dark scorpion

iTrader: (2)

Hello all,

I had recently just replaced the tbi fuel pump in my 92 bird with
a pump for a tpi fuel pump. My first question is with this be ok
for my tbi engine????
The second thing is I want to (more likely, need to ), replace
the fuel pressure regulator. My question here is do I need to
put a fpr that would normally go on tpi engine on my TBI vehicle,
or can I still a use a newer tbi fpr?
Needless to say my car is having fuel problems. Replaced the
pump and still having hard start problems (entire ignition system
is new getting spark and pulses). The next thing was diagnosing
fuel troubles.
What else could it be? ECM maybe????? I have had the car for
a year and a half and have only been able to drive it about a
handful of times before it started SEVERLY doing what it is doing
now. It used to start (after about 10 seconds of cranking), now
it will start (still after about 10 seconds of cranking), and then
die after about a minute. I know the timing is part of it and I am
going to tackle that before I mess with any other fuel component,
but I just want to try to get an idea of what I should do.
My main focus is the interchangelability of the fpr's. While I have
no doubt that you CANNOT put a tbi fpr in tpi engine, but CAN
YOU put a tpi fpr in a tbi engine.

Thanks!!!

Benm109

Replacing the TBI fuel pump with a TPI fuel pump is just fine. Most people here actually, me included, recommend installing some form of a higher flow fuel pump when the stocker goes out. The stock fuel pressure regulator does not have to be changed out, it will maintain the same pressure (or slightly higher pressure, depending on how much the new pump flows) as it did with the TBI fuel pump. The stock FPR will just return any excess fuel back to the tank. TBI and TPI FPRs are not interchangeable in any way, TBI FPRs will not work on TPIs and TPI FPRs will not work on TBIs.

Why do you think you need to change the fuel pressure regulator? Just curious. The stock FPR doesn't really go bad, but the FPR diaphram can go bad over time and leak. You can get a new FPR diaphram at pretty much any auto parts store.

If you want an adjustable FPR, you can just modify the stock one. All you have to do is remove it, drill out the center of the FPR, slot the factory screw, and then reinstall it. There's a tech article on how to do it on the main page, check it out:
https://www.thirdgen.org/newdesign/tech/tbi-afpr.shtml



As for the driveability issue, it could be any number of things. If the timing is really that off, I would fix that first. After that, it's time to check everything while it's running. First thing I would check for is vacuum leaks. Inspect all of the vacuum lines that you can find, and make sure none of them are disconnected, cracked, bent, or jerry-rigged. When the engine runs, try spraying carb cleaner around the intake manifold and base of the TBI unit while listening to see if the engine bogs. If so, the intake manifold gaskets or TBI mounting gasket are bad and/or leaking. You could also just check vacuum at idle with a vacuum gauge, should see about 18-21 Hg at idle if I remember correctly. Watch the injector spray at idle, it should be a nice conical pattern with an occasional drip. Check fuel pressure to make sure it's right, should be 9-13 PSI. Might also try removing and cleaning the IAC valve, there's a nice write-up at the bottom of the "New to TBI" sticky.

dark scorpion

iTrader: (2)

Well I think I need to change the FPR because I had always
thought that the car had fuel problems. Plus the fact that the
pump will prime and NEVER shuts off has me believing that the
pressure is the problem. I guess the easy thing to do would be
to test the pressure that way it takes the guess work out of it. I
always had a problem with buying a tool that I KNOW I wouldn't
use again for a while if at all.
Is what I am describing possibly due to the diaphram and not
the regulator itself?????
As for the vacuums I am pretty sure I checked for the ones that
go to the tb itself but I will go back and check for EVERY vacuum
I can locate.
Also, I noticed that the cowl (or whatever the thing is called) that
goes around the tb unit comes off rather easily. It looks like there
is a gasket that goes underneath it. Could this be causing a
problem?
Lastly, what exactly comes in a tbi tune up kit and would that
help my cause.
I am trying to eliminate ALL posibilities before I say it is the
ECM. I have been working on it from time to time and sometimes
it throws codes out then when I go back to work on it (most times
it is a week or so later), the code doesn't show up again. What's
the deal-e-o.

Thanks for the other suggestions though. Can't wait to try them
out and see if it runs any better.

Benm109

It's possible. The only 100% positive way to know, though, is to check fuel pressure. I know how you feel, having to buy a $40 tool that you'll probably only use a couple of times, but at least your not paying some mechanic do it, right? I don't know about you, but I'd rather spend my money on tools that I can use for the rest of my life rather than the labor fees of a mechanic .

Anyway, like I said, the regulator doesn't really go bad. The stock FPR has no real moving parts, and the only thing I could think of that would break is the spring in the FPR. But, if the spring did break, I would imagine that you would have very little to no fuel pressure at all. Usually the only thing that ever has to be replaced is the diaphram. But, checking the fuel pressure will let you know if anything is bad or not.

Here's a picture of the fuel pressure regulator assembly, not including the FPR diaphram. Keep in mind that the cone-shaped piece and screw are not removeable on the stock FPR (I have modified the one in the picture):


I am not totally sure what you are trying to describe. It sounds like your either talking about the air cleaner assembly (black round piece that installs on top of the TBI unit, houses the air filter, and leads up to the driver's side headlights with a plastic snorkel) or the gold spacer ring that installs in between the TBI unit and air cleaner assembly. Are either one of these what your talking about?

A TBI tune-up kit is basically just a rebuild kit for the TBI unit itself. It includes all the gaskets, o-rings, filters, etc. needed to refurbish the TBI unit. It also includes a new FPR diaphram. Unless your TBI unit is extremely dirty or is physically leaking, you probably won't need the kit.

Here's all the parts that come in a kit, the FPR diaphram is the piece in the lower right hand corner that's orange with a metal disk in the middle:


Are you disconnecting the battery at all during that time? Leaving the battery unhooked or pulling the ECM fuse for a while will make the ECM lose it's "memory", so to say. Do you remember what codes it would throw? Were they always the same codes, or different every time?

liquidh8

I dopn't want to hijack the thread but I have a similar problem.



I just bought a carter 5001 fuel pump. External mount. ( retrofit application) It is supposed to be 22 psi @ 50 lph. But I think I they packaged the wrong pump in the right box. I have a vafpr, all new fuel and return lines, no restrictions, and I have 28-30 psi @ idle, I tried everything. I even put the adjustable fpr back on and I can't turn it down. So I put my gauge right at the pump and it pumping 65+ psi. The pressure is just too high for the regulator to handle. I'm going back to work tomorrow and I'm ordering another pump to see if it is packaged wrong or if the one I have is defective. Let you's guys now tomorrow.

dark scorpion

iTrader: (2)

"I am not totally sure what you are trying to describe. It sounds like your either talking about the air cleaner assembly (black round piece that installs on top of the TBI unit, houses the air filter, and leads up to the driver's side headlights with a plastic snorkel) or the gold spacer ring that installs in between the TBI unit and air cleaner assembly. Are either one of these what your talking about?"

I believe its the gold spacer ring. I knew it wasn't the air cleaner
assembly( should have made that clear in the other post).

Guess I will have to bite the bullet and buy a pressure tester.
That way I will KNOW. But if it turns out to be the FPR, I will buy
that AND the tbi tune up kit as most of it will be apart anyway.

As far as the cosistent codes. Yes I had always removed the
battery (live in an area where while you are at work, people
will steal your battery). The one code that I had kept getting
was a 33 or something. Which ever one has to do with the MAP
sensor.

First things first though. Try to get the timing right and I can go
from there. But do you have any idea on what might make cause
the problem with the fuel pump allowing it to prime but NEVER
shut off?????? ECM??????????????? When the car did run, it
would go for a short while then feel like it was out of gas. Adding
to the diagnosis problem, my fuel gauge doesn't work so I had
always just tried to start the car and go to the nearest gas
station and got enough gas to get me home.

Benm109

There are supposed to be gaskets on the spacer ring, both where it sits on the TBI unit and where the air cleaner sits on it. Those gaskets aren't totally necessary, but it helps keep dirt and other particles from being sucked up in the engine. I've always used gaskets between them, mainly because of how cheap they are, $3. Any auto parts store should carry them, just ask for an "air cleaner mounting gasket", you'll need 2. If you get a TBI tune-up kit, you'll already get 1.

http://www.partsamerica.com/ProductD...pe=518&ptset=A

No, I don't. First things that come to my mind are a sticking fuel pump relay or a possible short to ground in the wiring, but I'm really not sure. A little later today I'll take a look in my factory service manual and see what it says.

Benm109

Didn't really find anything in my service manual, I'll keep looking though.

That would be the first thing to check, now that I think about it. If the car's extremely low on gas, it's not going to run good, of course. That might just be the whole problem right there. Just make absolutely sure you've got plenty of gas in the tank before you try starting the motor again or condemning any bad fuel-related parts.

As for the fuel gauge not working, I would suspect a problem with the fuel tank sending unit, either the unit itself or the float. It could also be the wiring or even the fuel gauge itself. If you want some troubleshooting guides for figuring out what's wrong with the fuel gauge, just let me know and I'll post what the service manual says.