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2.9L timing help


I took a long screwdriver with the truck running and can hear all 6 fuel injectors firing.
 
. Spark plugs are black and smell of gas (running rich). There is a bad backfire.

If you still have this, it looks like those plugs are being drowned by fuel. A fuel fouled plug will not fire. It would also explain the backfiring, there is so much fuel that raw fuel is entering the exhaust system and firing off when it hits the hot components, making the loud backfiring in the exhaust system. What would happen if you put some of the old injectors in those cylinders? It may not fix it, but you might have different symptoms. If you do, you know there is something going on with the injectors.
 
Is it possible the new injectors are the wrong size?
 
FP is at 44.

How did you get your pressure number? It should sit at about 30 at idle and jump up to 35-40 if you crack the throttle open (low vacuum.)
 
It sounds like the fuel reservoir broke and you removed it, and then replaced it with a fuel filter (which isn't really necessary there) and lines to bypass the fuel reservoir. Correct? The fuel reservoir serves a purpose. The low pressure in-tank pump pumps fuel to the reservoir, and the frame mounted high pressure fuel pump circulates fuel from the reservoir to the fuel rail, then back to the reservoir and back to the fuel rail, etc, etc. Will it work fine without it? I've never tried, but I have doubts.
The only way I personally would remove the reservoir is if I also removed the frame mounted high pressure pump, the in-tank low pressure pump, and did the high pressure in-tank pump mod.
As far as injectors are concerned, I first bought some refurbed injectors that didn't work very well. I ended up getting new Accel injectors and haven't had any issues in the past two years.
But before installing the new injectors I acid washed the fuel rail to remove any corrosion that may have been plugging up the injectors.
And I understand that using a silicone based lubricant on the injector o-rings can clog the injectors.
 
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The stock injectors are between 14-15lbs. The later model 4 hole injectors didn't work well with my Ranger, and I have read of others having issues with them as well.
 
I am heading to the junk yard tomorrow to pull the original fuel system and original air box. I am going to pull the injectors as well. The injectors I got were from rock auto and do not have a fuel rating I can find.

You are correct about the fuel canister. I put a larger fuel capacity fuel filter but still isn't the same size. Then ran new fuel injector line from the tank to the filter to the pump then up to the FPR.

I used a fuel injection pressure gauge with the vehicle running at idle I got 44psi.

These are the injectors I got (could afford). https://www.rockauto.com/en/moreinf...UH/OGYir1aos7oVHUus5JMSYlI3rotRLlbYlzUK7Yj+iT
 
I couldn't find anything on those injectors either. Before I bought the new injectors I bought an injector cleaning tool kit from Amazon that worked fairly well using Berrymans B12 #0117 (the good stuff). The good thing about the injector tester is that I was able to remove the upper intake and the fuel rail with the injectors still connected, slide an oil drain pan between the fuel rail and the lower intake, pressurize the fuel system, and cycle the injectors one at a time to see if they were clogged or if they had a good spray pattern. The Berrymans cleaned the OEM injectors fairly well, but there was still a slight hesitation, so I bought the new injectors and that completely solved the problem I had been having (poor acceleration, bogging, bucking, etc).
Before buying anything else, I would pull the fuel rail with the injectors still connected, and use a shallow oil drain pan, etc, and apply voltage to each injector with the system pressurized to see if all of the injectors are working or not. I forget what voltage to use. The tester just connects to the battery, but it's intermittant (it pulses fast or slow). I recall reading that a 9v battery would work also. The OEM fuel lines to the fuel rail should be long enough to get a drain pan under the rail (I put an old T-shirt in the drain pan so the fuel spray wouldn't bounce off of the pan).
Rebuild kits are available for the OEM injectors if you are successfull with cleaning them.
 
Did you pull the reservoir and replace with a filter. just by pass this, the filter is further up in the frame toward the engine bay.
 
So today I got a new Fuel injection gauge off the truck and not the crappy Harbor Freight one I had. plugged it up and started the truck and bam! 30-33 psi of fuel. Do you think this is due to the fuel canister missing and me straight running it? Also I can hear both fuel pumps running.
 
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So today I got a new Fuel injection gauge off the truck and not the crappy Harbor Freight one I had. plugged it up and started the truck and bam! 30-33 psi of fuel. Do you think this is due to the fuel canister missing and me straight running it? Also I can hear both fuel pumps running.
What's wrong with that? The guy in the book calls for 30-45 psi as normal.

The only problem you will run into by deleting the reservoir is when the tank get's low, you will have fuel starvation problems when going around turns. These early systems do not have a baffling system in the tank. They used the reservoir to smooth the fuel supply out when the fuel pump in the tank starts sucking air momentarily.
 
I'm a NEWB here so take this with a grain of salt but here are my thoughts:

It sounds to me the problem is related to timing and not fuel.

1) For us 86-88 2.9 guys the ECM uses our knock sensor to dynamically adjust timing. If there is no knock sensor input, the ECM limits total timing around 22 degrees (plus or minus a few).
2) static timing should be 10 degrees.

Check your timing with the spout in, it should be about 22 degrees at idle. Rev it a few times and it will not move much at all. Pull the spout and your timing should snap to 10 degrees and not move (even if you rev it). If that happens (timing locks at 10 degrees when you pull the spout), I think your TFI is fine. Then run KOER and see if you get a code 25. If you do, you have a knock sensor problem (or the wiring/grounds associated with it). If you don't get a 25, I am in left field.
 
So, where is the knock sensor located on the 86-88 2.9L ? ranger
 
Directly above the starter on the driver side of the block. There should be a 2 wire connector going to it and another un-used connector with one wire dangling next to it.

The connector on mine was SUPER brittle and absolutely caked in grime so be careful if you open it up. Someone mentioned above that it's in a blind hole and that's true. You can just pull unscrew it. I think I used a 28mm socket? I have had a bear of a time find a replacement for both the sensor and the connector so be careful with it.
 
would be easier to take the starter out? Where did you find replacements?
 

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