The same fuse blew. So apparently it doesn't matter which injector is connected to that wire, that line will always blow. So I put the "original" ECM back in, replaced the fuse, turned the car to test run, fuse DID NOT BLOW. but when trying to actually turn the car on it didn't try to catch. But with the ECM that doesnt belong in the car, the car will turn on and run until the injector fuse blows out. The original ECM that came with the car is no good is it?

Kadillac G
01-09-12, 12:52 PM
Ok well I put in a new ECM in the car new injectors, and the car STILL won't start. But the car will run pretty damn strong when I pour a lil gas down the throttle body. No longer am I blowing the fuel injector fuse. When I try to start the car and check down in the ports of the throttle body, it's dry. I checked the fuel pressure port and I got fuel going to the throttle body.

83CADMAN
01-13-12, 07:14 PM
Did you connect a pressure gauge to the port and get a pressure reading?
Low pressure could be caused by a pluged fuel filter or even a pluged strainer in the gas tank

carnut
01-14-12, 12:45 AM
There is a tool called a "NOID tester" it plugs onto the injector and lights up if power is getting to the injector. This fuel pump requires very low pressure to spray fuel. Can you rent a pressure gauge from an auto parts store?

Kadillac G
01-14-12, 02:11 AM
Did you connect a pressure gauge to the port and get a pressure reading?
Low pressure could be caused by a pluged fuel filter or even a pluged strainer in the gas tank
I put a brand new fuel pump, strainer and fuel filter.

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There is a tool called a "NOID tester" it plugs onto the injector and lights up if power is getting to the injector. This fuel pump requires very low pressure to spray fuel. Can you rent a pressure gauge from an auto parts store?
Then I'll get the pressure tester tomorrow from autozone. Can I get the noid tester there also? And if not, where can I find it? Is testing the connectors with a multimeter the wrong way?

ehall
01-14-12, 01:33 PM
Stuff that flickers on and off is hard to test with a multimeter. The pros use an oscilloscope. I use a small 12v interior light bulb, you can see it flash on and off.

Kadillac G
01-14-12, 05:33 PM
Stuff that flickers on and off is hard to test with a multimeter. The pros use an oscilloscope. I use a small 12v interior light bulb, you can see it flash on and off.Hmmm that's a good idea. If I turn the car to bulb test then the injectors should be pulsing the way they would if the car was running correct?

carnut
01-14-12, 11:24 PM
No, the engine must be cranking over for the injectors to pulse. Turning the key to bulb test only powers up the Idle speed motor anticipating a start up.

Kadillac G
02-09-12, 07:30 PM
Ok turns out the reman injectors were locked up. So I paid for new ones from autozone. Before I out the new ECM in, the fuel pump was working (installed new) but now I'm not getting power to the fuel pump connectors underneath the rear bumper. Only place I'm getting power is at the relay (which is also new) and to remind, I replaced the oil pressure sensor and it's connector. Could the MAT sensor or coolant temp sensor tell the ECM to shut power off to the fuel pump?

83CADMAN
02-10-12, 02:25 PM
Had a similar situation with my 83 Eldo, No power to the FP harness connector at the rear of the car. In my case I kept blowing fuses. The relay checked good so I started back at the tank and chased the wiring, all tested good, but still no power to the pump.
Turns out the wire to the oil pressure switch had migrated up against and melted to the right ehaust manufold shorting the circut.
I too replaced a lot of stuff chasing this problem. Good luck.

carnut
02-10-12, 09:14 PM
Power is supplied for only a few seconds just after the key is turned to either "run" or the "start" position. While cranking, fuel should spray from both injectors assuming the oil pressure sender sees oil pressure. "Locked Up" injectors? what does that mean? You have power to them, but they do not spray? Wouldn't it be cheaper and quicker to pay someone to diagnose this. diagnosing an engine that doesn't start is much easier than an engine that starts at times.

Kadillac G
02-10-12, 10:03 PM
Yea I supplied power to the old injectors directly from the battery. Burned both of them. Yea I found that the oil pressure switch AND the connector was burned so I replaced both with brand new parts. Would it matter if the fuse for the battery at the fuse box blows EVERY SINGLE TIME I PUT a fuse in the block? I'm very good with cars and never ran into a problem I couldn't fix but the problem is this engine is truly a one of a kind pain in the ass. I don't think regular mechs can diagnose this car

carnut
02-11-12, 12:32 AM
The next part you should buy is the factory service manual! This is a very simple 2 injector system. I say again, if its not running a mechanic will be able to diagnose it. The mechanic with the factory manual should have no problem. A blowing fuse is a result of a bare wire touching metal somewhere.

83CADMAN
02-13-12, 03:13 PM
Trace the wires and look for the short. Its an intermitant problem. (sometimes it starts and sometimes it dosent).
More than likely a bare spot on a wire intermitanly touckes metal like carnut said. A couple of inches of electrical tape and wala.
The section of harnes suppling the starter and oil pressure switch is most vunrable near the hot exhaust manifold. Its dark and hard to see the harness from topside. Go under and shine light up and past the starter. not much room to work, but the starter drops very easy making for enough room to manuver to disconect the starter and pressure switch. Pull the harness up topside to carfully inspect the wires, removing the harness sheath.
This is what I had to do just to inspect find and repair the short in my fuel system. I started at the tank, removing the pump and bench testing it (it was a new one). Then I meter tested each run, conector to conector (pulling interior panels, thresholds, seatbelts, seats) and still didnt find the short until I inspected the last and only remaining run to the oil pressure switch.

Kadillac G
02-13-12, 06:55 PM
THANK YOU GUYS!! I'm going tomorrow (since I keep the car at another house) and spending the entire day doing what you guys mention. Thank you again Carnut and 83Cadman!!!

Kadillac G
02-23-12, 11:13 AM
The car runs!!!!!!!!!!!

83CADMAN
02-23-12, 08:58 PM
So...What was it and How did you fix it?

Kadillac G
02-24-12, 10:07 PM
Well I bought the actual troubleshooting book the mechs used in 1982 in the dealership. After countless hours of studying the diagrams I finally started to "properly" troubleshoot the car. 83cadman I don't know how much of this thread you've read, but in the beginning there was a host of problems. One was the 20 amp battery fuse kept blowing. Well after changing the ECM and injectors, I put the fuse in and it didn't blow! I tried to turn the car on and it ran. But when I first got the car it was a mess. No "power" to the injectors, no power to the fuel pump, got power to the pump but fuel not reaching the tbi. But now I only have one problem left but it's nothing that keeps the car from running. The gasket for the injectors broke so one of them gets flooded on top of it. No big deal. But thank you guys for all your help. I almost gave up and sent the car to the junkyard. Btw, the ht4100 in there now runs damn strong. So I'm gonna keep it in there until it blows. My ultimate goal is to put a 425 in there one day ;)

Dan Craig
11-11-12, 03:53 PM
I have a similar problem with an 82 Cadillac DeVille with Digital Fuel Injection. Was running fine, just a little rough idling and some hesitation above 60 mph. Started hard the other day, kept dying despite holding the gas pedal down, surged, coughed, finally died and wouldn't restart. If I spray starter fluid in the newly cleaned throttle body, it runs until I stop spraying. Doesn't seem to be getting fuel. Replaced the fuel filter, no luck. Of interest, no fuel pumped out of the open supply line when I tried to start before I put the new filter on. I can hear the fuel pump engage for two seconds with the key in On position, so I know the fuel relay is working and suspect the pump is as well. What could be causing the car not to start?

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I have a fuel problem with an 82 Cadillac DeVille equipped with Digital Fuel Injection. Was running fine, just a little rough idling and some hesitation above 60 mph. Started hard the other day, kept dying despite holding the gas pedal down, surged, coughed, finally died and wouldn't restart. If I spray starter fluid in the newly cleaned throttle body, it runs until I stop spraying. Doesn't seem to be getting fuel. Replaced the fuel filter, no luck. Of interest, no fuel pumped out of the open supply line when I tried to start before I put the new filter on. I can hear the fuel pump engage for two seconds with the key in On position, so I know the fuel relay is working and suspect the pump is as well. What could be causing the car not to start?

carnut
11-11-12, 04:09 PM
When my fuel pump quit on my 84 Eldo at 75 MPH, it worked when tested out of the tank but had no volume. So, the pump can still be heard to run but not be strong enough to get up to at least 9 PSI. It must have a minium of 9 and a max of 12 PSI to work. The "sock" filter on the pump was clogged, which caused the pump to fail on my car. There is also a short hose joining the fuel line on the float to the pump. If that hose is split and the fuel level is low, it will suck air, not fuel.