New fuel pump has power but wont pump
#1
Member
Thread Starter
Join Date: Mar 2013
Posts: 121
Likes: 0
Received 0 Likes
on
0 Posts
Car: 1989 Formula
Engine: 305
Transmission: T-5
Axle/Gears: 3.45 1LE Disc LSD
New fuel pump has power but wont pump
Hey guys i have just about finished my restoration on my 1985 iroc and today was suppose to be the day to start her for the first time.
The fuel pump in the tank right now is brand new never used. So is the sending unit, strainer and filter. I cleaned the lines out so i already no there is no blockage in the lines.
I also tested the pump before installing it and it worked fine.
So at this moment the engine is complete besides an alternator but i wanted to crank this motor over today.
I tested the power at the pump under the car and it is getting power. But it is not pumping fuel at all.
I disconnected the oil/fuel pressure sensor and that did nothing.
Any help would be awesome thank guys.
The fuel pump in the tank right now is brand new never used. So is the sending unit, strainer and filter. I cleaned the lines out so i already no there is no blockage in the lines.
I also tested the pump before installing it and it worked fine.
So at this moment the engine is complete besides an alternator but i wanted to crank this motor over today.
I tested the power at the pump under the car and it is getting power. But it is not pumping fuel at all.
I disconnected the oil/fuel pressure sensor and that did nothing.
Any help would be awesome thank guys.
#2
Member
Thread Starter
Join Date: Mar 2013
Posts: 121
Likes: 0
Received 0 Likes
on
0 Posts
Car: 1989 Formula
Engine: 305
Transmission: T-5
Axle/Gears: 3.45 1LE Disc LSD
Re: New fuel pump has power but wont pump
Ill drop the tank and recheck everything is no one can think of anything else.
#3
Senior Member
iTrader: (8)
Join Date: Aug 2011
Location: Texas
Posts: 661
Likes: 0
Received 6 Likes
on
6 Posts
Car: 91 Firebird/88 Firebird/91 Formula
Engine: V6 3.1/V8 5.0/V8 5.0
Transmission: 4L60/700R4/4L60
Axle/Gears: 3.23/2.73/2.73
Re: New fuel pump has power but wont pump
Do you hear the fuel pump prime at all? Check the fuse in the fender well and the fuel pump relay?
#4
Member
Thread Starter
Join Date: Mar 2013
Posts: 121
Likes: 0
Received 0 Likes
on
0 Posts
Car: 1989 Formula
Engine: 305
Transmission: T-5
Axle/Gears: 3.45 1LE Disc LSD
Re: New fuel pump has power but wont pump
there is not any priming noise and im not getting any power at the relay. Which is weird bc i thought there had to be power at the relay to have power at the pump. I do not think there is an inline fuse on an 85 harness. Just the one under the dash which is ok.
#5
Senior Member
iTrader: (8)
Join Date: Aug 2011
Location: Texas
Posts: 661
Likes: 0
Received 6 Likes
on
6 Posts
Car: 91 Firebird/88 Firebird/91 Formula
Engine: V6 3.1/V8 5.0/V8 5.0
Transmission: 4L60/700R4/4L60
Axle/Gears: 3.23/2.73/2.73
Re: New fuel pump has power but wont pump
No use dropping the tank if you're not getting power at the relay. The problem should be power line before the relay. Apply 12v to the harness at the relay to the pump and see if it primes.
#6
Member
Thread Starter
Join Date: Mar 2013
Posts: 121
Likes: 0
Received 0 Likes
on
0 Posts
Car: 1989 Formula
Engine: 305
Transmission: T-5
Axle/Gears: 3.45 1LE Disc LSD
Re: New fuel pump has power but wont pump
ok im gonna try that im also thinking the problem might be a bad ground under the dash to the junction box. ill be looking hard
#7
Re: New fuel pump has power but wont pump
Even with the power off, make sure your frame has ground from the battery to it with an ohm meter, don't use a light since if it has a poor connection the light may still be on.
Should read zero ohms, and check one side of that relay, it should also read zero ohms, what does it read with the key off
Should read zero ohms, and check one side of that relay, it should also read zero ohms, what does it read with the key off
Trending Topics
#8
Member
Thread Starter
Join Date: Mar 2013
Posts: 121
Likes: 0
Received 0 Likes
on
0 Posts
Car: 1989 Formula
Engine: 305
Transmission: T-5
Axle/Gears: 3.45 1LE Disc LSD
Re: New fuel pump has power but wont pump
Even with the power off, make sure your frame has ground from the battery to it with an ohm meter, don't use a light since if it has a poor connection the light may still be on.
Should read zero ohms, and check one side of that relay, it should also read zero ohms, what does it read with the key off
Should read zero ohms, and check one side of that relay, it should also read zero ohms, what does it read with the key off
#9
Re: New fuel pump has power but wont pump
http://www.harborfreight.com/7-funct...ter-98025.html
#10
Member
Thread Starter
Join Date: Mar 2013
Posts: 121
Likes: 0
Received 0 Likes
on
0 Posts
Car: 1989 Formula
Engine: 305
Transmission: T-5
Axle/Gears: 3.45 1LE Disc LSD
Re: New fuel pump has power but wont pump
Buy one from here, and quickly fix it, I'm in electronics not a mech., your issue is electrical not something else, rust and water are your issue in the end. So buy one, and I will walk you through, if you need more help
http://www.harborfreight.com/7-funct...ter-98025.html
http://www.harborfreight.com/7-funct...ter-98025.html
#11
Re: New fuel pump has power but wont pump
Doing the electric part is the easy part, worse issue, we find a wiring diagram of your car, and we fix it!!! Don't sweat the very small stuff I just joined here only to try to find out what my buddy's car is worth, but I saw your post and I love fixing things so if anyone else here needs my help with a weird electrical issue try me, I like a good challenge
Gary
Gary
#12
Member
Thread Starter
Join Date: Mar 2013
Posts: 121
Likes: 0
Received 0 Likes
on
0 Posts
Car: 1989 Formula
Engine: 305
Transmission: T-5
Axle/Gears: 3.45 1LE Disc LSD
Re: New fuel pump has power but wont pump
ok i hooked up a power line directly to my fan relay power line and that gave the fuel pump relay power and now my fuel pump works.
Unfortunately im not getting spark.
As of now i have a power wire hooked up directly to my starter, alt., and fan relay power wire. Where do i need to place power to get power to the distributor is the new question. I dont have a factory positive cable and i think that why im having problems.
Unfortunately im not getting spark.
As of now i have a power wire hooked up directly to my starter, alt., and fan relay power wire. Where do i need to place power to get power to the distributor is the new question. I dont have a factory positive cable and i think that why im having problems.
#13
Re: New fuel pump has power but wont pump
ok i hooked up a power line directly to my fan relay power line and that gave the fuel pump relay power and now my fuel pump works.
Unfortunately im not getting spark.
As of now i have a power wire hooked up directly to my starter, alt., and fan relay power wire. Where do i need to place power to get power to the distributor is the new question. I dont have a factory positive cable and i think that why im having problems.
Unfortunately im not getting spark.
As of now i have a power wire hooked up directly to my starter, alt., and fan relay power wire. Where do i need to place power to get power to the distributor is the new question. I dont have a factory positive cable and i think that why im having problems.
#14
Re: New fuel pump has power but wont pump
Pick yours out from this link, and post the url link here, I will hold your hand so you get a spark ASAP BUT BUY THE METER it makes thing so much easier, plus it's so easy to use, your dog can even test with it, what no dog sorry LOL
https://www.google.com/search?q=1985...=isch&imgdii=_
https://www.google.com/search?q=1985...=isch&imgdii=_
#15
Re: New fuel pump has power but wont pump
Unless you have a12 volt light bulb with two wires on it, we can't do too much, but I'm sure, you must have an old light bulb and socket kicking around with the wires still on the socket
Does this car use a control module? If so you got to check if it's getting power, because that would explain the fuel pump issue or it's been disabled, it maybe looking for another signal from a sensor, telling it to shut down, or even it could be bad!!!!
Does this car use a control module? If so you got to check if it's getting power, because that would explain the fuel pump issue or it's been disabled, it maybe looking for another signal from a sensor, telling it to shut down, or even it could be bad!!!!
#16
Member
Thread Starter
Join Date: Mar 2013
Posts: 121
Likes: 0
Received 0 Likes
on
0 Posts
Car: 1989 Formula
Engine: 305
Transmission: T-5
Axle/Gears: 3.45 1LE Disc LSD
Re: New fuel pump has power but wont pump
I figured out part of my spark problem there was a bent tooth from the the harness to the coil. Fixed that now i have power up to my two wire plug into the control module but i have no power coming out the control module.
#17
Re: New fuel pump has power but wont pump
Is yours a carb or fuel injection model? Do you have the light bulb? How did you measure YOU have power going into the control module?
#19
Re: New fuel pump has power but wont pump
The control module has more than one hot input, which diagram is yours the one i'm looking at is this one, but I'm not sure it's even close to your car
It will not give power out, unless all the hot inputs are there
It will not give power out, unless all the hot inputs are there
Last edited by garydiamond; 07-05-2014 at 10:42 PM.
#21
Member
Thread Starter
Join Date: Mar 2013
Posts: 121
Likes: 0
Received 0 Likes
on
0 Posts
Car: 1989 Formula
Engine: 305
Transmission: T-5
Axle/Gears: 3.45 1LE Disc LSD
Re: New fuel pump has power but wont pump
Ok thanks for your help man i figured out the problem. I had a bad connection with my coil to module harness. It is brand new but i guess any pos can be sold through ebay. Thanks again hopefully this car will start real soon.
#22
Re: New fuel pump has power but wont pump
#23
Re: New fuel pump has power but wont pump
Hi guys! I got a similiar issue.... I got spark, and power EVERYWHERE, EXCEPT to the FUEL PUMP... IF I CUT the GREY WIRE and connect a FUSED DC power cable to the GREY WIRE and a GROUND WIRE, DIRECT to the BLACK wire... I GOT to have power to the pump, CORRECT? I THINK I have a failed ECM... I have power under the hood, at ALL POINTS of the fuel system, but from the FIREWALL to REAR BULKHEAD, I got NO POWER TO THE PUMP... Car is original, 90 K on it.. Been sitting but run every few weeks, and moved around the yard... Gave it to my daughter as a Graduation gift, and now want to let her run it, and THIS happens.. AAARRGFGHH! Owned it for 12 years and only put 3000 miles on her, with NEVER an issue and it died in the front yard as I was going to take it to put tires on it... Can not win...
#24
Re: New fuel pump has power but wont pump
Can you find a wiring diagram online, so we can check to see if the ECM is happy one of the end puts could be wrong, because of a sensor, or signal missing, giving the wrong info, that would cause the voltage to the pump to be missing
#25
Member
Thread Starter
Join Date: Mar 2013
Posts: 121
Likes: 0
Received 0 Likes
on
0 Posts
Car: 1989 Formula
Engine: 305
Transmission: T-5
Axle/Gears: 3.45 1LE Disc LSD
Re: New fuel pump has power but wont pump
Hi guys! I got a similiar issue.... I got spark, and power EVERYWHERE, EXCEPT to the FUEL PUMP... IF I CUT the GREY WIRE and connect a FUSED DC power cable to the GREY WIRE and a GROUND WIRE, DIRECT to the BLACK wire... I GOT to have power to the pump, CORRECT? I THINK I have a failed ECM... I have power under the hood, at ALL POINTS of the fuel system, but from the FIREWALL to REAR BULKHEAD, I got NO POWER TO THE PUMP... Car is original, 90 K on it.. Been sitting but run every few weeks, and moved around the yard... Gave it to my daughter as a Graduation gift, and now want to let her run it, and THIS happens.. AAARRGFGHH! Owned it for 12 years and only put 3000 miles on her, with NEVER an issue and it died in the front yard as I was going to take it to put tires on it... Can not win...
Thread
Thread Starter
Forum
Replies
Last Post
theshackle
Tech / General Engine
4
03-05-2017 06:37 PM
92camaroJoe
Tech / General Engine
6
08-13-2015 06:07 AM