Cadillac Owners Forum banner

1993 Deville

1188 Views 3 Replies 4 Participants Last post by  Ranger
Could someone please help me diagnose my caddy?

Last November, I took my car in to the dealership for the following problems:
1) Vibrations when lane changing on the freeway. My guess was:(wheel bearings) They said that wasn't the problem, they state everything is fine......As of today, it still vibrates.
2) My car bogs, hesitates, backfires when I step on the gas. They replaced the ISC motor and put in a new throttle of today it still bogs, hesitates, and backfires when I step on the gas.

Anybody have any ideas. I am used to working on Fords (Merkurs), I didn't think it would be this hard for a dealership to diagnose. I'm sick of being taken to the cleaners for crap service. I've taken it in 3 times already and each time came back with the same results. Do they actually QC their work? Are there ways to read codes on Cadillacs? Any help would be much appreciated.

1 - 4 of 4 Posts
Your 93 DEV is OBD1 and has an easy to use on board diagnostic system. read the sticky on how to pull codes at the top of this forum. post the codes and the description would help. . Start there! I'm sure everyone will try to help u. I have an FSM for that year, depending on what the codes are, etc. You can get them on ebay pretty cheap. You'll be needing that if you do your own work.
I'm amazed that the dealership couldn't fix it. You don't hear of any throttle bodies going bad around here. I don't think they even tried to diagnose the problem; they just wanted to replace something easy on top of the engine. Backfires are caused by ignition problems 95% of the time. When was the last tune up?
Yeah, start with plugs, wires, cap & rotor. Look down the TB. See the two EGR tubes staring back at you? Make sure they are open. If they are carboned closed, rod them out.

Vibration is likely a wheel balance or tie rod or such. Have a good front end shop look it over.
1 - 4 of 4 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.