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Discussion Starter · #1 ·
Hi All,

This is my first post asking a question, I hope I am posting in the right place

Short Story: Car Starts up for a few seconds..when I spray starting fluid into the throttle body inlet. When I put my finger on the Fuel pump relay it clicks when I turn on the ignition to acc position. all the lights in the dash comes on. Also normally I used to hear a ticking noise from the back of the car either when i started or a few minutes later and always thought of it as fuel pump priming, it is not doing it now. I also checked all the fuses in the side panel and they all have power. From reading up a on this forum, I don't know if I have a faulty fuel pump or faulty temperature sensor or something else. I will appreciate all help and input.

Long story:
I have not been driving the Passat regularly for the last six months. However I used to take it for a drive for at least 3-4 miles once every other week. The car was driving fine without any issues. Then last week when I went to start the cr the battery was completely dead. I had the battery recharged and tested and was told it is a good battery. I then installed the battery. As soon as I installed the battery and turned on the ignition key it was making a buzzing noise it was traced to the 204 relay. I turned off the car and after an hour tried to turn it on and same issue. Then I tried to crank the car and it tuned over fine and started but the buzzing continued and the car was running erratically and died out. I then replaced the ignition switch. After replacing the ignition switch , 204 was made a ticking noise slightly different (I think) and under the hood the middle liver around the throttle body pully was flickering. I then disconnected the battery and cleaned the throttle body after disassembling it from the engine (only the non electrical inlet and out and the cirular valve of all the gunk.) then i reinstalled it and tried to start the car. Based on what I read, it looked like the throttle body tried to do an auto alignment when the key was in the on position. However when i cranked it it once this stopped, the car didnt start. The first two times I tried to start it did the cycling ( i mean the throttle body) and then it stopped then when I try to crank the car it turns over but does not start. Now when I turn the key on to the acc position all the lights come on and when i listen by the throttle body there is a brief humming not correcting like before, and it stops and when i try to turn over the motor it does turn over but does not start. I had a spare fuel pump relay (372) I wapped this als, still not starting. In the Acc position it clicks motor turns over but does not start( except with starting fluid)

Further to this, I replaced all plugs and cleaned the MAf sensor, after this the car is turning over but not starting. When the key is in the acc position there is a brief humm from the throttle body only heard when i have open the hood and listen to it, in other words it is not audible from inside the car.

By the way, when the car was erratically running briefly after replacing the ignition switch, after the car cut out. I turned off the ignition and connected a scanner to read obdII codes (Autel Maxicheck). I then turned it on and did a scan and it came back saying 7 fault codes and it froze. Then i turned off the key and disconnected the scanner after this I reconnected the scanner and it has been giving me a "Linking error" I also tried another scanner and same issue.. not able to communicate. (somewhere on this forum I read it could be due to a fuse located in the box under the hood) I haven't had a chance to look at it yet ( It got dark outside).

To summarize right now if I spray a little starting fluid through the intake by the throttle body , the car stars for a couple of seconds and dies off. I tried this about 3 times and same result, so I feel it maybe fuel related or something I am ignorant about.

I would really appreciate all input to resolve this issue.

Thank you.:confused:
 

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It looks like you are not getting any fuel. Do not replace any parts until you have diagnosed where the fault is.
With the ignition on and fuse 28 connected, what is the voltage at both sides of fuse #28 ?
With the engine cranking and fuse 28 connected, what is the voltage at both sides of fuse #28 ?
 

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Discussion Starter · #3 ·
Hi Tom,
I appreciate the response.

Battery voltage : 12.5 V

With the fuse in , Key off, key on and cranking all shows close to 0 volts;
However with the fuse removed and testing across the prongs gives me 0.6V (Key on) and 0.49v-0.52v when cranking. ( I am hoping this is what you meant)
Thanks
 

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It looks like you are not getting any fuel. Do not replace any parts until you have diagnosed where the fault is.
Wise advice from Tom. It's common for people to throw parts at a malfunctioning car, but a dirty throttle, MAF, or plugs are not keeping your car from running, lack of fuel is. Being an early B5, the pump is old, so begin with the source of fuel (gas tank and fuel pump - and make sure there is gas in the tank! I was hugely embarrassed to waste all day on our car when my wife ran out of gas just as she got home).
 

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Discussion Starter · #5 ·
YLwagon,
Do you think the voltage at the fuse is normal. I was thinking it should be closer to 12V, I maybe wrong. Can anyone tell me if this looks like a power to fuel pump or fuel pump issue ?
What is the best course of action here. Since I dont know much about these cars, if someone can tell me or point me to the best sequence to follow from here, it will be really helpful.
Thanks again.
 

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Here's what I would do: find the black metal cover under the trunk mat with three screws, and remove it. Underneath will be the access to the fuel tank with two rubber hoses and an electrical connector. Disconnect that- it will require a small flat screwdriver inserted in a slot to rock back the latch inside, which will allow the connector to be pulled off. Next, arrange jumper wires to the two outside receptacles of that connector, which will correspond to the larger of the wires going to that connector. Attach those jumper wires to the terminals of a headlight bulb, which will simulate the load of the fuel pump. Now crank the engine, while watching the bulb. If it lights, then there is power to the pump connector. And if so, use an Ohmmeter to check the resistance of those outer pins on the tank access cover. It should be a few Ohms, but if higher, or infinite, then the pump's motor is bad.
 

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year?sorta an idea (2000)miles? and do you have any previous service records? and are you in a damp location?,car garaged? and you are definitely in the right spot for experienced answers!
 

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Discussion Starter · #9 ·
Good question. It is a 1999 Passat. It is in an open air parking spot in the apartment. a few months ago during heavy rains water got in the passenger side under the mat. Traced it back to the drain hole under the battery being clogged. There is a tree near the car parking spot and during fall flowers and fine leaf end up on the trunk and makes its way to the drain plug and block it. In fact, it shorted out the passenger side airbag sensor and had to replace it. Since then I have moved the car to another spot. I had let the water dry off from the carpet before using the car.
 

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If its sat for a while my money is on fuel system issues. My bread and butter plus the plate it's eaten off of is all paid for because of our countries cheap low quality and high profit margin gasoline.

Fuel has an average shelf life of 30 days. After that it starts to varnish and become corrosive. Ethanol containing fuels also attracts moisture (humidity in the air) and you'll often find small amounts of water contamination.

So if you're getting power to the fuel pump id next check for pressure. Then id check fuel sock, fuel filter and last but not least injectors. If you are not 100% sure the gas wont all be used up in 30 days put a stabilizer in your fuel. Or dont....some shop will thank you for it. Same goes for lawn equipment, boats, rvs, jetskis, generators, motorcycles, atvs etc...etc...
 

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Hi Tom, I appreciate the response.

Battery voltage : 12.5 V

With the fuse in , Key off, key on and cranking all shows close to 0 volts;
However with the fuse removed and testing across the prongs gives me 0.6V (Key on) and 0.49v-0.52v when cranking. ( I am hoping this is what you meant) Thanks
This is what I meant.

If you don't have more than 9V at fuse #28 while cranking, the fault is forward of the front seat.
It is not the fuel pump or anything near it.

I suggest you re-check the voltage at fuses.
With everything connected including fuses, and the ignition key in the run position:
What is the voltage between ground and each side of fuse #28 ?
What is the voltage between ground and each side of fuse #32 ?
What is the voltage between ground and each side of fuse #34 ?

With everything connected including fuses, and the engine cranking:
What is the voltage between ground and each side of fuse #28 ?
What is the voltage between ground and each side of fuse #29 ?
What is the voltage between ground and each side of fuse #34 ?

Some of the possible faults:
1. Fuel pump Relay (This is most likely)
2. Ignition switch
3. Wiring, or contacts in relay base
4. ESS (Crank position sensor)
5. ECM (This is very unlikely)

Here are a couple of relay tests that you could do.
Relay test 1:
With everything connected and engine cranking measure the voltage between ground and fuse #28, if the voltage is above 0.5V, and more than 1V below the voltage at fuse #32, it is about 95% sure the relay is faulty.

Relay test 2:
With everything connected and the engine cranking measure the voltages at the FP Relay. Connect the positive probe to term #30 and the negative probe to term #87a,
if the voltage is more than 0.5 volt, and more than 1V below the voltage at fuse #32 to ground, the relay or a connection in its socket is faulty.
 

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Discussion Starter · #13 ·
It looks like you are not getting any fuel. Do not replace any parts until you have diagnosed where the fault is.
With the ignition on and fuse 28 connected, what is the voltage at both sides of fuse #28 ?
With the engine cranking and fuse 28 connected, what is the voltage at both sides of fuse #28 ?
Tom I was also waiting to hear fromyou as you originally asked me to check the voltages before proceeding. What are your thoughts ?
 

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Discussion Starter · #14 ·
Tom I was also waiting to hear from you as you originally asked me to check the voltages before proceeding. What are your thoughts ?
Looks like we both posted at about the same time so please ignore the last comment... I will also look into each of the fuse voltages and let you know tommorow. It is 1.30 AM here !!
 

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Discussion Starter · #15 ·
If its sat for a while my money is on fuel system issues. My bread and butter plus the plate it's eaten off of is all paid for because of our countries cheap low quality and high profit margin gasoline.

Fuel has an average shelf life of 30 days. After that it starts to varnish and become corrosive. Ethanol containing fuels also attracts moisture (humidity in the air) and you'll often find small amounts of water contamination.

So if you're getting power to the fuel pump id next check for pressure. Then id check fuel sock, fuel filter and last but not least injectors. If you are not 100% sure the gas wont all be used up in 30 days put a stabilizer in your fuel. Or dont....some shop will thank you for it. Same goes for lawn equipment, boats, rvs, jetskis, generators, motorcycles, atvs etc...etc...
PickleRick,
I now also have a feeling it is likely fuel related issue... I will also keep in mind of adding a stabilizer thanks.
 

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Briggs and Stratton sells the best priced stabilizer ive found. Locally the msrp is about 15 bucks to treat up to 80 gallons for up to 2 years. It also helps with the issues found in our cheap, unstable ethanol containing fuel. I consider it a superior product over the stabil brand. If you have a local northern tool or tractor supply company you can find it there or local lawn mower mom and pop stores.
 

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Discussion Starter · #17 ·
Briggs and Stratton sells the best priced stabilizer ive found. Locally the msrp is about 15 bucks to treat up to 80 gallons for up to 2 years. It also helps with the issues found in our cheap, unstable ethanol containing fuel. I consider it a superior product over the stabil brand. If you have a local northern tool or tractor supply company you can find it there or local lawn mower mom and pop stores.
Thanks
 

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Discussion Starter · #18 ·
This is what I meant.

If you don't have more than 9V at fuse #28 while cranking, the fault is forward of the front seat.
It is not the fuel pump or anything near it.

I suggest you re-check the voltage at fuses.
With everything connected including fuses, and the ignition key in the run position:
What is the voltage between ground and each side of fuse #28 ?
What is the voltage between ground and each side of fuse #32 ?
What is the voltage between ground and each side of fuse #34 ?

With everything connected including fuses, and the engine cranking:
What is the voltage between ground and each side of fuse #28 ?
What is the voltage between ground and each side of fuse #29 ?
What is the voltage between ground and each side of fuse #34 ?

Some of the possible faults:
1. Fuel pump Relay (This is most likely)
2. Ignition switch
3. Wiring, or contacts in relay base
4. ESS (Crank position sensor)
5. ECM (This is very unlikely)

Here are a couple of relay tests that you could do.
Relay test 1:
With everything connected and engine cranking measure the voltage between ground and fuse #28, if the voltage is above 0.5V, and more than 1V below the voltage at fuse #32, it is about 95% sure the relay is faulty.

Relay test 2:
With everything connected and the engine cranking measure the voltages at the FP Relay. Connect the positive probe to term #30 and the negative probe to term #87a,
if the voltage is more than 0.5 volt, and more than 1V below the voltage at fuse #32 to ground, the relay or a connection in its socket is faulty.

Hi Tom & All,
I am a little confused... Here is why:
When I turn on the key and had my hand on top of the fuel pump relay i felt it was clicking. Then i noticed that the neighboring relay was also clicking. I then took off the cover of the fuel pump relay and noticed it was not clicking when i turn on the key. ( I had previously swapped out the ignition switch .. so I am guessing that is fine). I then removed the relay and tried a spare one I had in the slot also a 372 relay it also does not click in the key on position. I then cleaned off the contact point that had some black spots on it placed the original relay (with the open cover ) back in its slot. I proceeded to manually click it with key in on position and the relay did not run the pump when the points made contact. I also noticed the first prong made more of a contact than the second and third prong ( I am referring to the contact points inside the relay, I dont know if this is normal), I dont know if both my relays are bad.

Voltage measurements:
At the relay socket ( ie where you insert the relay onto the board, they were labelled from 16 upwards and each of the slot to the ground voltages were as follows:

#16 0.3v
#17 12.3v
#19 12.3v
#20 5.1v
all the others were reading zero volts (Is this Normal, do I have both bad relays ?)

At the fuse:
What is the voltage between ground and each side of fuse #28 ? = 0v
What is the voltage between ground and each side of fuse #32 ? =12.4v
What is the voltage between ground and each side of fuse #34 ? = 5.1v

I really appreciate all the help you are all providing. One big lesson learned so far, open the relay cover to make sure it is clicking!!, otherwise it could be a neighboring relay clicking in tandem !!.
 

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I don't remember whether the fuel pump relay has more than one set of contacts, but if so, and one set is larger, that would be for the pump motor. The relay contact identified as #30 should be at battery voltage. The opposite contact arm should be at zero Volts when it's contact is not touching the first one, being grounded through the pump's motor- that will be the 'load' contact. Now close the contacts together, and measure the previously zero Voltage contact arm; should now be battery voltage. If the pump doesn't run, set your DVM to Ohms and measure resistance to ground at the load contact arm. If you don't see a small resistance (several Ohms) then the pump motor is likely bad.
 

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Discussion Starter · #20 ·
YLwagon,
The contact I was talking about was inside the relay itself, ie once the cover is open ie the top piece that you can push on manually. It has 3 contact surfaces, in otherwords the metal plate that clicks to make contact that is spring loaded on the top of the electromagnet that makes contact when the relay is powered.
The other question is shouldn't the relay click when I turn the key on?... it is not doing that.
 
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