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I know this is an old thread, but maybe someone can help me.
I have an '01 C5 and only have 5 psi fuel pressure with the key on. It has a Racetronix fuel system with the harness that runs power direct to the pump. It was installed by the previous owner and I tried contacting Racetronix to get instructions or a wiring diagram and never heard back from them.
The car ran fine for a long time after I bought it. It just quit on me one day and now no fuel pressure.
Fuse and relay both tested good.
On the factory fuse block I measured voltages and I have no voltage on 87 where I should have constant 12V.
I do get 12V on 86 when I turn the key on.
Does anyone have info on how the Racetronix stuff is wired in?
Any ideas would be appreciated.
Have you joined our support forum where there are diagrams and diagnostic docs?
Well when I ttraced mine back to pump I was getting voltage. The pump was fried. I bought exact pump swapping was easy because all the wiring was the same. Kit was cheap also. Of course mine died with a full tank go figure. Good luck
I was able to find the direct power harness that goes from the alternator to the fuel pump. The 20A fuse there was melted. It apparently had gotten very hot before it blew, almost like when you have a big amp with a power wire that is too small, but it's 10 gauge wire.
I replaced it and ran the car for a while and the fuse didn't get hot and had good stable fuel pressure.
Where is that fuse as i'm having the same problem?
Where is that fuse as i'm having the same problem?
I responded in the other thread but I saw you posted here and then clicked on your profile...I also have an IC Maggie and had intermittent fuel problems but not as bad as you. If your install is like mine you have your coolant tank on top of your battery...look under there and there are 2 inline fuse holders for your magnavolt...open them up and pull out the fuse...one of mine literally came apart in my hand
I ended up going to Radio Shack for a 10ga inline fuse holder and splicing it it...no problems since if this is the case with you I recommend calling any auto parts place before you go as they don't all carry inline fuse holders with 10 ga wire...Radio Shack or stereo shop is your best bet.
If you are checking at the relay socket(i.e relay removed), you should have the following(as label in the pic):
Measurements taken key to on position:
30 = O volts
86 = 12 volts ( for two seconds)
87 = 12 volts ( constant)
Measurement taken key to off position:
85 = Ground (should be low resistance i.e. .3 ohm or below)
No offense, but I'm questioning how you are taking the measurements, since all these things failing at the same time are unlikely....unless the car has been in an accident.
When you jump 30 to 87(of the relay socket), you should have 12 volts at the fuel pump connector.....unless there is a wiring problem.
There should be a ground at 85.....unless the ground is corroded at SP122 (located under the battery tray), or G105 (left lower side of block) is damaged.
There should be 12 volts at 86 when the key is first turned on, unless the PCM is not providing it.
I did most of this yesterday, and can confirm with the test light procedure you showed in the video all grounds referenced are OK, PIN 30 & 85. In reality all these grounds were disassembled and cleaned which meant broken pins turned into screws with serrated washers to help maintain grounds.
So at this point it is looking like a fuel pump module, unless there is a specific test that can be done at the pump.
First off can you include the year of the car in your profile or in your initial thread...this helps us to help you !!...now is the car a cranking no start ??...if you jump pins 87 and 30 at the relay does the pump run ??...the more info you can pass on the better...if it doesn’t run now you have to access the pump at the bottom of the left fuel tank if you own an early 2003 and prior and check your power and grounds at the pump...my ‘01 fuel pump draws around 6 amps at 5350 RPM at idle !!...have you checked fuel pressure at the fuel rail ??
97 as in the start of this thread
i have done all the ground checks indicated and
i did the pin jumps shown in the video
the cars cranks
the car will try to run on ether if you shoot that in the inlet
no fuel pressure though when it initially died right after a fill up I did hear the pump prime once. After that the last few days, haven’t heard it run for that two seconds on key on
The fuel sender unit appears to have been “serviced” at some time in the past
the test you mentioned Is new, had not seen that one
I will need to try in next day or so
Ok, your best bet is to access the pump and remove the connector and then apply 12 volts to pin A ( gray wire) and a ground to pin D ( black wire) of the pump...if the pump does not operate its toast !!
Next question is the battery ground cable - where does that go - to upper left side of engine (?) and how to access that if in fact that is where it goes...
Don’t know if you jumpered pins 87 and 30 at the fuel pump relay ??...pump should run !!...if not see if you have power at the gray wire at the connector with 87 and 30 jumpered together...ground is G 401 at the frame rail Inboard of the left rear tire...remove the wire terminal at G401 and using an ohm meter see if you have continuity between the black wire at the connector and G401 !!
I had done that and any of the other diagnostics up front - as a part of reading this thread....
All the studs busted and were repaired and cleaned up, hopefully that will clean up some of the ghosts I had seen over the last month or so - but were not present at time the car quit.
Big update, something told me look at the relays.... it was a bad or wrong after-market relay.
I had done that and any of the other diagnostics up front - as a part of reading this thread....
All the studs busted and were repaired and cleaned up, hopefully that will clean up some of the ghosts I had seen over the last month or so - but were not present at time the car quit.
Big update, something told me look at the relays.... it was a bad or wrong after-market relay.
Thanks for all the help,
If you think the fuel pump relay is bad swap it with another !!...I use the horn relay !!
if this is the case with you I recommend calling any auto parts place before you go as they don't all carry inline fuse holders with 10 ga wire...Radio Shack or stereo shop is your best bet.
