93 Deville Running Rough (Part2)

Today I looked the codes that are coming up on my moms car and they are the following E27 Open Throttle Switch Signal, E40 Open Power Steering Preasure Switch Signal, E48 EGR System Problem, E90 VCC Brake Switch Signal Problem. now there are also the following that came up .7.0 and .E.E I dont know what those are, of the Error codes that came up can someone explain to me what is needed to repair each one. Thanks for all that can and has helped. Kraig

for the the following codes E27 you have a problem with your throttle body, which could be causing bad air gas mixture, For E40 Its a power steering problem, bad pressure, get that checked, for E48 its Exhaust Gas Recirculation (EGR) system Problem which means somethings up with ur exhaust, it cant get around they way it should, get that looked at, and E90 has to do with your transmission, according to the codes i found, VCC/TCC Brake Switch/Park/neutral switch Input Circuit Problem, could be causing your car to react differently to the transmission. i'll look for those other codes later and let you know.

Thanks for the replys her SES light has been on for quite some time, When you first put the car into gear from park or a stop you really have to push down on the gas for it to go almost like the trans slipping she had that looked at last year and the mechanic replaced a fuse and it was fine for a few weeks but it is back to where it was. her car I noticed is averaging 12 miles per gallon verses my deville also a 93 at 21 mpg and at the prices of gas here 2.39 not a good thing you literally can watch the numbers drop on the gas gage!!! could the throttle body needing cleaned be the culprit. KC

cleaning could help, check inside see if something is stuck in there or isnt in there correctly, it could be causing very poor flow of air which can make it drink gas like crazy and still run like crap

Where is the throttle body located at. KC

http://www.top2bottoment.com/car/images/caddy3aof10.jpg Is that what the engine looks like, if it does it would make it easier to point it out, you can try and locate it by looking from the air filter, just follow from that all the way intil it goes into the engine, see if the filer is got something caught there and its blocking it, or if something is stuck in the tube, if you see a housing with a buterfly valve and some cables going to it, thats the throttle body

http://www.4x4wire.com/mitsubishi/tech/throttle_body/throttle_body_apart.jpg
Theres a diagram of where the throttle body may be, and wat it may look like.

I am going out to check it out it is the same. Thanks !!! KC

She took her car today and had it put on a diagnostics computer and the mechanic said that her EGR valve was bad and needed replaced is this the culprit for the bad gas mpg she also got new wires and plugs for it also. I hope this helps will cost $300.00

The EGR valves on the 4.9s rarely go bad. I'd check that it's getting good vacuum, and that the EGR tubes that are under the throttle body in the intake are clear.
If you upon the throttle blade, you can see two tubes that stick up from the bottom of the intake. Make sure those are clean and not plugged with carbon.