Fuel pressure regulator.
Discussion
Hi Chaps,
Anyonr had a faulty fuel pressure regulator before? Not sure I have one but there is an issue with something on the fuel side. The pump wont stop priming and the engine wont start, but will fire. If I listen to the regulator it makes a lot of noise (it may do this anyway). If the pump does stop priming (sometimes it does) it does start but will shortly splutter on and off and then stop. On turning on the ignition again sure enough the pump wont stop priming again. Also, and this may be a coincidence, but it I play with the fuel return pipe from the regulator I can make it stop and start priming. I can't do this with any confidence, that it is me in fact, making it happen, or it's just by chance, as sometimes it has an effect and sometimes it doesn't. Is there any way to test it for sure apart from removing it and fitting a fuel pressure gauge on it (which I dont have)?
Many thanks
Pete.
Anyonr had a faulty fuel pressure regulator before? Not sure I have one but there is an issue with something on the fuel side. The pump wont stop priming and the engine wont start, but will fire. If I listen to the regulator it makes a lot of noise (it may do this anyway). If the pump does stop priming (sometimes it does) it does start but will shortly splutter on and off and then stop. On turning on the ignition again sure enough the pump wont stop priming again. Also, and this may be a coincidence, but it I play with the fuel return pipe from the regulator I can make it stop and start priming. I can't do this with any confidence, that it is me in fact, making it happen, or it's just by chance, as sometimes it has an effect and sometimes it doesn't. Is there any way to test it for sure apart from removing it and fitting a fuel pressure gauge on it (which I dont have)?
Many thanks
Pete.
Hi Pete
Not had a fault with the regulator itself but I did have a problem a couple of years ago when the small vacuum pipe that runs from the throttle, just under the TPS along the nearside rocker box and into the Regulator, split. The cure was to cut the end off and secure it with a new clip. The symptoms were an OK tickover but the engine ran so badly I thought it was catastrophic
might be worth checking that tube before paying anything out for a new regulator.
fingers crossed for you...
K
Not had a fault with the regulator itself but I did have a problem a couple of years ago when the small vacuum pipe that runs from the throttle, just under the TPS along the nearside rocker box and into the Regulator, split. The cure was to cut the end off and secure it with a new clip. The symptoms were an OK tickover but the engine ran so badly I thought it was catastrophic
might be worth checking that tube before paying anything out for a new regulator.
fingers crossed for you...
K
Kevin,
Thanks but I think mine is slightly different. It doesn't even tick over ok but hunts really badly for a few seconds then stalls. I have checked all the pipes and can't see anything but I think removing the unit and looking might be a way forward as it is quite hard to see it all. I might just replace it anyway with the power boost vavlve so often quoted. Where does the vacuum hose go into the regulator anyway because last night I could only see two pipes into it and I thought they were both fuel pipes! It was making a noise like air rushing somewhere though but I put that down to the pressure of the fuel flowing through it.
Thanks
Pete
Thanks but I think mine is slightly different. It doesn't even tick over ok but hunts really badly for a few seconds then stalls. I have checked all the pipes and can't see anything but I think removing the unit and looking might be a way forward as it is quite hard to see it all. I might just replace it anyway with the power boost vavlve so often quoted. Where does the vacuum hose go into the regulator anyway because last night I could only see two pipes into it and I thought they were both fuel pipes! It was making a noise like air rushing somewhere though but I put that down to the pressure of the fuel flowing through it.
Thanks
Pete
I'm away from home at the minute so cant get to the car or my previous pic's but from memory the vacuum tube was on the rear of the regulator. if you trace it from the throttle along the nearside rocker box you should be able to feel where it goes in the regulator. I'm not sure if it would give off much of a sound if it were loose or missing but its definitely worth a check to eliminate it if nothing else.
K
K
Thanks Jay and Kevin,
Managed to get home during lunch and have a look and yes you are right it is tucked at the bottom and behind. Sadly all ok though. I did notice however it is just pushed on with no clip, is that right? I tried removing the return fuel pipe to blast some carb cleaner inside in case anything is stuck but there is some starnge connector that seems imposible to undo. It look slike it has a red rotating collar that is protecting the fitting but I cant see how to remove it, and boy have I tried. I then removed the unit from the fuel rail and blasted some card cleaner in there instead but to no avail. Still not convinced it is the pressure regulator anyway. How does the ECU no when the fuel is up to pressure and cut the pump? Is there a sensor somewhere that may be at fault?
Thanks again,
Pete
Managed to get home during lunch and have a look and yes you are right it is tucked at the bottom and behind. Sadly all ok though. I did notice however it is just pushed on with no clip, is that right? I tried removing the return fuel pipe to blast some carb cleaner inside in case anything is stuck but there is some starnge connector that seems imposible to undo. It look slike it has a red rotating collar that is protecting the fitting but I cant see how to remove it, and boy have I tried. I then removed the unit from the fuel rail and blasted some card cleaner in there instead but to no avail. Still not convinced it is the pressure regulator anyway. How does the ECU no when the fuel is up to pressure and cut the pump? Is there a sensor somewhere that may be at fault?
Thanks again,
Pete
Shame...
have you tried just disconnecting the TPS and see how it runs. I also saw in the search that someone swapped the AFM connections over top to bottom and saw an improvement ? I didnt think you could do that but thats what he said...
Have you disconnected the ECU for a minute to see if theres any kind of improvement/reset ? - sorry - that comes from my IT "switch it off and switch it back on again" book of cures
K
ETA this thread... see last post...
http://www.pistonheads.com/gassing/topic.asp?h=0&a... loss of power
have you tried just disconnecting the TPS and see how it runs. I also saw in the search that someone swapped the AFM connections over top to bottom and saw an improvement ? I didnt think you could do that but thats what he said...
Have you disconnected the ECU for a minute to see if theres any kind of improvement/reset ? - sorry - that comes from my IT "switch it off and switch it back on again" book of cures
K
ETA this thread... see last post...
http://www.pistonheads.com/gassing/topic.asp?h=0&a... loss of power
Edited by ketvrin on Wednesday 6th April 18:01
Pete
No worries - at least you've found it and eliminated it.
Just out of interest my fuel pump primes and then continues to 'whine' whilst the engine is running (permanently) & always has - never had a problem though.
Not sure whether it's supposed to but I work on the theory that 'if it ain't causing a problem don't try and fix it'.
I'd agree with Kev on the disconnecting the TPS and/or ECU and see what happens.
Sod's law dictates it will be something small that's hard to find!!
Cheers
Jaye
No worries - at least you've found it and eliminated it.
Just out of interest my fuel pump primes and then continues to 'whine' whilst the engine is running (permanently) & always has - never had a problem though.
Not sure whether it's supposed to but I work on the theory that 'if it ain't causing a problem don't try and fix it'.
I'd agree with Kev on the disconnecting the TPS and/or ECU and see what happens.
Sod's law dictates it will be something small that's hard to find!!
Cheers
Jaye
Thanks all for your replies.
Neil - I replaced the relay but sadly not that.
Kevin - Tried the mass airflow sensor swap and yes the engine still ran but doesn't help with the fuel pump or running issue. I have fitted a new TPS but not sure why that would cause the pump to run continuously.
Jaye - Mine has always primed (quite noisy) and then stopped. The car will start and run fine if it does this, but not otherwise. If it happens while the car is running the car stumbles a few times then stalls. It also smells badly of fuel at the same time.
I can only guess it is over fuelling but I can't work out why...
Pete
Neil - I replaced the relay but sadly not that.
Kevin - Tried the mass airflow sensor swap and yes the engine still ran but doesn't help with the fuel pump or running issue. I have fitted a new TPS but not sure why that would cause the pump to run continuously.
Jaye - Mine has always primed (quite noisy) and then stopped. The car will start and run fine if it does this, but not otherwise. If it happens while the car is running the car stumbles a few times then stalls. It also smells badly of fuel at the same time.
I can only guess it is over fuelling but I can't work out why...
Pete
Others will probably know better but here goes a couple of thoughts...
a) Fuel pump is on it's way out - new fuel pump required?
b) The fuel is not returning properly to the fuel tank, therefore causing over fuelling?
Well, that's by 'penny's worth' - I'm sure others will be along with suggestions in due course.
Cheers
Jaye
a) Fuel pump is on it's way out - new fuel pump required?
b) The fuel is not returning properly to the fuel tank, therefore causing over fuelling?
Well, that's by 'penny's worth' - I'm sure others will be along with suggestions in due course.
Cheers
Jaye
Road2Ruin said:
I might just replace it anyway with the power boost vavlve so often quoted.
You don't want one of those, unless your ECU has been mapped to suit one (and why would you do that?). All they do is make the engine run richer under load and/or leaner off load. And since the engine is already set up with the correct fuelling based on the standard regulator, this means it will be too rich under load and/or too lean off load.Kevin,
Not checked the pressure yet as I dont own a fuel pressure gauge. If it comes down to this the local garage will have to get invlolved, if I can get it there!
GreenV8S - Comment noted. I did think it was a bit of over selling on the part of the companies in question. The only problem is if the pressure regulator is faulty I cant find a new one to buy!
Will try disconecting and re-connecting ECU tonight and then check the multiplug by wiggling the wires in it, then I might kick it in the dashboard to see if that helps.
Pete
Not checked the pressure yet as I dont own a fuel pressure gauge. If it comes down to this the local garage will have to get invlolved, if I can get it there!
GreenV8S - Comment noted. I did think it was a bit of over selling on the part of the companies in question. The only problem is if the pressure regulator is faulty I cant find a new one to buy!
Will try disconecting and re-connecting ECU tonight and then check the multiplug by wiggling the wires in it, then I might kick it in the dashboard to see if that helps.
Pete
ketvrin said:
you still have the offer of the loan of the Star Tester...
dont kick her in the dash, do a Basil Fawlty and give her a damn good thrashing with a branch
K
Ha Ha Ha. Dont think I have any birch trees handy. Thanks for the offer of the Star tester, it may come to that. I will try and rule out all other posibilities first, it's just a shame to have it in the garage when we have such good weather!dont kick her in the dash, do a Basil Fawlty and give her a damn good thrashing with a branch
K
What extactly does the star tester do?
Pete
Hi Pete
Sorry to hear of your continued woes. It is so frustrating.
I'm afraid I can't give much advice, but you do have my sympathy.
Do try the star tester. I was stuck with a problem that was very hard to diagnose a couple of years ago that the tester solved in a matter of minutes. In future it will be one of the first tests I carry out
Just plug it in and it will test various systems for you. In my case it identified a loose connection that, to the eye, looked perfect.
Hope that you get sorted soon
Tim
Sorry to hear of your continued woes. It is so frustrating.
I'm afraid I can't give much advice, but you do have my sympathy.
Do try the star tester. I was stuck with a problem that was very hard to diagnose a couple of years ago that the tester solved in a matter of minutes. In future it will be one of the first tests I carry out
Just plug it in and it will test various systems for you. In my case it identified a loose connection that, to the eye, looked perfect.
Hope that you get sorted soon
Tim
Its a diagnostic tool. you plug it in and follow the instructions for tests with the ingition off, then ignition on, theres a wiggle/waggle test where you do that to all the connections and sensors and relays etc while keeping a beady eye on an LED which might blink if you find a dodgy connection, then theres the engine on tests including a blip of the throttle. Any faults found will show on the screen as a code which you then look up in a table to identify the culrpit.
Its quite a comprehensive test but only takes a few minutes to do.
K
Its quite a comprehensive test but only takes a few minutes to do.
K
ketvrin said:
Its a diagnostic tool. you plug it in and follow the instructions for tests with the ingition off, then ignition on, theres a wiggle/waggle test where you do that to all the connections and sensors and relays etc while keeping a beady eye on an LED which might blink if you find a dodgy connection, then theres the engine on tests including a blip of the throttle. Any faults found will show on the screen as a code which you then look up in a table to identify the culrpit.
Its quite a comprehensive test but only takes a few minutes to do.
K
I must admit that does sound good. If you dont mind posting that would be great, I think in this instance it could really help. I will PM you my address and make sure I refund the postage plus some beer (or wine or cider) money.Its quite a comprehensive test but only takes a few minutes to do.
K
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