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The pressure regulator is on the high pressure pump I think. I think it's just a sensor on the rail.

I assume it should open and close to keep the fuel pressure within specified limits.

Do you have problems with the fuel pressure being incorrect?
 

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Discussion Starter #4 (Edited)
I thought it should be doing somthing that's why i asked, trouble is i have all the numbers on multiecuscan but i dont know if the numbers correct .....
The car is really hard to start whether it be hot or cold but more of a sod when its cold, they're are no warning on the dash but as a process of elimination ive Changed the glow plugs and relay, ive changed the crank sensor, cleaned the map, egr and the end of the manifold where its double skinned which was blocked in soot and done a forced regen but its still the same.
Ive noticed that if you put the key in and out a few times it sometimes starts a little quicker when cold which lead me to think fuel, i can hear the pump under the seat so i know thats ok but then i read a post on the 147 section where Fruity said the fuel pressure should be 360 ( or something like that) so with that in hand i went to the car to check mine and its 336 so its not bad ( is it ? ) , then i started highlighting a few other things on Multiecuscan and noticed the Pressure regulator not working so that's really why im here to ask if it should be opening and could it be a possible cause of the hard starting .... If its knackered im sure ive a spare in the garage which i could swap it with.

Edit: Untill i found this pressure reg not opening my next thought was a compresson test and was going to buy a kit but i read this post where he had to modify it as i didnt work and i dont want to be messing with things , so, Does anone have a link to a tried and tested kit and adapter they know works ? Or anyone in Telford Shrewsbury Stoke who fancies doing a test on mine, i'll pay obviously ...
https://www.alfaowner.com/Forum/alfa-159-brera-andamp-946-spider/1116946-compression-test-questions.html
 

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Check the leak back on the injectors....both times I've worked on my diesel cars with poor starting from cold (my Jeep and wifes old Golf) is turned out to be excess leak back on one injector which in turn made it difficult for the pump to reach the minimum pressure it required. If that pressure is not reached it will not fire the injectors. The Jeep was really bad in very cold weather until one day it would not start at all. One recon injector and it was back to instant firing. Worth a look.
 

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Discussion Starter #7
Swirl flaps?

I am due to remove them but in this case of hard starting i dont think it is ...

If i try and start the car in the morning cold i can put the key in crank the engine for a good 10 seconds and it wont start, yet if i pull the key out then back in it will start usually within 4 or 5 revolutions of the engine.
If in the morning from cold i put the key in then out and let it prime for a few seconds each time if will start again with in 4,5,6 revolutions of the engine that's why I'm thinking fuel ...
But its not just when its cold, its the same when the engine is hot but admittedly it is a little easier to start when warm/hot

... Though I'm probably wrong
 

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Discussion Starter #8
Check the leak back on the injectors....both times I've worked on my diesel cars with poor starting from cold (my Jeep and wifes old Golf) is turned out to be excess leak back on one injector which in turn made it difficult for the pump to reach the minimum pressure it required. If that pressure is not reached it will not fire the injectors. The Jeep was really bad in very cold weather until one day it would not start at all. One recon injector and it was back to instant firing. Worth a look.
I did check the injectors and number 3 is quite high at 3 and sometimes 4 mmls so in turn number 2 and 4 are -2.
I'll swop number 3 then but does that full pressure reg need to be opening ?
 

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Yep sensor one end, regulator the other. You will have one somewhere...maybe on the side of the rail (on my 2.0 its like the pic you posted). AFAIK all common rail diesels have them. On the negative side....ive never known a fuel rail pressure regulator to fail on any car ever!....Although I have seen quite a few wrongly replaced! Don't think the car would run as all if it failed....its only job is to release excess rail pressure.
 

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Discussion Starter #12
Interesting ..

But why isnt it showing up on Mutiecuscan as opening ?

To be honest the car goes and stops so its not major headache but i originally thought it might have something to do with the hard start which i now know it doesnt, i just intrigued to know why its not showing on Multiecuscan and where its located.
The only other thing with an electrical connection is a small sensor/regulator (?) on the side of the pump
 

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It will only open if the pressure gets to high....
 

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DRV is on the pump. Unlikely to be the problem, it basically stops the pressure from the pump when it gets a signal from the sensor in the rail that pressure is sufficient. Its a valve, not a sensor. Your rail pressure is within limits so the valve is doing nothing, as its designed to do. If you were to run the diagnostics on a run out the road you should see it working. But could you have a look at the cranking rpm from the diagnostics ? Just tick the rpm option on multiscan and turnover when cold. Also get the fuel pressure readings while cranking. Usually your issue is to do with slow cranking speed, caused by battery failing or starter. It needs a speed somewhere around 350rpm as a minimum to create enough compression heat and injector pressure. You can also check battery volts while cranking, which will be a good indicator for battery health. Check out below thread.

https://www.alfaowner.com/Forum/alfa-159-brera-andamp-946-spider/1171537-alfa-159-sw-1-9-jtd-starting-issues.html
 

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Discussion Starter #16
I replaced the battery for a good used 1 i had which made no difference so ive always thought it must be a lazy starter so today ive swapped the starter motor and it's made no difference at all. Which is nice.
Ive read the post via the link and i do have a small amount of white / grey smoke on start up which Ive put down to number 3 injector being pretty high at 4mmls but its booked in next Tuesday for a compression test before i start spending on injectors or even a different battery.
Ive uploaded 2 vid which shows the engine rpm and 2nd vid fuel pressure, you'll notice the long cranking but in the 2nd vid i pull the key out then back in and the car starts ... P.s. Please excuse the swearing its been a rather disappointing day.

Also while I'm here , ive attached a pic of part of the breather system on the back of the engine dribbling oil, the pic is taken from the back of the engine looking upwards so is that oil just a knackered joint or is there a build up which i should be concerned about ? The picture should be rotated 90 degrees to the right but it wont upload that way ...

Engine Speed ...

Fuel Pressure ....
 

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Your car is displaying the symptoms of either swirl flap failure causing low compression on one or more cylinders or an injector that is on its way out. The readings on no3 injector could be injector related or a problem winning the cylinder.
If I were you I would be checking the inlet manifold out,them flaps are a ticking time bomb
 

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Discussion Starter #18
As i say its booked in for a compression test so depending on the results i'll have the flaps out , if not its a scrapper.

Thank you everyone, Brillant as always.
 

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I'm going to stick my neck on the line and still say its battery. Because at 30 seconds on the video the engine catches, as the battery gives you 10.146v of power, which is the only time it gives you a figure higher than 9 point something, and the revs hit over 400rpm, again, for the only time they go above 300. Coincidence ? I'm not sure. To be certain, you could repeat the test, but with jump leads connected to another car, which has its engine running. You don't have to run the diagnostics, you'll know yourself if she starts immediately, which she should. Anything below 10 volts is just not enough to spin her to sufficient speed in my book.

Correction, just had another look, it does give above 10 volts earlier, but it does not go higher than 350 rpm. I'm convinced its battery, its just not spinning fast enough. And the guy in the post I referenced you to also found taking the key out and reinserting it helped it to start. You must rule out the battery before anything else. You can hear it is struggling to spin, and the volts shown should be showing more than 11, even before you crank it. That should be between 12 and 14 volts.
 

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Discussion Starter #20
My mate came around earlier so i attached jump leads to his battery with his car not running and it did indeed start straight away ....
 
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