Car Wash Knockeded Out the Car
05-04-2011, 03:17 AM
#76
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I checked clarks for instructions on changing a fuel pump and it shows the fp under the car. My mechanic took out the trunk carpet and there was a round lid on the passenger side. Is that the fuel pump? He took the connection of there to see if it was getting power. I'm just a little confused ? Maybe some tears had access from the trunk?
05-04-2011, 10:33 AM
#77
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If the mechanic says it needs a fuel pump, put a fuel pump on it.
12V applied directly to the pump pretty much nails it down...
This is probably something you should pay him to do.
12V applied directly to the pump pretty much nails it down...
This is probably something you should pay him to do.
05-04-2011, 10:51 AM
#78
I will be paying him to do it. My only concern is that he thought the fuelpump was the fuel level sender unit in the trunk. So I am not sure if the fp is actually dead or not or if it is the real problem. Based on wat you all have read does it sound like the fp is the reason for no start, and replacing it will rectify the issue?
Overview:
•engine cranks but won't start
•getting spark
•no fuel pressure
•swapped dme relay, and fuel pump or car will not start
•jumped dme relay, plug and fuel pump or car will not start
•tach bounces a few mm when cranking
Note: I was told but not 100% sure nor confirmed but apparently the fuel pump was "upgraded" a few years ago. Do non oem or upgraded fp die faster?
Overview:
•engine cranks but won't start
•getting spark
•no fuel pressure
•swapped dme relay, and fuel pump or car will not start
•jumped dme relay, plug and fuel pump or car will not start
•tach bounces a few mm when cranking
Note: I was told but not 100% sure nor confirmed but apparently the fuel pump was "upgraded" a few years ago. Do non oem or upgraded fp die faster?
05-04-2011, 11:06 AM
#79
Three Wheelin'
I was going through the (numerous maintenance records on ) on my well maintained 89 T and that thing seemed to eat fuel pumps like they were candy!
On a lot of the FWD cars the fuel pump is inside the car and the sending unit and fuel pump or one unit so it would be a reasonable assumption. I believe it's in the back to the right covered by a plastic shield?
If it were me I would pull the pump and apply 12 volts to it and see if it works. But I can see a lot of reasons why that could be a bad idea! I'm thinking fire department, emergency clinic, blab,blab,blab...
but hey that's the way I roll!
On a lot of the FWD cars the fuel pump is inside the car and the sending unit and fuel pump or one unit so it would be a reasonable assumption. I believe it's in the back to the right covered by a plastic shield?
If it were me I would pull the pump and apply 12 volts to it and see if it works. But I can see a lot of reasons why that could be a bad idea! I'm thinking fire department, emergency clinic, blab,blab,blab...
but hey that's the way I roll!
05-04-2011, 11:31 AM
#80
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IF he applied 12V to the pump and it didn't work, its bad.
IF he applied 12V anywhere else, it didn't test the pump.
Seriously, its that simple. The car wash leads in many directions, and none of them point to a fuel pump failure simultaneously with a DME bath, but I guess it could happen.
Make sure he simply applies 12V directly to the pump before tearing into it any deeper than removing the cover.
For now, forget about relays, tachs, spark, and anything else. One thing at a time. Put 12V on the pump.
IF he applied 12V anywhere else, it didn't test the pump.
Seriously, its that simple. The car wash leads in many directions, and none of them point to a fuel pump failure simultaneously with a DME bath, but I guess it could happen.
Make sure he simply applies 12V directly to the pump before tearing into it any deeper than removing the cover.
For now, forget about relays, tachs, spark, and anything else. One thing at a time. Put 12V on the pump.
05-04-2011, 11:48 AM
#81
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Well, according to the poster his mechanic never tested the fp under the car. The question remains, is the mechanic a Porsche tech?
IF he applied 12V to the pump and it didn't work, its bad.
IF he applied 12V anywhere else, it didn't test the pump.
Seriously, its that simple. The car wash leads in many directions, and none of them point to a fuel pump failure simultaneously with a DME bath, but I guess it could happen.
Make sure he simply applies 12V directly to the pump before tearing into it any deeper than removing the cover.
For now, forget about relays, tachs, spark, and anything else. One thing at a time. Put 12V on the pump.
IF he applied 12V anywhere else, it didn't test the pump.
Seriously, its that simple. The car wash leads in many directions, and none of them point to a fuel pump failure simultaneously with a DME bath, but I guess it could happen.
Make sure he simply applies 12V directly to the pump before tearing into it any deeper than removing the cover.
For now, forget about relays, tachs, spark, and anything else. One thing at a time. Put 12V on the pump.
05-04-2011, 12:40 PM
#83
Three Wheelin'
It sounds like someone who works on cars in general to me? If a Porsche Tech looked for the fuel pump in the trunk, I'd be concerned but for the average wrench, it would be a logical assumption.
05-04-2011, 01:47 PM
#84
You guys are correct. He is not a Porsche tech he is just a general mechanic. I will ask him to come over again and try to see if the fuel pump turns on with a 12v shock. (You are correct he gave a 12v shock to the fuel level sender).
Since most things are for now pointing to the fuel pump, do you guys recommend a specific brand over another, maybe an after market one? I am on a budget, so I was thinking of getting a used one like the link Lart sent. Any feedback on that?
Since most things are for now pointing to the fuel pump, do you guys recommend a specific brand over another, maybe an after market one? I am on a budget, so I was thinking of getting a used one like the link Lart sent. Any feedback on that?
05-04-2011, 02:08 PM
#85
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You guys are correct. He is not a Porsche tech he is just a general mechanic. I will ask him to come over again and try to see if the fuel pump turns on with a 12v shock. (You are correct he gave a 12v shock to the fuel level sender).
Since most things are for now pointing to the fuel pump, do you guys recommend a specific brand over another, maybe an after market one? I am on a budget, so I was thinking of getting a used one like the link Lart sent. Any feedback on that?
Since most things are for now pointing to the fuel pump, do you guys recommend a specific brand over another, maybe an after market one? I am on a budget, so I was thinking of getting a used one like the link Lart sent. Any feedback on that?
05-04-2011, 03:20 PM
#86
When we gave the fuel level sender unit 12v should it have "turned on" and made any sounds? I just want to make sure that is not dead. Hopefully it is silent, or only engages when the fuel pump is on.
I also took a look at an old post and someone was having similar problems as me and they were told to try disconnecting the O2 Sensor then try to jump the DME relay from terminal 30 and 87b. For that person this worked and the reason was the O2 sensor wire was shorting due to heat melting the casing. The only thing is this person would blow the fuse in slot 34 which is for the fuel pump. Mine is not blown.
Lart, are you and the ebay seller the same person? You both have Lart in your names?
I also took a look at an old post and someone was having similar problems as me and they were told to try disconnecting the O2 Sensor then try to jump the DME relay from terminal 30 and 87b. For that person this worked and the reason was the O2 sensor wire was shorting due to heat melting the casing. The only thing is this person would blow the fuse in slot 34 which is for the fuel pump. Mine is not blown.
Lart, are you and the ebay seller the same person? You both have Lart in your names?
05-04-2011, 04:30 PM
#88
Race Car
OK if you have narrowed to down to fuel, first check the fuse for the O2 sensor and fuel pump. Then use the jumper wire for the dme relay to see if it comes on. If not check voltage at the pump with the jumper in. That will let you know if you have a short between the fuse box or if the pump is bad.
For the future I recommend having a fuel pressure gauge nearby to test for pressure whil cranking.
My usual course of action with these cars is
Tach bounce..yes skip r/f sensors and dme related at first. No the n check DME relay s/r sensors then DME connections/alarm
check for spark using a screwdriver inserted in one plug wire laying on the intake and watch for spark.
If spark then it is fuel and compression
Checking for fuel is easy with a pressure gauge, compression teh same with a gauge.
If there is fuel presure and compression is correct then you are pretty limited to injectors.
For the future I recommend having a fuel pressure gauge nearby to test for pressure whil cranking.
My usual course of action with these cars is
Tach bounce..yes skip r/f sensors and dme related at first. No the n check DME relay s/r sensors then DME connections/alarm
check for spark using a screwdriver inserted in one plug wire laying on the intake and watch for spark.
If spark then it is fuel and compression
Checking for fuel is easy with a pressure gauge, compression teh same with a gauge.
If there is fuel presure and compression is correct then you are pretty limited to injectors.
05-04-2011, 04:49 PM
#89
Thanks for the help Sid!!
The fuse for the O2 sensor is good (will double check once I am home). Tried the jumper cable to DME relay and fuel pump did not engage, even tried a DME relay from my friends working 951 and Fuel Pump did not engage. My mechanic checked for fuel pressure the old school way by opening the fuel line and having someone crank the car, the fuel did not come out with any more pressure then it was already coming out from unscrewing the fuel line, so he concluded no fuel pressure.
Next steps will be to check to see if the Fuel Pump is getting power (How much power should it be getting?). I will even try to give it power with a portable battery charger to see if it turns on.
I want to double check because I have read differing opinions on how to jump the DME, what terminals do you insert the wires to? I did it using 87, 87b and 30. Weird part was every time I removed the cables from 87b or 30 the turbo pump turned on, not if i removed the wire from 87. Even now when I crank the car with the DME relay in the turbo pump turns on as if it thought the car was running and then turned off (Maybe this is normal behavior for the turbo pump/DME Relay)?
The fuse for the O2 sensor is good (will double check once I am home). Tried the jumper cable to DME relay and fuel pump did not engage, even tried a DME relay from my friends working 951 and Fuel Pump did not engage. My mechanic checked for fuel pressure the old school way by opening the fuel line and having someone crank the car, the fuel did not come out with any more pressure then it was already coming out from unscrewing the fuel line, so he concluded no fuel pressure.
Next steps will be to check to see if the Fuel Pump is getting power (How much power should it be getting?). I will even try to give it power with a portable battery charger to see if it turns on.
I want to double check because I have read differing opinions on how to jump the DME, what terminals do you insert the wires to? I did it using 87, 87b and 30. Weird part was every time I removed the cables from 87b or 30 the turbo pump turned on, not if i removed the wire from 87. Even now when I crank the car with the DME relay in the turbo pump turns on as if it thought the car was running and then turned off (Maybe this is normal behavior for the turbo pump/DME Relay)?
05-11-2011, 03:28 AM
#90
UPDATE:
I replaced the fuel pump with the stock Bosch pump, and the fuel filter. Filled up some gas in the tank, charged the battery and turned the key a few times before trying to crank. The car did crank a few times the tach bounced up and down but I didnt hear the fuel pump turn on. I then tried to jump the DME relay and the fuel pump turned on! (it wouldnt turn on prior to being replaced even if DME was jumped).... But the car will still not turn on.
I have ordered a new DME relay.
Any other ideas? I know EHALL you said its my alternator.... is there anyway to do an alternator check before I purchase one, so that I am certain it was the problem?
Also a note, when I bench tested the old Fuel Pump it did not work.
I replaced the fuel pump with the stock Bosch pump, and the fuel filter. Filled up some gas in the tank, charged the battery and turned the key a few times before trying to crank. The car did crank a few times the tach bounced up and down but I didnt hear the fuel pump turn on. I then tried to jump the DME relay and the fuel pump turned on! (it wouldnt turn on prior to being replaced even if DME was jumped).... But the car will still not turn on.
I have ordered a new DME relay.
Any other ideas? I know EHALL you said its my alternator.... is there anyway to do an alternator check before I purchase one, so that I am certain it was the problem?
Also a note, when I bench tested the old Fuel Pump it did not work.