Jeep: Problem with 91 comanche

I have this problem with my 91 comanche 2.5L. The engine rotates but will
not start. I hooked up a spark tester and noticed no spark from any line
and replaced ignition coil, but still no spark. The book says that it could
be The ECU (engine control unit)since there is no control moduale on my
year. My question is, where is this ECU located and bout how much will it
cost me to replace it? I also notice on the key on, key off code retriever
does not work anymore. It also mentions that the ECU and PCM are one and
the same. Will appreciate any advice.

Edwin T.

"E.T." <net> wrote in message
news:1xgu3r9yzmejv$net... 
will 
could 
it 
retriever 

Hi Ed,


I don't know if thi is thje same problem, but I will tell you what I
experienced, with a 93 Cherokee,

At first It would crank and crank but would not start for 15 to 30 seconds.
Then I realized something, that the fuel pump was not coming on for 15 to
30 seconds, So I would wait until, I heard the whirring noise of the fuel
pump before cranking, and then it would start.

I also observed the following, the check engine light would not come on
until the fuel pump came on. Also I took it back to the place I bought it,
supposedly under warranty. And they said they could not get spark or read
the codes from the PCM. They were convinced it was the crankshaft sensor a
common problem with jeeps, or fuel pump. But I had found 1 article on the
interent experiencing a similar problem and it turned out to be a bad
capacitor in the ECM, once that was replaced (twice !! the entire ecm) it
runs fine now.

also possible culprit is the Security system, or wiring asscosiated with
the ecm gone bad.

Good luck Ed.