Hello there, I am new to this forum stuff, I know there is a ton of knowledge here. So I hope someone can help. Ok...I have a 22re out of a 91 pickup. It will run for a second then stop. It has good spark. I jumped the fuel relay and I can hear the pump humming. I unbolted the cold start injector and am not getting fuel coming out of it. I am getting fuel to the filter. Does jumping the b+ to fp rule out the air flow meter and the co relay from being the culprit. I checked the grounds a they look good. I am banging my head here on why it starts for a couple seconds then dies. Please help! Thank you in advance.

 

Actually, no, jumping Fp to B+ rules them IN.

When you go to start, the COR has one set of contacts made to allow the fuel pump to run long enough to pressurize the system while you crank. Once the engine turns over on it's own, the air begins to flow through the AFM, opening the vane in it, and causing the contacts in the AFM make, energizing the other set of contacts in the COR, and holding them energized, as long as the air is flowing through the AFM. If the air stops flowing through the AFM, for whatever reason, the COR contacts allowing the fuel pump to run open, stopping the fuel pump.

It's a very important safety feature, in case of an accident, stopping the fuel pump to not allow fuel to flow out of a possible system that's broken open. It's an important fire prevention feature.

You can ohm out the contacts in the AFM. If they make when the vane is opened, even slightly, the problem is the COR, or the wiring between the AFM and the COR. If they do NOT make when the vane opens, the problem is the AFM, and possibly the COR as well. You need to have a functional AFM before you can be sure that the COR is good or bad.

Do you have the schematics, or the FSM, so you can tell what pins on the AFM's connector to check to see if the contacts make correctly? Do you know where the COR is in the vehicle? I had the same problem in my 4Runner, and it turned out to be the COR. It cost me $65.00 at the dealership, after I showed them in the diagrams just where in the truck it was They hadn't the faintest idea what a COR was, or where in the truck it was.

Finally, if there's no fuel coming out the CSI, did you check the fuel at the banjo fitting going into the CSI, or just pull the CSI out and watch to see if it sprayed fuel? Only by checking to see if the there's fuel pressure available to the CSI can you determine if the fuel system is functioning correctly. Just looking to see if it sprays is not a valid test. There's any number of reasons why the CSI might not spray fuel during the start sequence.

Hope this is helpful...
Pat☺

 

You left out some important things!

Does it start and stay running while the fuel pump diagnostic jumper is in place? If it does you can unclip and disconnect the AFM and jumper the fuel pump connection there on the harness instead (it will run rich due to no signals, but it should run), if it runs you know the issue is the AFM and not the relay. Which we can further test by moving the jumper to the COR plug on the harness.

If you open the fuel system (banjo bolt) at the CSI port you will have to replace these crush washers!

A better check for the fuel flow is the fuel pressure regulator return line, where the fuel is returned to the tank at low pressure. You can put a vinyl hose here and plumb it into a suitable catch can, ideally something we can measure. It should flow close to 1 quart every minute while the jumper is in place. (You can pour a quart of water into a large clear bottle from a house hold measuring cup and Mark the fluid level. Alternately the plastic oil bottles are have 1q markings also.. For some examples.)

 

Thanks man! You're 100% correct, and I apologize.

Honestly, and I don't know why I didn't specify it, I thought that he had a pressure gauge on the CSI. I don't know why I wasn't more specific.

I also have a phobia about starting with the Fp jumper in. Just me. I just won't do it, because, in my little pea-brain, I am certain I've either forgotten something, or something broke on me, and there'll be a fire. I know the chances are almost nil, I just have an unreasonable fear of fire, after watching my property in Yuma burn 3 times.
2 1/2 acres, mostly left natural because I like it. Twice started by my neighbors, long story, and once by a local farmer's foreman burning off his fields. Now, fire scares the heck outta me.

Anywho, thanks for the additional advice!
Pat☺

 

First off. Thank you so much for your comments. So when I open the AFM with my hand I can hear fuel pump start humming and a click that I thought would be a working co relay. It’s coming up under the passenger kick panel, above the computer. I also can’t believe those Toyota guys never heard of this relay. I did pop off the banjo bolt at the CSI and there def is fuel getting there. No fuel pressure test, but it seemed good. Also there was no fuel coming out of the fuel pressure regulator while the fp to b+ was being jumped. It’s got me banging my head cause it will start for 2 seconds or so and then cut out. Could it still be the COR. That would be nice, cause I started looking for a computer, which doesn’t seem easy to find.

 

Your results are counter indicative, uhm sort of. Fuel at the filter, fuel at the rail, and nothing returning to the tank? Leans towards you're not getting enough fuel volume at the regulator, which means bad filter, crushed lines, clogged fuel pump "sock", a bad pump.

If you're feeding it starting fluid, passed the throttle plate, does it stay running until shortly after you stop spraying and reach atleast 500 rpm? (500rpm is important because it's around this point the ECU takes over firing the ignition, this tells you the NE signal is reaching the ECU and the injectors should be firing.)

You need to measure fuel pressure, and volume wouldn't hurt either. " seemed good " isn't a quantifiable test result we can compare against known good and bad rates and pressure.

You need both pressure and volume to meet specs. Lots of volume and no pressure (stuck open fuel pressure regulator) means the fuel will not flow thru the injectors when they open (it takes the path of least resistance). Lots of pressure and no volume (clogged filters, weak pump, damaged lines) means the fuel injectors start with a good flow then instantly turn to a lazy dribble or nothing at all.

 

Ok I’ll get a fuel pressure gauge and pull the return line coming out of the regulator and get back with some results. Thank you.

 

Ok I borrowed a fuel pressure tester from oreilys. I feel like an idiot because I have no idea how these fittings attach to the banjo bolt on the CSI. Am I a moron or do I need to get some sort of special 22re fitting.

 

It should have an adaptor included, that looks like the fitting where the fuel line enters the CSI, but without the fuel line. It should also come with a special bolt, like the one that connects the fuel line banjo fitting to the CSI, but longer. So it will fit through both fittings and hold the CSI on the throttle body, where it normally goes.

You should buy a bunch of the crush washers that go on top and bottom of the banjo fitting providing fuel to the CSI. A big bunch. You can't reuse them. You crack the bolt loose, even a little bit, to re-tighten it, new crush washers. You add the pressure gauge, new crush washers, a pair for each banjo fitting. You take it off, new washers. See the trend here?

What CO_94 recommended is another good test. Where you remove the hose on the bottom of the pressure regulator, and put a short hose down into a measuring cup of some sort. A pressure gauge only tells 1/2 the story. Yes the correct pressure is essential to allow the injectors to function correctly. BUT: you also need sufficient flow rate as well. Doing this test will tell you how fast, or slow, the fuel flows. The flow rate. You need to measure how much the fuel system provides the injectors in specific length of time. For instance, if the filter is partially clogged, you will have adequate pressure when measuring in a static condition, like just reading the pressure with the pump running, but the engine shut off. You won't have sufficient flow rate, however. Not enough fuel, fast enough, for the injectors to function correctly.

Does this help at all?
Pat☺

 

Thank you. I figured out the Pressure test banjo fitting. It was weird, the tester fitting only had a hole in one side of the bolt, the 22re banjo bolt has a hole on both sides of the bolt as well as through the middle. Does that make sense. So my tester was reading 0 cause it wasn’t able to flow through the bolt. I am going to try and borrow another one from a different auto parts store, now I know what the fitting looks like I can identify it before I leave the store. It is making sense to me why that pressure and volume is so important now for the injectors to fire. I will get back here with numbers in a couple days. Again thank you. You all are amazing.

 

Tried another parts store (autozone). There banjo bolt also only had 1 hole in it. I can’t get the pressure tester banjo bolt to line up with where the fuel comes in to get a reading. Am I missing something here.

 

You should probably provide some images we can reference at this point. What you have and how you are attaching it.

 

On the right is the pressure tester banjo bolt.

If you flip over the banjo bolts to the other side. You can see that the hole does not go the whole way through.

Pressure testing right here in the CSI.

 

Right. That's exactly the correct item for this application.

Run the tester's bolt through the circular fitting on the fuel pipe, and into the CSI, just like you would with the normal bolt. Imagine the large, hexagonal, area is the top of the bolt, where you would put the wrench on it to tighten it down. Remember to put the crush washers on, and to only torque it to the proper spec.

Then screw the actual gauge down onto the top, tapered portion of the bolt. A lot of people, I think, use teflon tape to help seal the gauge down. I swear I've seen that on other threads in here. Remember to turn it so it's visible! You don't want to get done snugging it into place, only to find out it's facing straight to the bottom of the engine or something.

Does this help at all?
Pat☺

 

Okay hooked it up.

This is the reading that got. Seems low, is that low enoough to not keep truck running for more than a couple seconds. This reading is with the fuel pump jumped in the diagnostic box. Thank you.

 

Sorry. The idiot I am I realized my battery was very low. Put a new battery in and my reading is around 25 psi now

 

I am getting no fuel coming out of the regulator return line while I am jumping the fuel pump

 

Back to front here.

You can see the annular ring in the banjo (fuel side) of the fuel line has a clearance? This lets the fuel flow out the hole in the fuel line and into the bolt regardless of the relation of the holes being lined up.

In the other two photos you can see the taper of the bolt and guage adapter, these should thread into the CSI in the same orientation ( head/guage to the "outside")

Can you trigger the pump and get fuel out of the fitting with nothing attached? If not your " clog " is upstream of the fuel rail or the pump is trashed (assuming the wring is ok).

Ok so you can work your way backwards from the injector and break loose each joint until you see fuel flow (at a cost of ~$5 per joint for new crush washers) or from the pump towards the front..

One common trouble shooting method is to "split the difference" this means you find the center point and start there. This will tell you if your issue is upstream or down stream and cut your trouble shooting steps in half (in most cases)..

So crack the supply side of the fuel filter open and check for flow then pressure. If you have pressure here move the guage to after the filter (fuel filter output or fuel rail input) you'll.find the filter is trashed or the supply line is damaged.
​​​​​or
You'll find the problem is the other direction. So you'll proceed to the tank and test there. I'd your pressure and flow are there you need to replace the tank to filter fuel line (hardlines, softline or both) this might be something you can fix with solvent and or compressed air (these lines are subject to cloging due to rust, the moisture in the fuel from ethanol, and physical damage.)

TLDR, pick a spot and.test your way in the direction of the issue.

 

Sorry responded to an out of date thread view..

Yeah that's way low combined with nothing going back to the tank you've located a fuel supply issue for sure. You will have to continue testing to determine the cause.

Just a quick tip if you don't have a good "battery box" you can hook up jumper cables from a running vehicle and get a bit more testing done with out a lot of concern over " battery voltage ".

I expect you're going to find both some rust , gelatine, and a clogged fuel pump sock all of which may have over worked the pump..

 

i appreciate all the knowledge and help you all have given me. I guess I got a plan now. I will reply back when I finish up with this process. Thanks again. Hopefully next time I reply I will have this truck running.