Timing belt,WP done with new distributor cap, rotor, spark plug and wires. Injector were change out from eBay (recondition oem with new seals, no leaks )
running fine for about 300 miles and last week is was not happy at traffic light
I did change out the old duralast fuel filter yesterday and put a new duralast fuel filter
Still have the problem
no problem idling on neutral.
should I adjust the air flow at the top of the TB?

 

Frequently, not always but frequently, this problem is caused by the idle being set too high.

The ECM has a circuit that cuts the injectors off when the RPM is above about 1000, or 1100, and the brakes are on. They figured, if the brakes are on, but the idle switch in the TPS is closed, you must be slowing down, and don't need the engine above spec idle, so it cuts off the injectors, until the engine slows to below the preset limit, then allows them back on. The idle goes high again, the ECU cuts them off, etc, etc.

Once you got done replacing all those parts, did you ensure the timing and idle were set according to the FSM? The idle should be about 800, IIRC.

BTW: If you go to adjust the idle, and have never checked it before, you might want to think strongly about replacing the little o-ring on the idle adjust screw. After 30 some years, the rubber degrades, gets brittle, cracks, and so on, and can let too much air through, making adjusting the idle a hit-n-miss proposition. Most auto parts stores, and even Harbor Freight, carry o-ring kits that have the right size o-ring for this application.
Just screw the idle adjust screw all the way down, counting the turns it takes, then back it all the way out. That way you know where to set the screw to at least get close once you've got the new o-ring on. Then you can adjust the idle correctly.
A small note: I've found that a thin layer of Vaseline rubbed onto the o-ring prior to installation will permit a better seal, and make it last longer once it's in. Works for all o-rings and other rubber parts.

Of course, if your idle is set correctly, disregard all my babbling...
Pat☺

 

Is this happening with a warm engine only?

 

Yes. Only on warm engine

 

22re?
I have a similar problem but mine comes up if I leave the truck in a parking lot and then come back and start it. Idles erratically btw 4 to 500 for a while. Im guessing its a heatsoak issue either in the ignition circuit or air/fuel sensors.

 

It is a 3.0

 

Sorry if not helping OP, but I had something similar with my 22re and cleaning out the throttle body cured it up for some reason. Why or how? I don't know. The TB in these trucks gets nasty AF and I think it may lead to clogged vacuum ports or something?

 

Yes, it can lead to clogged vacuum ports every easily. Especially the three small ones front top. EASY to fix. Most carb cleaner spray cans come with a small, red, tube, that will fit into the ports just right. A short shot of cleaner will do the trick. If the cleaner sprays back out of the port. it's probably clogged up. Give it a short snort, let it sit 5 or 10 min, then try again. Keep it up until it's not spraying back out of the port. The larger sized ports, like for the PCV system, will probably never clog, but it can't hurt to check them. A short puff of air into the hoses that go onto them will tell the tale.

Most of the crud in the TB is from the EGR system. It lets some nasty gasses back into the TB, and thus, it gets dirty AF, as you say If the air going into the front of the TB, through the big tube from the MAF, is getting the TB dirty, you need to use a better air filter.
Personally, I got a K&N filter that is a drop in replacement to the OEM filter, and it's worked well for years. Maybe 25 years now? I clean it every summer, and I get no dirt, dust, or other nastiness, through it. I had in Yuma, Az, for 15 years or so, and that is one DUSTY place. One of the worst air qualities in the US, due to all the farming and other agriculture. They kick up some DIRT when plowing, discing, and so forth. If the K&N stops the dust and other crud you get off-roading in Yuma, or even just driving around, it will keep anything out. Just me...

Have fun!
Pat☺

 

You do want to be careful about exposing the TPS to carb cleaner.

 

Can you elaborate about be careful on the carb cleaner on TPS?

 

Ooops

 

A catch can/ oil separator for a PCV system will stop the crap from going into your plenum. You can run two of them and cover the TB as well.

 

You don't want carb cleaner IN the TPS. Be careful about spraying carb cleaner anywhere that it can invade the TPS. Like don't spray carb cleaner in such a way that it gets onto the the throttle plate shaft. Especially the TPS side. It could flow into the TPS. A bad thing.

I've used carb cleaner in the three vacuum ports on the front-top of the TB several times. But very, very short shots of the stuff, and I opened the blade as wide as it goes, and stuffed a couple rags into it, so any carb cleaner was absorbed when it came through those vacuum ports. I also put a couple rags over the TPS, so any back spray out the ports got absorbed. I've also used carb cleaner on the other vacuum ports, with no problems. Just me, though.

I guess you could just use a piece of thin, stiff, wire to clean out the vacuum ports. I just wanted them clean-clean, if you see what I mean.

You could also remove the TPS, I suppose, and move it out of the way, and cover it with several rags to prevent accidental intrusion. Just have to align it properly when you re-install it.

Have fun!
Pat☺