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Ok, so things aren't quite right yet. Using a better ground has stopped the headlights from changing the reading and it will now show the correct reading for a while, but after a short time it stops working and pressure drops to 10-20psi. I'm confident that the wiring is sorted now, so the problem is with the sender. I'm thinking it could be:

1. Faulty sender

2. An air bubble altering the reading

3. Thread tape blocking the opening

4. Fuel flowing straight past the opening and bypassing the sender

Anyone had a similar problem?

have you considered the gauge setup is ok? your fuel pressure could be low.

my fuel pressure gauge is currently fine but I do need to rewire my oil pressure and temp - they are both misbehaving. most car gauges are very sensitive and only run 1v max. as a result they are very suseptible to interfearance

yet to find any guage that is tested for accuracy

just checked autometer website adn Defi - no listing of the range of accuracy available.

I was talking more about independent testing, such as the Auto Speed ones (albeit dated now, they are a good comparison between OEM companies like VDO compared to flashy looking companies that aren't concerned with accuracy)

Link 1: http://autospeed.com/cms/A_1008/article.html

Link 2: http://www.autospeed.com/A_3032/hDg34uLtp_1/cms/article.html

have you considered the gauge setup is ok? your fuel pressure could be low.

my fuel pressure gauge is currently fine but I do need to rewire my oil pressure and temp - they are both misbehaving. most car gauges are very sensitive and only run 1v max. as a result they are very suseptible to interfearance

Yeah I did consider that but given that the car is running fine I'm fairly sure pressure is higher than the 0-10psi the gauge is showing! Either the sender or gauge is playing up, I just need to find time to work out which it is.

Ok, so things aren't quite right yet. Using a better ground has stopped the headlights from changing the reading and it will now show the correct reading for a while, but after a short time it stops working and pressure drops to 10-20psi. I'm confident that the wiring is sorted now, so the problem is with the sender. I'm thinking it could be:

1. Faulty sender

2. An air bubble altering the reading

3. Thread tape blocking the opening

4. Fuel flowing straight past the opening and bypassing the sender

Anyone had a similar problem?

the pressure would be around 40psi on a stocker, and woudlnt really vary that much when you give it a hit. + if your pressure was low your car would probably not be running rite.

its either the fualty sender, or possibly the thread tape, but in that case it wouldnt work at all.

wouldnt be an air bubble coz it would just clear itself within a split second, and definatly not no.4

its probably just the sender.

I was talking more about independent testing, such as the Auto Speed ones (albeit dated now, they are a good comparison between OEM companies like VDO compared to flashy looking companies that aren't concerned with accuracy)

Link 1: http://autospeed.com/cms/A_1008/article.html

Link 2: http://www.autospeed.com/A_3032/hDg34uLtp_1/cms/article.html

just so you know, I have an autometer boost gauge and a profec b and both gauges read identical (dont think the profec b is gonna be wrong!) just to give you an idea of accuracy, is I know its only boost and the electronic fuel and oil may be a bit more complex..

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