View Full Version : 94 eldo tc engine knocking (i think)

08-25-06, 10:30 AM
hey i have a 94' Eldo and this past week i have started to hear a knocking and my mechanic said its in the motor. He said it is not a problem b/c he has heard it b4 with the N* motors and nothing has happened, but i have had my car for 1and1/2 years and it has NEVER made a noise like this. One thing that has happened in the past month is that the car has been SURGING and to keep stopped at a light is CRAZY i don't know if this has caused it. i also had changed the egr and once i found it was not that i put the old one back on and later that night the car was smoking but after that night no more smoke. With the knocking it sounds like a rattling and it does not do it all the time but when i am driving and the windows are down i can hear it out of both sides idk if i should go to the dealer and have them look at it and it is the BOTTOM of the motor PLEASE HELP i don't want to sell my caddy!:confused:

08-25-06, 02:00 PM
First of all :welcome: to the forums! :wave:

The rattling is most likely from the tranny. I have it on my 94 eldo also, mostly while accellerating up inclines. Although I do not know exactly what is causing it, nothing bad has developed in the year or so that I've had the problem.

Your surging sounds a lot like a bad FPR (Fuel Pressure Regulator), you should check it to see if any gas is leaking out of it.

08-25-06, 03:52 PM
Do a search for "carbon". If you baby your car, that's likely the problem.

08-26-06, 03:57 PM
i know 4.9's when they have this problem its the egr or clogged throttle body tubes.
Since you said replacing the egr didnt help would cleaning the TB be a logical solution?

08-26-06, 11:40 PM
No code?

08-27-06, 07:49 PM
i think it might be the cat , i know if it breaks up inside the screen starts rattling around inside.

Elmer Fudd
08-27-06, 08:51 PM
i think it might be the cat , i know if it breaks up inside the screen starts rattling around inside.

The cat is a possibility. My 86 town car had the honey comb (or whatever you call it) come loose in one of the cats. It rattled and "donged" around in there, I was sure it was engine noise, sounded just like a lower engine knock.
When I found it I tried to ignore it :rant2: .....that lasted about a week....then I cut the dam thing off.....:rolleyes:

08-27-06, 10:12 PM
There is a knock that comes from the lower end that is caused by a combination of the tension of the serpentine belt and clearance in the front main bearing. Troubleshooting is done by temporarily removing the serpentine belt and see if the noise goes away. This noise is harmless but there is a substitute front main bearing available if it really bugs you.