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No Start after fuel injector install


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Starting a new topic concerning my retarded fuel injector, supposed upgrade.

 

Everything is back together I think. I have looked for any loose connectors, hoses, vacuum lines, etc. Image posted of what I found, but I'm not sure what I found wasn't already as is.

 

Uploaded audio of truck trying to to start. Never catches, just goes round-n-round.

 

Checked CPS, looks fine. Connection seemed okay.

 

Ran fine before I screwed with it. Just don't understand engines, I guess. Should I just clean the stock injectors and put them back?

 

Really need some guidance here.

 

SPECIAL NOTE: If, like me, you think it would be cool to work on your truck, but, like me, you're a Greenhorn. I highly suggest buying the parts and having someone who knows what the frick they're doing to put them on.

 

This is ridiculous!

 

 

Not easy 5.jpg

Not easy 6.jpg

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56 minutes ago, cruiser54 said:

does it even TRY to start?

 

Unplug and plug back in your CPS. Make sure the line from the throttle body to MAP sensor isn't messed up. 

Yeah, it turns but won't catch. I checked the CPS. I don't think I checked the MAP to the TB. I'll look at that after work.

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2 hours ago, NC Tom said:

I'll check. What would that mean?

 

if it tries to fire, that means the problem is in the fuel delivery.  if it doesn't try to fire, that means spark is gone.

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2 minutes ago, Pete M said:

 

if it tries to fire, that means the problem is in the fuel delivery.  if it doesn't try to fire, that means spark is gone.

So, more than likely the injectors are not working? I changed nothing else.

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Another easy test is to turn the key to 'ON' and make sure you hear the fuel pump. Then turn off and depress the fuel rail valve to ensure it built pressure. If so, then either your injectors aren't firing or you have no spark. You can also remove a spark plug to see if it's covered in fuel. 

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Like Pete mentions, pour a small amount of fuel into the TB and see if it fires (or a very short blast of starting fluid).  Are the plugs wet after cranking like that?  

 

Assuming you got all the injector wires hooked back up to the correct injectors.  Each plug has a different wire color so you can check.  The harness pretty much stays in place once disconnected, but the middle cylinders can get messed up/swapped if you're not careful.

 

#1 - light blue

2 - light green

3 - tan

4 - yellow

5 - white

6 - brown

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10 minutes ago, howeitsdone said:

Another easy test is to turn the key to 'ON' and make sure you hear the fuel pump. Then turn off and depress the fuel rail valve to ensure it built pressure. If so, then either your injectors aren't firing or you have no spark. You can also remove a spark plug to see if it's covered in fuel. 

Okay. The fuel pump is working, but I have not checked for pressure. On my list now!

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2 minutes ago, mjeff87 said:

Like Pete mentions, pour a small amount of fuel into the TB and see if it fires (or a very short blast of starting fluid).  Are the plugs wet after cranking like that?  

 

Assuming you got all the injector wires hooked back up to the correct injectors.  Each plug has a different wire color so you can check.  The harness pretty much stays in place once disconnected, but the middle cylinders can get messed up/swapped if you're not careful.

 

#1 - light blue

2 - light green

3 - tan

4 - yellow

5 - white

6 - brown

Sure. I taped them before removing. But I'll check again.

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2 hours ago, NC Tom said:

Sure. I taped them before removing. But I'll check again.

 

Even with the connections swapped, there is a good chance it will still run (albeit somewhat poorly).

 

What injectors did you swap in and why did you do the swap?

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20 minutes ago, SoCalJeepComanche said:

 

Even with the connections swapped, there is a good chance it will still run (albeit somewhat poorly).

 

What injectors did you swap in and why did you do the swap?

Bosch 0280155700. I had leaks and figured I'd "upgrade" to a 4-hole.

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On 3/9/2023 at 9:04 AM, howeitsdone said:

Another easy test is to turn the key to 'ON' and make sure you hear the fuel pump. Then turn off and depress the fuel rail valve to ensure it built pressure. If so, then either your injectors aren't firing or you have no spark. You can also remove a spark plug to see if it's covered in fuel. 

Okay, I can hear the fuel pump, but nothing happens when the fuel rail valve is depressed. Before this work, I would get small amount of fuel and could tell pressure was releasing. Do I need to leave the pump running for a bit to build pressure after having the fuel rail off?

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1 hour ago, howeitsdone said:

If you leave the key 'ON' then it should spray out fuel when the schrader valve is pressed in. When it's off, it should mostly trickle out at a rapid pace. It only takes a few seconds to build the required pressure.

Key on, no spray.

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If you know for sure there is no fuel delivery/pressure but you hear the pump operate, it's time to pull the pump out and inspect it. My XJ did something similar to your situation, one day it just wouldn't start but I could hear the pump operate and a fuel pressure gauge at the rail port read zero pressure. The issue was a clogged fuel pump strainer, 5 bucks and a few beers later the XJ was back in business...

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