Poorly running 89 2.9

[Mightyfordranger]

I will tell you here lately I am a big believer in that sea foam stuff. I have had several small engines that would not half run because of the old ethanol fuel messing the carbs up. I pour the sea foam in the tank, about 50-50 and IF THEY ARE RUNNING, it will slowly clean them out. They are usually running like new after about 20 minutes. I bet that stuff would unclog any fuel system if you could get it in there strong. Letting the fuel tank get low and pouring a whole can in there would probably break anything up in the fuel system.

Well I just filled it up too....dang it. I mean I can just pull em out and let them soak in some cleaner I guess over night. Or I'll price them at summit. And grab em I bet autozone wants an arm and a leg. I gotta get rims and tires for the thing anyway

 

[Paulos]

If you remove your injectors to try and clean them yourself, get a repair kit to replace the o-rings and micro filters. One of the other issues with the 2.9 fuel system is the fuel rail corroding on the inside because of the moisture in the gas caused by the ethanol (when the vehicle sits for a while). The corrosion can then clog the micro filters in the inlet side of the injectors.

This is about the strongest cleaner I could find at the time I tried cleaning mine, though the can says you don't want to get any on you (it's the GOOD stuff ). If you try it, make sure you get the model number that doesn't have the "-45" or "C" after the number (e.g. 0117, not 0117-45 or 0117-C). The toluene concentrate is far lower in the other two, but it's not as toxic, and won't clean as well.

When I cleaned mine it helped a lot, but I still had a slight bit of hesitation, so I bought these from Advance ($50 off with code SC22T3) and haven't had any issues for over a year.

 

[Mightyfordranger]

I ordered some injectors from summit. And some rims and tires too. Gonna head over there in the morning and pick it all up. Change it out over the next few days.

 

[rusty ol ranger]

I ordered some injectors from summit. And some rims and tires too. Gonna head over there in the morning and pick it all up. Change it out over the next few days.

I had weird issues i fought for over a year on my 87 2.9. It turned out to be injectors as well, but its always good to only go as deep as ya need to.

The injectors were actually a pretty simple job. When removing dont forget about the two screws holding the rail on that are hidden by the drivers side valve cover.

I didnt know they were there and thought the injectors were stuck in the ports, so i got out the prybar...ruined the fuel rail beyond repair.

Oh, also clean the hell out of the rail and check it for pinhole leaks

 

[Mightyfordranger]

I had weird issues i fought for over a year on my 87 2.9. It turned out to be injectors as well, but its always good to only go as deep as ya need to.

The injectors were actually a pretty simple job. When removing dont forget about the two screws holding the rail on that are hidden by the drivers side valve cover.

I didnt know they were there and thought the injectors were stuck in the ports, so i got out the prybar...ruined the fuel rail beyond repair.

Oh, also clean the hell out of the rail and check it for pinhole leaks

Ah thanks for the tip i prolly would miss those 2 bolts under the valvecover.

 

[Mightyfordranger]

alright. so I bought a set of injectors, TPS sensor, set of valve cover gaskets, and a set of intake manifold gaskets as well.
I haven't gotten to make the little fogger pump I found a video of up there do to not wanting to go into Walmart while a virus is afoot.
so look over this quick video I made when I just swapped the TPS before work, and I didn't do anything to teach it anything about the sensor position if any is needed tell me what you guys think

so it wont decelerate off a quick rev it takes a sec to come down. Also as stated before under load and a hard pull it will stumble a fall on its face for a bit then just come alive and take off like gangbusters.

but I do have a new set of injectors to put in they are accel brand.

 

[rusty ol ranger]

Change the injectors. Then unhook the battery for 30 minutes to "reset" the ecm.

Drive it normally for a week or two and see how it is.

 

[franklin2]

so it wont decelerate off a quick rev it takes a sec to come down.

A little bit of that is normal. It's an emissions thing, they don't want the engine really rich when you slam the throttle shut sitting still. When you are moving, it will shut the injectors off for a little bit and then as you get slower to a certain point it turns them back on. When coming up to a stoplight you can usually feel it decelerating and just before you start hitting the brake sometimes you can feel a little "bump" when the injectors are turned back on.

 

[Mightyfordranger]

A little bit of that is normal. It's an emissions thing, they don't want the engine really rich when you slam the throttle shut sitting still. When you are moving, it will shut the injectors off for a little bit and then as you get slower to a certain point it turns them back on. When coming up to a stoplight you can usually feel it decelerating and just before you start hitting the brake sometimes you can feel a little "bump" when the injectors are turned back on.

that's odd. because it gets so bad it will hold the throttle open at like 3k rpm. I was hoping that the new tps sensor would solve that part

 

[franklin2]

Since you replaced the tps have you reset the idle stop screw? The one you should not touch? Get the engine fully warmed up, the upper radiator hose should be hot. Then unplug the idle air control valve wiring plug. The engine rpms should drop very low, you can almost count the fan blades going by. If it's too fast back the screw out. If you back the screw out till it's not touching, and the engine is still idling (you should be able to make it stall out) you have air coming in somewhere else.

Get it turning slow, and then plug the idle air control plug back in. Don't panic, it will idle very fast. Take it out and run it, bring it back and cut it off. Restart it and take it for a spin again, and then bring it back and cut it off. Restart it again, it should idle a little fast and then settle down and be somewhat normal if everything is working.

 

[rusty ol ranger]

that's odd. because it gets so bad it will hold the throttle open at like 3k rpm. I was hoping that the new tps sensor would solve that part

That sounds like a vacuum leak. Unless your TB itself is sticking.

 

[Mightyfordranger]

Alright ill post up another video. Just got it all back togther with the new injectors and tps i wired a new plug for the tps too. Its got new vavle cover gaskets as well. Not that it makes a difference right now anyway.

But I'm not sure if I have the rotation of the tps right when I put it in. Because you have to rotate it some to get the throttle blade deal in the hole then spin it to line up the holes. Not sure if I did that correctly. It didn't resist rotation and I never felt a stop ya know.

But I'll have to get it out and let it get hot and do that reset franklin is talking bout.

 

[Mightyfordranger]

 

[Mightyfordranger]

Also that little pcv valve deal on the pass side valve cover. Its got 2 vac ports one runs to the throttle body area where does the second one go? It was just open so I stuffed a hose with a screw over it to stop any vac leak.

 

[franklin2]

I just went out and looked my 1986 2.9. The PCV valve has a large nipple for the PCV function. The small one was plugged off when I bought the valve new. They make these PCV valves fit more than one application, some applications do use the small nipple, several of my different engines don't including the 2.9 I have. When you buy them they are usually plugged off with plastic, and if you need the small nipple you have to cut the plastic off like you would for a caulk tube.

I was looking at your video. I don't understand what that line is for that comes out of the fitting, loops around, and goes back into the intake behind the IAC. I went out and looked, my 1986 doesn't even have a vacuum port toward the firewall behind the IAC.

I am assuming on the forward vacuum fitting, that rubber line you have wire tied to the air intake hose goes over to the MAP sensor? Does the engine stall out when you unplug this line? And the reason I ask about that other line looped, I can't tell where it goes or what it's for, but I have found when I start messing around with that vacuum fitting that the MAP sensor goes to, adding stuff to it, it will seem to starve the vacuum to the MAP, causing it not to run correctly.