Oil Pressure Sending Switch Or Bad Fuel Pump Relay??? HELP! :(
#1
Junior Member
Thread Starter
Join Date: Aug 2010
Location: Wilmington, Caliofrnia
Posts: 36
Likes: 0
Received 0 Likes
on
0 Posts
Car: 82 Z28 .... 74 Nova
Engine: 350 Crossfire Injection....383 Sbc
Transmission: th350 ... 700r4
Axle/Gears: 2:73 Posi ... 3:42 Posi
Oil Pressure Sending Switch Or Bad Fuel Pump Relay??? HELP! :(
Well i had this problem since i got the car like 2 months ago. 82 crossfire z28
the car has a new engine and all, it runs great but it takes about 10 seconds of cranking for it to start.. and wen i turn the ignition key on, i don't hear the fuel pump buzzing.. what could it be?? Also The Oil Pressure Is Always At The Limit.. Wont Go Down At All Even Wen the car Is Off...the fuel pump is also new so thats not the problem.
Has Anyone Had This Problem Before??
The Car Runs Great But It Takes A While To Start..
the car has a new engine and all, it runs great but it takes about 10 seconds of cranking for it to start.. and wen i turn the ignition key on, i don't hear the fuel pump buzzing.. what could it be?? Also The Oil Pressure Is Always At The Limit.. Wont Go Down At All Even Wen the car Is Off...the fuel pump is also new so thats not the problem.
Has Anyone Had This Problem Before??
The Car Runs Great But It Takes A While To Start..
#2
Senior Member
iTrader: (2)
Join Date: Dec 2004
Location: Orlando,FL
Posts: 682
Likes: 0
Received 1 Like
on
1 Post
Car: 1987 GTA Trans Am
Engine: 350 TPI
Transmission: 700R4
Axle/Gears: Borg Warner 9-Bolt 3.27
Re: Oil Pressure Sending Switch Or Bad Fuel Pump Relay??? HELP! :(
Are you getting any service codes from the car or tried pulling any? As far as the oil sending unit, could have gone bad or it's not hook up.
#3
Supreme Member
Join Date: Jan 2009
Location: belle fourche,s.d.
Posts: 2,225
Received 88 Likes
on
77 Posts
Car: '82 z28
Engine: L83 5.7
Transmission: 700r4-1985
Axle/Gears: 3.42 posi
Re: Oil Pressure Sending Switch Or Bad Fuel Pump Relay??? HELP! :(
Does sound like a bad fuel pump relay or a wiring
problem..The oil pressure gauge problem is probably
the sender but could a bad connection somewhere.
My C/F setup is slightly different from stock,but IIRC
on a stock C/F,the fuel pump relay is over by the brake
booster-if you can find a wiring diagram(the one in the
hanes manual is decent)you can check that the circuits
to the relay are intact and if the relay completes the
circuit when it is energized
problem..The oil pressure gauge problem is probably
the sender but could a bad connection somewhere.
My C/F setup is slightly different from stock,but IIRC
on a stock C/F,the fuel pump relay is over by the brake
booster-if you can find a wiring diagram(the one in the
hanes manual is decent)you can check that the circuits
to the relay are intact and if the relay completes the
circuit when it is energized
#4
Supreme Member
Join Date: Sep 2002
Location: Cary, North Carolina
Posts: 9,192
Likes: 0
Received 16 Likes
on
16 Posts
Car: 1992 RS
Engine: Carbed 350
Transmission: 700R4
Axle/Gears: 3.42 posi
Re: Oil Pressure Sending Switch Or Bad Fuel Pump Relay??? HELP! :(
Not an expert on CF, but does sound like a fuel pump relay issue.
Usually, as I understand it, the ECM controls fuel pump through the relay. IF that fails, then the OPSU will run the fuel pump, but it takes a few seconds to get car started, since the oil pressure has to build enough to get fuel pump triggered on, and then time to get fuel pressurized to the injectors.
Some of the early 3rd gens had 2 seperate oil pressure units, 1 for the guage, one for the fuel pump. They are either located on the china wall on driver side of dist, or above oil filter (or both locations maybe if it's a 2 unit car).
Here's wiring diags for just about everything: http://www.austinthirdgen.org/index.php?pid=19
Usually, as I understand it, the ECM controls fuel pump through the relay. IF that fails, then the OPSU will run the fuel pump, but it takes a few seconds to get car started, since the oil pressure has to build enough to get fuel pump triggered on, and then time to get fuel pressurized to the injectors.
Some of the early 3rd gens had 2 seperate oil pressure units, 1 for the guage, one for the fuel pump. They are either located on the china wall on driver side of dist, or above oil filter (or both locations maybe if it's a 2 unit car).
Here's wiring diags for just about everything: http://www.austinthirdgen.org/index.php?pid=19
#5
Junior Member
Thread Starter
Join Date: Aug 2010
Location: Wilmington, Caliofrnia
Posts: 36
Likes: 0
Received 0 Likes
on
0 Posts
Car: 82 Z28 .... 74 Nova
Engine: 350 Crossfire Injection....383 Sbc
Transmission: th350 ... 700r4
Axle/Gears: 2:73 Posi ... 3:42 Posi
Re: Oil Pressure Sending Switch Or Bad Fuel Pump Relay??? HELP! :(
Well i found the problem :O
yes it was a bad Fuel Pump Relay
i got a new one for 15 dollars at the dealer and it works fine now
thank u guys for the help
yes it was a bad Fuel Pump Relay
i got a new one for 15 dollars at the dealer and it works fine now
thank u guys for the help
Last edited by Antlocks; 09-19-2010 at 11:37 PM.
Thread
Thread Starter
Forum
Replies
Last Post
92camaroJoe
Tech / General Engine
6
08-13-2015 06:07 AM