Signum z22yh fuel pressure advice....

yayoboy

Hi all, my 03 signum elite has the common fuel pressure problem, I bought the car with this fault for next to nothing, checked the codes as the eml was on and as expected misfire and fuel pressure malfunction showed.

I have gone through the vauxhall field remedy apart from testing the low side with a manometer ( this will be done next couple of days as my unc is gonna lend me one from his work )
Results for the rest via opcom,

Regulator feedback at tick over : hovers around the requested 5000kpa. ( above 600kpa )

Fuel pressure sensor voltage at 3000 rpm with regulator disconnected : 0.6/.07v ( below 1.2v )

So according to that, all is well, BUT I have noticed that when I rev the car up to 4000 rpm ( the point the car starts to miss/struggle ) the actual regulator feedback is way different from the desired eg desired 10000kpa actual 2000kpa

So would this suggest the pump or the regulator in your opinions?

I have done a couple of these before, but they have both been obvious ( reg feedback less than 600kpa ) so the changed the pump and all ok, but Sod's law when I do one for myself it isn't as clear lol!

Thanks in advance for any feedback, regards sean

Matt

@[deleted] is pretty clued up on these.

yayoboy

Thanks for reply matt, hopefully rushy will drop by

evocarlos

https://z22se.co.uk/threads/vauxhall-fault-code-p1191-5a-help-needed.24446/

yayoboy

Thanks for the reply Carlos, I have checked that thread but his fuel pressure reg was reading less than 600kpa, where as mine reads the requested on idle, it only changes when you rev it hard, I'm 99% sure it is the pump but just looking for assurance that it is thanks

evocarlos

i dont have much hands on with the z22yh but can only go by the info in the field remedy it is the definitive way to check which part is at fault
and there is only 4 parts that can go wrong in that system main tank fuel pump,hp fuel pump,pressure sensor,pressure regulator
there is a manometer port for main fuel pump pressure checking on the incoming fuel line conveniently its the same fitting as a refrigeration gauge set

yayoboy

Yes that is the last thing I have to check I'm just awaiting a borrowed one. All my feedback via opcom for the field remedy appears to be in spec, see my first post, this is why I'm cautious to just spend £400 on pumps and regs without being 100% sure.

The reading under heavy throttle (4000rpm and over) is the only thing that doesn't match the desired kpa as stated before, but hoping someone can confirm that 'yes it's the pump' or 'yes it's the reg' who might have had similar readings. Thanks for reply 🙂

yayoboy

Update, took the pump off and stripped it down as I thought it was going to be the most likely culprit.... Seals surprisingly were ok but looks as if it's lost it's oil so I'm going to try the drill and tap mod and refill it, fingers crossed 🙂

Also to try and eliminate things that could be causing my issue, does any one know how you check the timing on this, ive got the cam cover off and the chain looks at the right tension, and the guides and tensioner look ok no signs of wear/missing bits, just would like to confirm the timing, thanks

yayoboy

Update...... 😃 😃 😃 it's worked, stripped the pump, knocked out the ball bearing, cleaned, reassembled and topped up with atf, put bearing back in and vrroooom lol back up to full power 😃 happy days, thanks for all advice, I'll be doing a how to on this as it'll save people £££ if their seals having gone!

Matt

yayoboy said:
Update...... 😃 😃 😃 it's worked, stripped the pump, knocked out the ball bearing, cleaned, reassembled and topped up with atf, put bearing back in and vrroooom lol back up to full power 😃 happy days, thanks for all advice, I'll be doing a how to on this as it'll save people £££ if their seals having gone!

Excellent! Don't forget to put the how to into the Resource section, and you can try the new version out 😉

yayoboy

Will do mate

yayoboy

Resource done 😉

Matt

yayoboy said:
Resource done 😉

Thank you very much 🙂