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CHRIS ZAPANTIS
CHRIS ZAPANTIS,
Category: Mercury
Satisfied Customers: 159
Experience:  AUTO TECH at G&M EXXON
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Mercury Grand Marquis: 97 GRAND MARQUIS-CRANKS NO START--NO

Customer Question

97 GRAND MARQUIS-CRANKS NO START--NO CHECK ENGINE LIGHT, HAVE POWER TO INJECTORS AND COILS
Submitted: 7 months ago.
Category: Mercury
Expert:  CHRIS ZAPANTIS replied 7 months ago.
Hello I'm chris and I can assist you. Did you check for fuel pressure?
Customer: replied 7 months ago.
fuel not issue. no spark, no injector pulse, no check engine light
Customer: replied 7 months ago.
have power to coils, injectors, mass air flow sensor. power to pins 55, 71, 97 at ecm
grounds good at pins 25, 25, 51, 76, 77, 103
Customer: replied 7 months ago.
meant 24 and 25
Expert:  CHRIS ZAPANTIS replied 7 months ago.
Ok before I go any further how do you know that the fuel is no issue?
Expert:  CHRIS ZAPANTIS replied 7 months ago.
sorry I misread
Expert:  CHRIS ZAPANTIS replied 7 months ago.
I took it as you have spark and pulse
Expert:  CHRIS ZAPANTIS replied 7 months ago.
does the CEL come on when you turn on key?
Customer: replied 7 months ago.
no check engine light
Customer: replied 7 months ago.
no spark, no injector pulse
Customer: replied 7 months ago.
crank sensor good, also not the issue
Expert:  CHRIS ZAPANTIS replied 7 months ago.
Ok. Without me getting the diagram ot I presume you have checked powers and grounds to the ecm?
Customer: replied 7 months ago.
yes with dvom
Customer: replied 7 months ago.
pins 55 71 97, all have battery voltage--pins 24 25 51 76 77 103 all have good grounds
Expert:  CHRIS ZAPANTIS replied 7 months ago.
Ok. From what you are telling me I would have to say you have a bad ECM.
Customer: replied 7 months ago.
tried 3 different ones
Customer: replied 7 months ago.
i would agree with that statement
Customer: replied 7 months ago.
but 3 ecms.....
Expert:  CHRIS ZAPANTIS replied 7 months ago.
do you have a scanner?
Customer: replied 7 months ago.
yes snap on verus and alltel--neither communicate
Expert:  CHRIS ZAPANTIS replied 7 months ago.
I guess you are in the business?
Customer: replied 7 months ago.
49 years, but sometimes you cannot see the forest for the trees are in your way
Customer: replied 7 months ago.
grounded the pink light green wire.pin 2, and the check engine light works
Expert:  CHRIS ZAPANTIS replied 7 months ago.
let me get A DIAGRM GIMME A COUPLE MIN
Customer: replied 7 months ago.
ok
Expert:  CHRIS ZAPANTIS replied 7 months ago.
is the engine a "w"?
Customer: replied 7 months ago.
yes
Expert:  CHRIS ZAPANTIS replied 7 months ago.
you checked for battery voltage at MAF?
Customer: replied 7 months ago.
battery voltage, and at coils, and at injectors
Expert:  CHRIS ZAPANTIS replied 7 months ago.
does your maf have a red wire going to it? Is there 12 volts there?
Customer: replied 7 months ago.
yes it has a red wire. battery voltage at it and at coil and at injectors
Expert:  CHRIS ZAPANTIS replied 7 months ago.
ok. You know I seen this once before like 5 years ago turned out to be the crANK sensor
Customer: replied 7 months ago.
new crank sensor
Expert:  CHRIS ZAPANTIS replied 7 months ago.
I don't remember if the cel was working though
Customer: replied 7 months ago.
also checked for ac voltage good sensor
Customer: replied 7 months ago.
did notice my 5 volt reference voltage is low. under 2 volts
Expert:  CHRIS ZAPANTIS replied 7 months ago.
di you start disconnecting tps and dpfe one at a time to see if they are pulling the voltage down?
Expert:  CHRIS ZAPANTIS replied 7 months ago.
try not start
Customer: replied 7 months ago.
disconnected both of them no change,
Customer: replied 7 months ago.
cannot get to the fuel pressure sensor
Expert:  CHRIS ZAPANTIS replied 7 months ago.
fuel pressure sensor?
Customer: replied 7 months ago.
it is also on the 5 volt reference circuit
Expert:  CHRIS ZAPANTIS replied 7 months ago.
ok
Expert:  CHRIS ZAPANTIS replied 7 months ago.
this diagram is cut into a bunch of pieces
Expert:  CHRIS ZAPANTIS replied 7 months ago.
25 51 76 77 103 you checked right?
Expert:  CHRIS ZAPANTIS replied 7 months ago.
all power?
Expert:  CHRIS ZAPANTIS replied 7 months ago.
also 55?
Customer: replied 7 months ago.
yes--55-77-97
Customer: replied 7 months ago.
even checked the body grounds g101 g102 g103
Expert:  CHRIS ZAPANTIS replied 7 months ago.
ok where weren't you getting the 5 volts reference?
Customer: replied 7 months ago.
getting it but under 2 volts
Expert:  CHRIS ZAPANTIS replied 7 months ago.
ok where?
Customer: replied 7 months ago.
at tps and dpfe, both sensors disconnected
Customer: replied 7 months ago.
both disconnected at the same time
Expert:  CHRIS ZAPANTIS replied 7 months ago.
does pin 55 have yellow/black wire?
Customer: replied 7 months ago.
yes 12 volts
Expert:  CHRIS ZAPANTIS replied 7 months ago.
pin 92 light green
Customer: replied 7 months ago.
yes--
Expert:  CHRIS ZAPANTIS replied 7 months ago.
that ecm has to be bad is it junk yard?
Customer: replied 7 months ago.
had key on with it plugged in, is hot to the touch
Customer: replied 7 months ago.
no cardone rebuilt number two, first one same thing. same as original computer
Expert:  CHRIS ZAPANTIS replied 7 months ago.
if I were you ide try a different brand or even junk yard at this point
Expert:  CHRIS ZAPANTIS replied 7 months ago.
3 months ago I had 2 Chrysler rebuilt pcm that were bad.
Expert:  CHRIS ZAPANTIS replied 7 months ago.
the fact the CEL isn't coming on bugs me
Customer: replied 7 months ago.
once in 86 had 7 ford bad ecms from ford while working for them
Customer: replied 7 months ago.
i know the cel normally would come on anyway
Expert:  CHRIS ZAPANTIS replied 7 months ago.
that's crazy
Customer: replied 7 months ago.
alway been able to communicate. but not this time
Expert:  CHRIS ZAPANTIS replied 7 months ago.
that's why I'm not going crzy with the 5 volt reference issue. if that were the problem cel would still come on
Expert:  CHRIS ZAPANTIS replied 7 months ago.
that comes directly from ecm. so the ecm is not powering it
Customer: replied 7 months ago.
ok yet another bad ecm
Customer: replied 7 months ago.
only thing i can think of
Expert:  CHRIS ZAPANTIS replied 7 months ago.
its the only thing that makes sense
Customer: replied 7 months ago.
thanks
Expert:  CHRIS ZAPANTIS replied 7 months ago.
No problem
Expert:  CHRIS ZAPANTIS replied 7 months ago.
Thank you and please rate me so I get credit. I'm going to leave this open so you can come back and let me know what happens. I'm dying to see.
Expert:  CHRIS ZAPANTIS replied 7 months ago.
Oh don't get a cardone again if they are bad they are al probably bad
Customer: replied 7 months ago.
hey chris still there
Customer: replied 7 months ago.
put the ORIGINAL COMPUTER BACK IN.
SAME THING
Customer: replied 7 months ago.
check 5 volt reference at computer and not good. cut the wire feeding 5 volt reference. 5 volts now at the computer and voila...check engine light is on
Customer: replied 7 months ago.
must have short in 5 volt reference wire somwhere.....
Customer: replied 7 months ago.
cut wire out of the computer right next to connector. maybe fuel pressure sensor.... i.ll check tomorrow
Expert:  CHRIS ZAPANTIS replied 7 months ago.
great
Expert:  CHRIS ZAPANTIS replied 7 months ago.
let me know
Expert:  CHRIS ZAPANTIS replied 7 months ago.
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