82 started last week... now doesn't
Thread Starter
Intermediate
Joined: Aug 2013
Posts: 45
Likes: 0
82 started last week... now doesn't
Last week the car started and ran fine.
Yesterday, won't start. There seems to be no power getting to the fuel pump.
The test I did last night, putting 12 volts to pin G on the ALCL, did NOT power the fuel pump as it should have. All I got was a red hot wire at the G terminal. So I'm not sure what that means, the fuel pump should have ran since its a direct connection.
I have a voltmeter, if someone can point me in the right direction for finding the problem.
What about the fuel pump relay. I'm about to pull it out. Any way to test it out of the car?
Yesterday, won't start. There seems to be no power getting to the fuel pump.
The test I did last night, putting 12 volts to pin G on the ALCL, did NOT power the fuel pump as it should have. All I got was a red hot wire at the G terminal. So I'm not sure what that means, the fuel pump should have ran since its a direct connection.
I have a voltmeter, if someone can point me in the right direction for finding the problem.
What about the fuel pump relay. I'm about to pull it out. Any way to test it out of the car?
Melting Slicks
Joined: Mar 2006
Posts: 2,248
Likes: 67
From: Warrington PA
Finalist 2020 C4 of the Year - Unmodified
ok....hope this helps......
read the "sticky" for 82 CFI owners in the tech section...here is the link....
http://forums.corvetteforum.com/c3-t...solutions.html
and I remembered a thread that duplicates your problem and here is the link.....turns out it was the fuel pump relay in this situation. Again, read the "sticky", it will give you good info for troubleshooting CFI problems and possible solutions. Start from the beginning and use the section you need, it will save you time.
Also the other 82 members are very well versed and I'm sure will offer their expertise in getting you started and running once again.
Let us know your progress......................Tom
http://forums.corvetteforum.com/c3-t...y-82-vett.html
I do not know the way to test the relay out of the car, if at all. You need the Service Manual to check, I will try to get to it sometime today, or other members may have the answer for you.....
read the "sticky" for 82 CFI owners in the tech section...here is the link....
http://forums.corvetteforum.com/c3-t...solutions.html
and I remembered a thread that duplicates your problem and here is the link.....turns out it was the fuel pump relay in this situation. Again, read the "sticky", it will give you good info for troubleshooting CFI problems and possible solutions. Start from the beginning and use the section you need, it will save you time.
Also the other 82 members are very well versed and I'm sure will offer their expertise in getting you started and running once again.
Let us know your progress......................Tom
http://forums.corvetteforum.com/c3-t...y-82-vett.html
I do not know the way to test the relay out of the car, if at all. You need the Service Manual to check, I will try to get to it sometime today, or other members may have the answer for you.....
Last edited by 74 LS4-454; Oct 6, 2013 at 11:40 AM.
Thread Starter
Intermediate
Joined: Aug 2013
Posts: 45
Likes: 0
Update:
Discovered I was using the wrong terminal on the ALCL (connector is upside down from diagrams), was using A (ground), was why it was glowing red hot.
So using the correct G terminal, which bypasses the fuel pump relay, I get NOTHING from the fuel pump. This has to mean I got a bad fuel pump, or possibly the connection inside the tank came loose. The pump is brand new just put it in yesterday.
Would anyone confirm or correct me on this?
Discovered I was using the wrong terminal on the ALCL (connector is upside down from diagrams), was using A (ground), was why it was glowing red hot.
So using the correct G terminal, which bypasses the fuel pump relay, I get NOTHING from the fuel pump. This has to mean I got a bad fuel pump, or possibly the connection inside the tank came loose. The pump is brand new just put it in yesterday.
Would anyone confirm or correct me on this?
Melting Slicks
Joined: Mar 2006
Posts: 2,248
Likes: 67
From: Warrington PA
Finalist 2020 C4 of the Year - Unmodified
Update:
Discovered I was using the wrong terminal on the ALCL (connector is upside down from diagrams), was using A (ground), was why it was glowing red hot.
So using the correct G terminal, which bypasses the fuel pump relay, I get NOTHING from the fuel pump. This has to mean I got a bad fuel pump, or possibly the connection inside the tank came loose. The pump is brand new just put it in yesterday.
Would anyone confirm or correct me on this?
Discovered I was using the wrong terminal on the ALCL (connector is upside down from diagrams), was using A (ground), was why it was glowing red hot.
So using the correct G terminal, which bypasses the fuel pump relay, I get NOTHING from the fuel pump. This has to mean I got a bad fuel pump, or possibly the connection inside the tank came loose. The pump is brand new just put it in yesterday.
Would anyone confirm or correct me on this?
You have fuel in the tank, but the pump is not running.....pull one of your spark plugs and see if you have spark. Use an old plug to insert into the plug wire and lean against the exhaust manifold shield, this way you won't get sapped......
It is also possible that you reversed the connections on the new fuel pump you installed yesterday.
BTW, did you replace with an 82 unit or an 85 TPI pump???
Thread Starter
Intermediate
Joined: Aug 2013
Posts: 45
Likes: 0
I haven't pulled a plug and checked for spark but I'm 99.9% sure its not that. There's no activity from the pump and there's no fuel coming from the injectors.
The fuse you mention is good. I don't think its possible to reverse the in-tank connection but either way I think I have to remove the pump...
I'm using a 85 pump.
The fuse you mention is good. I don't think its possible to reverse the in-tank connection but either way I think I have to remove the pump...
I'm using a 85 pump.
Intermediate
Joined: Jan 2011
Posts: 44
Likes: 0
Just my opinion,
If you are not hearing the nosie that the pump is working, I would start by checking to see if you have any power getting to the connector at the top of the tank. You can also listen to hear if the relay is clicking in by removing the storage compartment. If not, start working your way back using a wiring diagram (i.e. main fusefor FP, then relay, etc.).
I had a similar problem the other day but could hear the pump working, just not getting any fuel to the TB's. Checked and had good spark but no fuel. Everything looked good with the fuses and connections. Jumped the diagnostic connector and did not get any faults. Tried to start the car again and fired right up. Not sure what happened but the gremlin ran away.
Hope you get it running.
If you are not hearing the nosie that the pump is working, I would start by checking to see if you have any power getting to the connector at the top of the tank. You can also listen to hear if the relay is clicking in by removing the storage compartment. If not, start working your way back using a wiring diagram (i.e. main fusefor FP, then relay, etc.).
I had a similar problem the other day but could hear the pump working, just not getting any fuel to the TB's. Checked and had good spark but no fuel. Everything looked good with the fuses and connections. Jumped the diagnostic connector and did not get any faults. Tried to start the car again and fired right up. Not sure what happened but the gremlin ran away.
Hope you get it running.
Thread Starter
Intermediate
Joined: Aug 2013
Posts: 45
Likes: 0
Thank you.
The reason for the new pump was because yesterday went to start the car, crank but no start, nothing from fuel pump. This has happened before and new pump resolved it so off to Autozone. New fuel pump in and still no start. Very aggravating. I should learn and get a fuel pump not made in china...
The reason for the new pump was because yesterday went to start the car, crank but no start, nothing from fuel pump. This has happened before and new pump resolved it so off to Autozone. New fuel pump in and still no start. Very aggravating. I should learn and get a fuel pump not made in china...
Intermediate
Joined: Jan 2011
Posts: 44
Likes: 0
Sounds like you are not getting any power. Do you hear the noise when turning the key? Any power at the connector on top of the tank? Here a clicking noise at the relay? Hard to believe you would have multiple bad pumps, sound more like power issue to me.
This is what I would do
1 check power at the top of tank
2 Pull fuse (I think you did this)
3 check power when key turned on to fuse panel
4 check to see if you have power at orange wire at relay
This should tell you whether you have a power or pump issue.
This is what I would do
1 check power at the top of tank
2 Pull fuse (I think you did this)
3 check power when key turned on to fuse panel
4 check to see if you have power at orange wire at relay
This should tell you whether you have a power or pump issue.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Intermediate
Joined: Jan 2011
Posts: 44
Likes: 0
Are you saying you only have 6.2 volts at the top of the tank or at the orange wire going into the FP relay in the storage compartment?
If at the tank, check and make sure you are getting a go ground at the tank and where you are grounding for your voltmeter. Check the voltage at the fuse box when the key is first turned on with the fuse removed. One side will be next to nothing and the other should have 12v. If you are still seeing low voltage at the fuse, check the orange wire at the relay while it is connected to the relay, should be 12v. Also check the voltage on the tan-white wire t the relay, should be 12v. I can't remember but voltage may go away after the FP cycles for a couple of seconds so make sure to turn the key on and off each time you check.
If at the orange wire at relay, you are not getting 12v from the ECM for some reason.
Do you have a shop manual? If so, look on page 8a-86 and you can see all the wires I am talking about.
If at the tank, check and make sure you are getting a go ground at the tank and where you are grounding for your voltmeter. Check the voltage at the fuse box when the key is first turned on with the fuse removed. One side will be next to nothing and the other should have 12v. If you are still seeing low voltage at the fuse, check the orange wire at the relay while it is connected to the relay, should be 12v. Also check the voltage on the tan-white wire t the relay, should be 12v. I can't remember but voltage may go away after the FP cycles for a couple of seconds so make sure to turn the key on and off each time you check.
If at the orange wire at relay, you are not getting 12v from the ECM for some reason.
Do you have a shop manual? If so, look on page 8a-86 and you can see all the wires I am talking about.
Thread Starter
Intermediate
Joined: Aug 2013
Posts: 45
Likes: 0
6.2 volts at the top of the tank, but it could be because I'm turning on the key then going to the back and taking the voltage reading. I've checked it using various ground locations... all the same 6.2 volts.
As far as the other stuff, don't want to sound ungrateful for the advice, but I don't think I can do those things.
I've worked on getting to the fuel pump relay but honestly there is no way I'm getting that ecu out. I would never be able to get it screwed back in, just can't see and get to the screws well enough. Plus having to remove battery and ecu to get to the relay I don't see how to test voltage there.
And the fuse under the dash, again I can't see which fuse because the lettering has rubbed off many of them and if its the 10 amp one at the top, whew, I can't get the voltmeter on that if I can get the fuse out.
Do you know what this is in the photo below? Found it under the passenger-side storage compartment laying loose. There is a holder for it mounted on the forward wall. It makes a noise each time I reconnect the battery.
As far as the other stuff, don't want to sound ungrateful for the advice, but I don't think I can do those things.
I've worked on getting to the fuel pump relay but honestly there is no way I'm getting that ecu out. I would never be able to get it screwed back in, just can't see and get to the screws well enough. Plus having to remove battery and ecu to get to the relay I don't see how to test voltage there.
And the fuse under the dash, again I can't see which fuse because the lettering has rubbed off many of them and if its the 10 amp one at the top, whew, I can't get the voltmeter on that if I can get the fuse out.
Do you know what this is in the photo below? Found it under the passenger-side storage compartment laying loose. There is a holder for it mounted on the forward wall. It makes a noise each time I reconnect the battery.
Thread Starter
Intermediate
Joined: Aug 2013
Posts: 45
Likes: 0
I'm going back to my presumption of a bad fuel pump, here's why.
When I put 12 volts to the ALCL connector pin G for direct connection to the fuel pump I get nothing from the pump (it should run continuously). Also, with 12 volts still on pin G and the pump disconnected I get 12 volts on the voltmeter at the connector at the top of the tank (measuring on the brown wire which is the direct connection to the ALCL).
Therefore, I have voltage confirmed to the pump but pump still not working.
When I put 12 volts to the ALCL connector pin G for direct connection to the fuel pump I get nothing from the pump (it should run continuously). Also, with 12 volts still on pin G and the pump disconnected I get 12 volts on the voltmeter at the connector at the top of the tank (measuring on the brown wire which is the direct connection to the ALCL).
Therefore, I have voltage confirmed to the pump but pump still not working.
Melting Slicks
Joined: Jun 2011
Posts: 2,096
Likes: 15
6.2 volts at the top of the tank, but it could be because I'm turning on the key then going to the back and taking the voltage reading. I've checked it using various ground locations... all the same 6.2 volts.
As far as the other stuff, don't want to sound ungrateful for the advice, but I don't think I can do those things.
I've worked on getting to the fuel pump relay but honestly there is no way I'm getting that ecu out. I would never be able to get it screwed back in, just can't see and get to the screws well enough. Plus having to remove battery and ecu to get to the relay I don't see how to test voltage there.
And the fuse under the dash, again I can't see which fuse because the lettering has rubbed off many of them and if its the 10 amp one at the top, whew, I can't get the voltmeter on that if I can get the fuse out.
Do you know what this is in the photo below? Found it under the passenger-side storage compartment laying loose. There is a holder for it mounted on the forward wall. It makes a noise each time I reconnect the battery.
As far as the other stuff, don't want to sound ungrateful for the advice, but I don't think I can do those things.
I've worked on getting to the fuel pump relay but honestly there is no way I'm getting that ecu out. I would never be able to get it screwed back in, just can't see and get to the screws well enough. Plus having to remove battery and ecu to get to the relay I don't see how to test voltage there.
And the fuse under the dash, again I can't see which fuse because the lettering has rubbed off many of them and if its the 10 amp one at the top, whew, I can't get the voltmeter on that if I can get the fuse out.
Do you know what this is in the photo below? Found it under the passenger-side storage compartment laying loose. There is a holder for it mounted on the forward wall. It makes a noise each time I reconnect the battery.
Thread Starter
Intermediate
Joined: Aug 2013
Posts: 45
Likes: 0
Update:
Success!
Upon pulling the fuel sender I found a spaded connector had come loose during the installation yesterday. Reconnected, reinstalled, and she fired right up!
Thanks to Shawnee and SSROADSTER for your assistance!
Success!
Upon pulling the fuel sender I found a spaded connector had come loose during the installation yesterday. Reconnected, reinstalled, and she fired right up!
Thanks to Shawnee and SSROADSTER for your assistance!
Melting Slicks
Joined: Mar 2006
Posts: 2,248
Likes: 67
From: Warrington PA
Finalist 2020 C4 of the Year - Unmodified
