Need to know where VACUM to FPR comes from?!!(straight neck)

hgallegos915 · Post by **hgallegos915** » October 13th, 2005, 3:56 pm

Ok my car has no egr..so that elaves the egr out.. I know if i conect it to vacum from my intake manifold it will block the regulator causing a fire hazard again.. Im looking at the shop manual and it seems toi go to brake boostet but wait.. that goes to the im... Im lost here..anyone got a straight neck? maybe im reading it wrong... it seems to go to a solenoid that was near the k8 egr solenoids..

hgallegos915 · Post by **hgallegos915** » October 13th, 2005, 5:46 pm

called prc solenoiud valve..i know it goes to the im now..but that prc splenoid valve..what happens if i by pass it?? bad?

Rick Johnson · Post by **Rick Johnson** » October 13th, 2005, 7:15 pm

Are you asking about where to pull vac off for the FPR? And the solenoid that you are refering to is it the FPR solenoid? I don't know about the kfze's but I know the ZE's don't use one, just hook the FPR straight up to vacuum. I'm not sure where the nipple is on a straight neck the ZE curved neck has one like 4 inches from the FPR. There should be a few ports on the back for cruise vris etc you could always tee off one of those if need be. I don't think you need the FPR solenoid on a J-spec motor... I don't know why it's there on the Us-spec... anyone care to enlighten me...emissions related?

EDIT: Just as I clicked post I had this thought, I think it is emmision related, I think it may work in conjunction with the purge solenoid which purges the fuel vapour from the evap can? so it adjusts the fuel pressure when it purges into the manifold? just a thought

jschrauwen · Post by **jschrauwen** » October 13th, 2005, 7:30 pm

Rick Johnson wrote: I don't know about the kfze's but I know the ZE's don't use one, just hook the FPR straight up to vacuum.

Rick, are you guessin' on this or know for a fact. I hope I didn't chase my tail for nothing this past winter trying to sort that out. The PRC solenoid is supposed to richen the mixture for about 120 seconds when the engine has been re-started after it has already been running at normal operating temperature.

dewthis · Post by **dewthis** » October 13th, 2005, 7:46 pm

For a ZE there is a nipple on the side of the #6 runner to hook the FPR up to. Its right there next to the stock location of the FPR.

hgallegos915 · Post by **hgallegos915** » October 13th, 2005, 7:53 pm

yeah its there so i dont need the solenoid? it does have the nipple there and it is a jdm ecu and engine. I sorta lowerred the idle i have no idea how..fixed vris and running good.. the idle will sometimes go to 1.3 and the down..adjusted tps and i sorta got it working...i think. i should be testing it tomorrow for work. I dont know why my last fpr crapped out and blocked fuel trying to get back into the tank.

dewthis · Post by **dewthis** » October 13th, 2005, 8:54 pm

You don't need a solenoid.

lakersfan1 · Post by **lakersfan1** » October 13th, 2005, 8:54 pm

You put it the same place that the FPR solenoid was connected to before the engine swap. You're just eliminating the FPR solenoid in the chain when you go to the ZE ECU. I also believe the technical proper place is the #6 runner, but IMO vacuum is vaccum.

Rick Johnson · Post by **Rick Johnson** » October 13th, 2005, 11:10 pm

jschrauwen wrote:
Rick Johnson wrote: I don't know about the kfze's but I know the ZE's don't use one, just hook the FPR straight up to vacuum.
Rick, are you guessin' on this or know for a fact. I hope I didn't chase my tail for nothing this past winter trying to sort that out. The PRC solenoid is supposed to richen the mixture for about 120 seconds when the engine has been re-started after it has already been running at normal operating temperature.

I know that for a fact, my curved neck ZE came with the FPR hooked up off the #6 runner - no solenoid. So your saying on the K8 it's for richening the mixture on a hot start? interesting I thought you would want it leaner on a hot start, don't 4 stroke dirtbikes have a hot start switch/handle and it leans it out? I thought you want it rich on cold starts hence the need for a choke, or "coldstart" injectors found on the euro cars....

vozaday2000 · Post by **vozaday2000** » October 13th, 2005, 11:25 pm

ok all i know about the prc is that the klze's do not come with the prc selinoid. but the k8's do so most people (like me) include the prc selinoid in with the swap. on the klze's they have the 6th runner straight to the fpr whereas the k8 has the 6th runner branching off to the prc and the egr selinoids. then from the prc the vacuum line runs to the fpr. there is a diagram some place in this forum. during a hot start the ecu sends a signal to the prc closing a valve to the intake runner and getting rid of the vacuum between the fpr and the prc by opening it up to the atmosphere through a small air filter. so my guess would be that during a hot start it alows the engine to run rich. i don't understand the logic behind the engine running rich during a hotstart but that is what i understand.

vozaday2000 · Post by **vozaday2000** » October 13th, 2005, 11:26 pm

and no you do not need the prc. i just bypassed mine since it is shot. i still left it hooked up to the ecu though.

hgallegos915 · Post by **hgallegos915** » October 14th, 2005, 12:32 am

ok so all k series engines have the same fuel pressure regulator? even klze?

vozaday2000 · Post by **vozaday2000** » October 14th, 2005, 8:54 am

yes i believe they all have the kl01 fpr but i could be wrong on this. i will look at my klze fpr today but i know the k8 fpr is the kl01

ikarus1 · Post by **ikarus1** » October 14th, 2005, 5:01 pm

The PRC circuit not only helps out with hot-start, it also smoothes out the idle a little bit. Mine was on the fritz when I bought my 626 but a cracked vacuum line was the culprit. I have a solenoid if anybody needs one.

Rick Johnson · Post by **Rick Johnson** » October 14th, 2005, 11:00 pm

NVM theres to many variable to what i had posted.