[Mk2] [Turbo] fuel vacuum problem

[possel]

hi all hopeing someone can help me out here, iv recently rebuilt my mr2 and for some reason i have no vacuum coming from my fuel rail, i found this out when i was setting up the fuel pressure (40psi). i know it was there before i rebuilt it as that was when i installed the adjustable fpr. also say around 6-7k when flooring it when i go up the gears its really hesitant to get goin again for a second or 2????? PLEASE HELP ME

[3S Service Centre]

if using a aftermarket fpr, have you got a vacume line going to it from the inlet manifold?

[possel]

yeah all i done was replace the regulator so used the orignal vacuum line coming from the top of the fuel rail, just very strange that nothing is there now??

[3S Service Centre]

dude your confusing me.

There is no vacume from the rail ever, the vacume comes from the inlet manifold to the stock fpr via little metal pipes across the rail.

If you running a aftermarket fpr, you need to take a feed direct from the manifold to the fpr, don't take the feed from the little metal pipes above the rail if they are not plumbed to the manifold.

James

[possel]

on the very top of the fuel rail theres the really thin plate that has a tiny pipe coming from it, just behind injector 2? has 3 10mm bolts that screw into the lower part of the fuel rail that the injectors sit in, or am i just being completley stupid?

[possel]

soz make that behind injector no 3

[3S Service Centre]

Yes that thin little pipe comes from the manifold, passes under the throttle body and goes to the standard fpr.
It connects at the manifold where the map sensor gets its feed.
If you have all that connected properly you should get a vacume, if not your engine is knackered or your cambelt is on wrong.
James

[possel]

i have a apexi avcr which is plumed into the map sensor and that reads fine tho? could it be down to a faulty map sensor? just double checked all the pipes and they all ok

[3S Service Centre]

ok so thats very odd, if you have a good reading from the map sensor I assure you, you have the line to the fpr plumbed wrong somehow, you need to get me some pics.
James

[possel]

also i have noticed something else, when the engine is turned off the guage on the fpr drops to zero, shouldnt it hold the pressure in the fuel rail?

[3S Service Centre]

Fuel rail pressure should hold for a short while and then slowly drop off.
James

[possel]

it goes to zero in 10-20 seconds? also hear a creaking noise (when the engine is hot) coming from the fuel rail area and because of the loss of pressue thought it mite be a leaking injector seal/injector

[3S Service Centre]

dude can I suggest you get your car to kent car craft who know mr2s fairly well. When it comes to fuel systems there should be no guess work and certainly no strange goings on that your experiencing. The fuel system is not to be messed with, small issue can end in engine failure or engine bay fires, you need some assistance with this matter.
James

[possel]

yeah very good point espically as it took me 6 month to rebuild the thing. thanks for your help much apricated

[3S Service Centre]

no trouble.

[T.F.S.]

im not too far from you in gravesend, you are welcome to pop down and ill show you where it connects mate

[possel]

iv got all the vacumes running fine now, just to check what duty should the injectors be running at? according to my apexi avcr there runnig at 85% on tickover???

[3S Service Centre]

85% on tickover is silly dude. There is something very wrong.

[T.F.S.]

if it really is 85% i doubt it would tick over?

[possel]

just under 85% its now around 83% iv reset the ecu and it went down a tiny bit, on full throttle boost (1.2bar) it goes to 85%. i did find out i had a faulty o2 sensor tho and changed that. i cant work any of it out, hope a good rolling road day mite help all these problems. unless anyone could shed some light on this subject???????