Van was sitting for 2 months, was running when parked. The fuel pump won't prime or kick in. The relay was changed and pins # 30, 85, 87, and 86 all do what they are supposed to but still no connection to fuel pump! Can someone please help? Thank you. Oh the pump is new and working for 8 months!
If the pump is getting power then I'd change the pump
Testimonial: "Good morning sir and thank you for your answer it’s greatly appreciate it so you’re saying if it is getting power I should change the pump I was thinking maybe change the ECM give me your thoughts again thank you sir"
And yes sir it will start up and run for approximately 10 seconds and shut off so for me something is shutting that fuel pump off especially after pins 86 check for ground 87 check for power constant 85 does send a code and 30 jumped it does start to fuel pump But in this scenario the pump does not prime or does not run
If the pump is receiving power then there is nothing wrong with the ECM, if the pump isn't getting power I'd check through the wiring/fuses etc for any faults before changing other parts
still not told ENGINE size, of 7 options new.
ok you said pin 87 is 12vdc on cranked engine dead.
IF 12VDC HERE ,SAME 12VDC IS IS BOTH SIDES OF FUSE24
AND IF OTHER SIDE IS NOT 12V BUT NEAR ZERO THE FUSE IS BLOWN. (WE TEST CRANKING) NOT THE SILLY 1 SECOND PRIME PULSE.
if yes AND YES, and pump pressure is dead,
then the pump is dead.
or wires from 87 + FUSE to pump are bad
wires to 87 connectors, to pump this line rustY connections.
the ECU is working if 87 says 12vdc all the time
CRANKED AT FUSE 24 TOO GEE I'D FUSE 24 TEST FIRST.
the relay an pump are just 2 simple parts and a wire
the pump ground must also happen AND A FUSE.
here it is, 4.3L super super simple wiring,
the ECM logic is not simple, (it cuts fuel for many reasons) and I told it first post.
is the IMMO lamp glowing wrong,
fuse 24 not blown
test the system cranking. a dead engine
or learn to use a scan tool.
NOTE HOW TO FUSE IS AFTER THE RELAY
KEEP THAT IN MIND, AND FUSE HAS NO RUST OR MICRO SIZED CRANKS AND IS 0 OHMS IN HAND USING DMM R1 SCALE.
MY GUESS YOU FIX CARS WITH NO SCAN TOOL
AND THE POOR ECU IS TRYING SO HARD TO TELL YOU WHY IT FAILS AND YOU DO NOT LOOK.
GOOD LUCK WITH THAT.
OP TELL WHAT THE IMMO LAMP DOES, EXACTY (DETAILS)]https://my.cardone.com/techdocs/PT%2077-...
THE PUMP SIDE IS SIMPLE, i GUESS FUSE 24 IS BLOWN AND NOT EVER CHECKED. ?
OR YOU LOST YOUR SCANTOOL OR IMMO CLASS KEY IS BAD.
OR THE WRONG PUMP WAS INSTALLED AND BLEW THE FUSE
THE GROUNDS ARE BAD SEEN ABOVE.
CHECK VOLTAGE AT THE FUSE 24 CRANKING DEAD ENGINE
BUT ENDS OF THE FUSE. 10-11VDC IS PAR WITH HEAVY STARTER CURRENTS FLOWING AND 2VDC DROP BELOW 12V.
KEEP BATTERY CHARGED AT ALL TIMES TESTING OR ALL FALLS DOWN.
ALSO NEVER RUN THE FUEL PUMP WITH DRY TANK
THE PUMP IS FUEL LUBRICATED AN FUEL COOLED BOTH.
DOING SO WRECKS IT.
http://www.chevroletproblems.com/passloc...
READ THIS, PASSLOCK ISSUES. 1995.5 FIRST ONE EVER.
AND IS MAGNETIC SIGNATURE TECH.(key slow hall sensoro)
NOTHING NEW HERE, GM HAS THEM FOR 30 + YEAR.
"If the values do not match, the fuel supply is shut off. After three consecutive failed attempts, PASSLock will enter Long Tamper Mode, disabling the engine for 10 minutes while the Theft System indicator on the instrument panel flashes. "
SO seems like a reLearn but is really Tamper punishment mode. (some cars, newer brick the PCM/BCM after 7 tries to hack IMMO) so before messing about learn all tricks your IMMO has or go broke fast.
THAT 10MIN RULE (MINUTES) IS A RELEARN RESET.hah.
90'S ERA.
FINDING 97 USERS GUIDE ARE NOT EASY NOw, THAT TELLS HOW ALL ERROR LAMPS ON THE DASH OR FOR SURE IMMO PASSLOCK (lamp colors or blink codes)
NEVER LET THE BATTERY DISCHARGE LOW OR IMMO MODULES FAIL. OR MORE.
YES THERE HACKS BACK THEN BUT ARE TRICKY.
more quotes just reading how passlock works.or does not 1997 era
the PASSLock system is designed such that forced rotation normally damages the electronics, immobilizing the vehicle. According to General Motors, should the ignition lock be force rotated, the lock must be replaced in order to operate the vehicle.
Note: The theft deterrent function of the PASSLock System locks out the fuel injectors after the engine is started. However, before a tamper mode engages, the car may run for a few seconds. The engine will then stall.
learn to read the IMMO lamp correctly or go now where fast. or even make it worse.. easy./
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Question edited heavily for clarity.
Question moved to model category.
After it was sitting, did the battery go flat, or did you have to remove it to charge it? Immobilizer and anti-theft system reset needed?
Other help in the link
https://www.google.com/search?q=1997+Chevy+Express+1500+fuel+pump+issues
..
Testimonial: "Yes as a matter fact the battery did go dead and yes I did charge it in vehicle but can you tell me more about resetting the immobilizer"
Details here
https://www.google.com/search?q=1997+Che...
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so you finally looked at the dash and the iMMO lamp is angry, causing all these problems.
lost the users glove box guide it tells you what to do.
but was never digitized to PDF in 1997 so rare it is.
fuse 24 blown
or PASSLOCK (immo) is telling you the key is bad
or is telling you needs to be reset, 10min rule.
never have just one good key on any IMMO opted cars.
or you land here, with all symptoms you told.
the key uses magnetic signatures. ( not resistors ,and not , RF signals at all) it is very different and most this old are failing.
OP A LOW BATTERY WILL CAUSE ALL COMPUTERS TO FAIL
PAGE ONE IN THE SERVICE MANUAL TELLS KEEP IT CHARGED.
FOR THIS #1 REASON.
HOW THE IMMO CUTS FUEL ON 7 ENGINES IS NOT DEFINED!!!
ONLY THAT IT DOES AND IF THE IMMO IS ANGRY LAMP IT SURE DID AND NOBODY EVER WONDERS WHY OR HOW.
ONLY HOW TO FIX IMMO MATTERS, IF TRUE.
SOME IMMO FOR SURE CUTS FUEL AT 3 TO 10 SECONDS RUNNING
THE SERVICE, MANUAL TELLS WHY.
OT GET THE CAR OUT OF TROUBLE TO TOW IT IS WHY.
SAY TIRES CURBED, OR?
LEARN THAT FIRST.
DONT LET THE 10 SECONDS FOOL YOU, LEARN TO WATCH THE IMMO LAMP AS THE USERS GUIDE TOLD YOU.
GOOD LUCK FINDING THIS.
Thanks Larry
Great advice as always. Have you seen answers by our 'new boy' Roger R? His answers are bad at best, all guesswork and no research. I delete a lot of them, but this one is golden, so I left it. It may make you smile :>)
https://www.fixya.com/support/t29900628-...
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The key has magnetic code
the key can even be bad or MARGINAL (means intermittent)
or the sensor is bad.or intermittent.
or someone forced the key and GM has forced key defeat feature.
focus like a laser beam on IMMO lamp, it does not lie to you.
yes fails often 25 years old (google see vast 97 fail ,reality)
yes 10second run means IMMO shut it down
and if super luckY( 25year parts) the IMMO lets you do the 10min key insertion trick (accessory keyed on) and it allows car to run
then fails later.
in the end new key and new key lock sensor must be replaced.
or just new key made.
never have just one key for any owned car, that is never fun.
Andrew, it has nothing to do with immobilizer (anti-theft) system . These systems do not disable the starter or the fuel pump from working .
When the VCM/PCM receives the correct code the VCM/PCM allows the fuel injectors to operate normally.
If it were a problem with the passlock™ system the vehicle would start an run for at least a couple seconds.
Vehicle Theft Deterrent (VTD) Operation (Domestic)
The design of the passlock™ system is to prevent the vehicle operation if the proper ignition key is not used in order to start the vehicle. The mechanical key, in normal operation, will turn the lock cylinder around the Passlock™ sensor. The passlock™ sensor will relay the passlock™ data to the EVO/Passlock™ module. The EVO/Passlock™ module will determine the validity of the passlock™ data. The EVO/Passlock™ module will send a password to the Vehicle/Powertrain Control Module (VCM/PCM). When the VCM/PCM receives the correct code the VCM/PCM allows the fuel injectors to operate normally. The passlock™ system requires the VCM/PCM and the EVO/Passlock™ module to communicate the various functions in order to operate. These functions transmit over the class 2 serial data line CKT 1807. For an explanation of the class 2 serial data operation refer to Data Link Connector Circuit Description in Wiring Systems
If the fuel pump isn't turning on it has a bad pump ,electrical wiring issue ,the PCM isn't commanding it on . An how do you know it's not working ? Just because you can't hear it ? Put a fuel pressure gage on it an test it ?
You don't say what engine - gas or diesel size > This vehicle comes with several different ones .
Engine Controls - 4.3L
Engine Controls - 5.0L and 5.7L
Engine Controls - 6.5L
Engine Controls - 7.4L
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NO COUNTRY TOLD
FUSE NOT TESTED FIRST, FUSE 24 MUST NOT BE BLOWN EVER
NO ENGINE TOLD OF 7 (GAS AND DIESEL BOTH)
NO VIN# NUMBER TOLD
FUEL PRESSURE CRANKING NOT TOLD ( A TOOL)
VOLTAGE AT FP RELAY 87 NOT TOLD 12VDC IS GOOD.
IMMO LAMP ACTIONS NOT TOLD AND IT DOES CUT FUEL FOR SURE IF LAMP ANY FLASHING WRONG, HOW IT CUTS FUEL I COULDN'T CARE LESS. (FIX immo IF immo NOT HAPPY)
https://my.cardone.com/techdocs/PT%2077-...
ECU NOT SCANNED AT ALL TO SEE WHY ECU WILL NOT TURN ON
THE FUEL PUMP RELAY CRANKED.
FUSE 24 IS AFTER THE RELAY THAT BLOWN MAKES PIN 87 USELESS AND ALL BEHIND IT USELESS.
FUSE 24 MUST NOT BE BLOWN;
ANSWERING FOR SPEC. USA 4.3l ENGINE SORRY NOT ANSWERING FOR 7 ENGINES ME NOR 20+ ECM'S USED WORLD WIDE I'VE NEVER SEEN;
SORRY.
PASSLOCK KEYS
https://my.cardone.com/techdocs/PT%2077-...
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