So i went out to do some more testing today, and i think it really might be my brand spanking new fuel pump.

I have thought it is getting louder and louder since i installed it but just brushed it off, well i started really listening to it and you can hear it outside the car louder then the exahust (which has a leak BTW). Now i know i have never heard of a pump being that loud and working in my time other that a few warblo (sp?) but even they are not that loud.

Plus that would explain why this problem keeps getting worse, the pump must be going out.

I tried flooring it while idling and it would do the exact same thing every time.

Floor it = normal rev to 5500rpm, then it stops there and stays at 5500 for a second, then slowly drops to ~4500rpm where it starts running real bad and jumping around by +/- 500rpms.

So anyone got any idea what that could be? my best guess at this point is that it goes to 5500 on the built-up pressure in the fuel line. Then the pump can only pump enough fuel for 4500. but that could be way off.

I think tomorrow i am going to take the pump back and exhange it, it should not be that loud no matter what, that is outragesly loud.

 

Ok, found the problem with the high-rpm power loss, it was the fuel pump, well kinda:




As you can see the sock was clogged and my gues is that all that junk is what illed the pump (yes, it is going out, way to loud and runs rough).

So i then looked into the tank and saw this laying of junk ALL over it, so i am swaping the fuel tanks between the cars. the other one is clean inside. The worst part is i JUST filled the tank, there goes $40!

Oh yeah, i found this fuel pump in the other car:



The PO had swapped the fuel pump to run a turbo engine, any idea what pump that is? i might just use that and return the one i bought.

 

That would do it and seem like a Vac leak!
I think you just diagnosed your problem. Change out that rusty tank, chang your fuel filter and bled the line before you hooke it back up to the engine to get the crap out.
If that other fuel pump will plug into your harness, just use it. It's porbably from a turbo car, or a replacement.

Good Luck!

 

Yep, just got the tanks swapped over and started right up and seems to have fixed the high-rpm problem BUT i then started smelling gas in the engine and turned it off real quick.

Turns out my PD is leaking, so i am grounded until i get that fixed.

Though the high-idle was not fixed, i do think I might know what the high idle is.

SO, how should i fix the PD? I happen to have an extra S5 fuel rail here (was sent one by mistake). But when i tried to install it before the fuel inlets/outlets were backwards. Anyone know if that can be made to work?

Or should i just go to the banjo bolt mod? If so where do i get the parts? quickly and cheaply?

Also, while i have both cars on jackstands i tested the diffs again. The 87 is for sure an open diff, spin 1 tire the other spins the other direction.

On the 86 though, if i spin 1 tire the other does nothing. and yes the main driveshaft is being held still. Does that mean it is a broken LSD? If so, can they be rebuilt and how much and how easy?

 

I say switch to an S4 rail and grab a banjo bolt = PD fixed!
There are numerous part outs in the FS section, should be able to locate the necessary parts there.

 

No, i already have the S4 rail, that is what is leaking. I ALSO have an S5 rail laying around.

Where do you get the parts for the banjo bolt mod?

 

Ohhh, I must've misread. Thats easy then, just unscrew leaky PD, grab the banjo bolt from another S4 rail, insert in place of PD and you're done.

I found mine in a junk yard, but you could order a bolt w/ the right thread and pitch if you can find that info. I know its's on the forum somewhere....

When my PD failed (epically) I took that as an excuse to upgrade to a full steel braided fuel system lol.

 

Thats what i was afraid of, that means waiting for shipping which means i can't get this car drivable for almost another week.

I was so hoping I could get this finished and running right so i could get it inspected this week. oh well.

 

You could take the rail down to the auto parts store or hardware sore and cross your fingers...

 

I plan to try that tomorrow and see but i am not hoping for much. We will see though.

 

When you take the PD off if the little screw is still there you could just screw it back in and use some loctite on it. The screw backing out is what causes it to leak.
You coudl do that temporarily until you got a new part.

 

i think that sock is way worse than mine
mine is just dead and there is to much rust on mine
as for my tank.
its rusty planning to clear that out by the end of the week

 

Actually the screw on the PD DOES NOT cause the leak. i forgot the site but there is a site showing exactly how it works and is clealy shows the screw is not the problem. in fact trying to put it back in will ruin the PD most of the time.

Jut FYI, i thought the same as you until i did more reading on the subject.

That sock is WAY worse then the old one in the other tank. The one in the other tank had been there for who knows how long and it was basically clean.

The clogged one had been there for maybe a week.

 

whats that sqaure box thing attached to the rod?
whats the purpose for that?

 

Do you mean the float? That is what tells the gas gauge how much gas you have.

 

oh i didnt know that

but i just forgot to ask you, how about the straight rod going down wrapped in wire with the small cylinder thing in the end?
whats the purpose for that

 

That i don't know exactly, i could not figure it out either. It was connected tot he float box so my guess is it has something to do with that.

 

is there anything i can do if the bottom cushion, like the rubber on the bottom to hold the fuel pump is like deteriorating, any alternatives?

 

Well if you get a new pump it will come with a new rubber mount., if not then i don't know if you could buy just that piece or not, you could try a mazda dealer.

 

oh thanks..
you think i can grab the fuel pump out of a b2200 mazda truck?
its carb. but the fuel tank looks pretty much the same

 

I highly doubt it, carbs cars don't need as much fuel pressure so i doubt it would pump enough.

I actually have a BRAND NEW fuel pump now after exchanging the bad one and deciding to use the pump out of the 86. $90 and it is yours, costs me $130 + tax

 

thanks..for the info
my friend told me i can use an electronic fuel pump
but its gonna be independent and have to install a switch for it.
im trying to be money effecient
but i get what i buy though.. lol

 

Ok, so I am going to have to pull the intake off anyways to fix the PD (got a banjo bolt on order from mazda, should be here in a day or 2).

So while i am in there i figure I might as well go a little deeper and fix the stuck Aux port on the front rotor.

My question is what parts do i need and how to do it? Mazda wanted $120 for the sleeve, sorry but that is outrages. anyone know exactly what i need of if i could fix it after i take it off?

I also am going to replace all the injector o-rings and seals while i am in there to make sure those are not the problem with the idle, and put some RTV on everything when i put it back together, if that don't fix the idle i don't know what will.

Anything else i should do while i have the intake apart? I am going to see if i can find a local place that will clean the injectors while i am at it.

 

Are you sure it's the sleeve thats stuck? The actuator could just be seized. Pull of the actuator and see if you can rotate the sleeve. If the sleeve is seized, you don't have to take off the actuators, just pop off the LIM and pull the sleeves out. Clean them and use whatever type of grease the FSM specifies for them. Pop them back in, put a new LIM gasket, put the mainfold on and you're done.

 

The actuator is fine, i used my air compressure to test both of them and the rear works perfect, the front tries to move but the shaft won't move.

i tried hammering it a little and just bent the shaft a little (if i take it out i am pretty sure i can fix it, it is just barely bent).

So they can be cleaned even when jammed? that would be great. i have the top of the engine off anyways while sending the injectors out to be cleaned and doing the banjo bolt mod. So i want to get all of these things under the intake done this week.