Tbi backfire through intake

[Rustjunky67]

UPDATE!!.....
So this afternoon checked egr system out good..... after putting it back together after testing according to book, this is what I got (video).....
Leaking injectors....
But truck running better than it has in at least a year..... was idling great..... everything looked great except injectors....I don't know what I did to cause it to straighten up but it did that's all I know lol......
then.....
I decided to crack open the oil filler cap and it immediately died and can't get a restart yet....

Here's link to video

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[Schurkey]

I decided to crack open the oil filler cap and it immediately died and can't get a restart yet....

Failed PCV valve, and plugged crankcase fresh-air intake?

 

[Rustjunky67]

Failed PCV valve, and plugged crankcase fresh-air intake?

Ok I'll check this...
What about the injectors trickling instead of spraying?

 

[Schurkey]

Buy only Top Tier fuel.

Dump a bottle of Techron Complete Fuel System Cleaner in the tank just before filling-up, for two or three tankfuls. See what happens.

 

[Rustjunky67]

Buy only Top Tier fuel.

Dump a bottle of Techron Complete Fuel System Cleaner in the tank just before filling-up, for two or three tankfuls. See what happens.

I plan to if I can get it running, but to do that is turning out to be quite the conundrum

 

[pressureangle]

Failed PCV valve, and plugged crankcase fresh-air intake?

Agree- cap off your PCV briefly and re-test. I can't think of any other thing that could cause a quit with the oil filler.

 

[Rustjunky67]

Agree- cap off your PCV briefly and re-test. I can't think of any other thing that could cause a quit with the oil filler.

I would think that the engine being that tight would be a good thing....I took pcv back out and it is free as any new one I've ever felt..... and it holds vacuum.....
Crank vent hose is clear as a bell....

What's got me so flustered is it ran so good with the injectors dripping like in the video... instantaneous throttle response that it's never had before...... and now can't get it to even start much less run that good... from one crank to the next it just makes no sense.... yet

 

[Erik the Awful]

Vacuum leak.

 

[Rustjunky67]

13psi fuel pressure between filter and TB....
Now no spray, dribble, nothing

 

[Schurkey]

Do you have system voltage at one wire to each injector when the key is turned to "Run"? If not, you've likely got a popped fuse.

When you have power to the injectors, install a 'noid light on one of the injector wire harnesses, see if it flashes. If it flashes, the injectors have signal to spray. If you have power to the injector, but no flashing--the computer is not commanding injectors to spray, or the wire harness is damaged.

Do you have spark? No injector spray, no spark = likely failed pickup coil or ignition module, or failed wire harness between module and ECM. Connect a scan tool and look for an RPM signal when cranking. No RPM when cranking = failed distributor parts, or failed wire harness.