Problems with Lumina ECM replacement

First, I have to mention that my mechanic replaced my fuel pump 2 months a go and ever since my fuel gauge doesn't work.
Latley the car started sputtering and stalling, so I got a diagnostic
done at a GM dealership, they determined that my ECM was faulty. So I could not afford the kind of coin that they wanted so I had to depend on the mechanic at work. Here is the problem
Since the ECM has been replaced the car
* does not stall or sputter any more :)
* now my speedometer doesn't work :( * Seems like the car is starting in second gear :( * The inside of the car smells like gas fumes :( * The gas gauge still don't work
Can I please get some good advice. I want to know if you can program the ECM wrong, or install the wrong one etc... Or does my mechanic need to reread his repair manuals.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Speedo not working points to a possible speed sensor problem in the trans, of course mentioning year of car would help, but this would cause the trans to start in default. Scan it and see if the pcm see a sensor input. If the fuel gage worked before the pump repair something was left loose or something was done affecting the tank gage. Look for the fuel leaks!

-
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Sorry, The car is a 1993 3.1 ltr with 4 speed overdrive. Did I mention that the speedometer was working before the ECM replacement. I personally think that the mechanic made a mistake. Are both these gauges controlled by the ECM?
I long for the days of having a car without all of this computer stuff. I love technology, but not in cars :)
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Fuel tank is by itself as for the gage, pcm controls trans shifts and sends a signal to the speedo for speed readings, but the speed sensor in the trans sends the main signal to the pcm. Check all the connections at the pcm first. Any check engine lite on, should be with the speedo problem.

-
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
yes the check engine light is on
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Get the code, this may well steer you in the right direction.

-
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
I just went for a drive and noticed that when I turn on my key the speedometer jumps a little so I guess that it atleast has power.
BTW. Thanks for the help so far
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Normal on these cars even if no signal from the pcm, keep going, get the code.

-
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Motorsforum.com is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here. All logos and trade names are the property of their respective owners.