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1993 sedan Deville
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15 Posts
Discussion Starter #1
Hello

I have a 1993 deville 4.9L and it sumbles at idle. I bought the car for my dad and it was sitting for 4 or 5 years. Anyways I started fine after a new battery and new oil . Anyways I wanted to see what the e test would show. It failed. I now replaced all the following parts with ac delco parts. Plugs ,wires cap,rotors 02 sensore.I still have a slight stumble at idle. I now also found # 7 injector not working. Tomorrow I will see compression.
I have a couple of questions.
1)How do you set timing on these cars. I read something about jump A B pin? and what should base timing be?

2) What are injectors numbers? Are they 19lbs and what other car can I use from.

Thanks
Mike
 

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1992 Sedan Deville, 1984 Lincoln Town Car
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759 Posts
there should be a label in the engine compartment with the info needed, but It's pretty standard, a timing light with the inductive lead on #1 spark plug. Your timing marks on the crank shaft may be dirty and need cleaning; pay no attention to the bolt-sized thingy sticking up there.

Remove the air cleaner assembly after the engine is warmed up to normal temp. Jumper the A & B pins of the ALDL connector (under the dash ashtray area) while NOT in diagnostic mode and a "SET TIMING MODE" message will display on the ECC panel.

Start the engine and check the setting to 10 BTDC @ any speed less than 800 rpm. If it needs to be changed, I guess you need a special tool (distributor wrench, Thank-you GM) to loosen the Dist. Remove the ALDL jumper when you are finished or the engine will run at the base speed. the computer will take it from there and auto set the timing.

As for the fuel injectors, just about any year close to yours will do. I say that because I used some on my 92 that were a 4.5 engine from several years earlier than mine. Bought on E-bay with the fuel rail. Rail and FI's were identical except the wiring harness was slightly different. think the rating is 18 lbs but 19 will do okay.

On the stumble prob, you should check you Fuel Pressure with a gauge. should be 45-50 psi.
 

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1993 sedan Deville
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15 Posts
Discussion Starter #3
Thank you!!
I will try this later today and I will post what the out come was. I was hoping the miss or stumple was the one injector that was not working. I will check the FP.

Mike
 

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1993 sedan Deville
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Discussion Starter #4
All fixed ! The ecm or drivers for the fuel injectors where the problem. # 3 injector was the main cause. Put a new ecm in and ran like a kitten.I did change the o2 ,ac plugs wires and rotor and cap first.But after the ecm was changed I took it for a e test and it pasted will all zero's and 0.1 on HC. I just wanted to finish the thread with the results. (I cant stand when I read a thread and never know what the out come was)

Thanks to all for the help. Gave the car to my dad today and he loves it.
 
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