troublesome 2.9L

[Dusty_Ranger]

so my dad has had his 86 ranger for 10 years now, and since day one its had this gremlin in the wireing/feul system, he a lisenced mechanic and been chasing it since day one and is tired of it so now im stepping up to hunt it down, the truck seems to be starving for fuel under acceleration, so its jerky and stumbly, the truck has new parts or known working units such as: fuel pumps, injectors, fuel filter, spark plugs/ wires, cap and rotor, i have swaped out the computer, with a known good one, ive done realays, grounds the next step is to swap the ignition coil and go thruogh the wireing, any other input would be welcome. the truck is a 86 with a functioning egr system

 

[Dusty_Ranger]

bump

 

[heptofite]

how are you diagnosing that it is starving for fuel?

have you replaced the throttle position sensor?

 

[adsm08]

dumb question, and seems to be my answer to every 2.9 running issue on this forum, but have you checked the O2 sensor?

Also, have you checked the MAP? Either of those could cause a fuel issue. I have a known good MAP from an 87 2.9 that I'll sell you cheap if you want to try that.

You could also try cleaning the IAT IAC, and TB, and checking the TPS (I also have one of those if I can find it).

 

[Dusty_Ranger]

i have all the know good replacement parts but ill try those and let ya'll know

 

[bcost882]

My buddy has the same problem with his 2.9L. does yours sometimes die with the clutch in and coasting?

 

[adsm08]

My buddy has the same problem with his 2.9L. does yours sometimes die with the clutch in and coasting?

He needs a TFI module. I have had this symptom on several separate occasions through out the years. It is invariably followed, anywhere from one to six months after the first occurrence, by a TFI module failure.

 

[kunar]

i would check the fuel shut off switch on the passengers side floor board. they are notorious for problems, either the switch its self or the connector that plugs into it. check it to rule it out...

 

[wrecking-crew]

a 2.9 with trouble? thats a good one. we own the most indestructable engines(heads dont count)

sometimes on the fuel cutoff (inertia) switch, the wires that are under the carpet wear the insulator off. it could short out the switch causing no fuel to the engine.

 

[bcost882]

thanks adsm08 i'll see if that will help

 

[adsm08]

thanks adsm08 i'll see if that will help

You know the easy way to get them out? Grab the $4 TFI module tool at advanced and slip it in with the distributor still in, then pop a wrench on it to break the screws free.

Remember to get that white goo on it good, those modules were notorious for burning up because they sit at the back of the engine, right between the exhaust manifolds, and get no airflow because of the intake. The heat sync gel is about the only thing that saves them.

 

[StreetRat]

~I have gots to post this~
'87 Ranger 2.9L Auto
In a way, there are two filters. Inside the fuel accumilator is a wix#33268 filter. Clogged to the gills! Previous owner changed it before also. Teeth marks on it.
Blew my mind, I did not know that and never heard of it. As in, any other posts, its not even mentioned, nor in Haynes book. But one of the first filters at Advance On-Line and Napa. Guess more truck owers should be aware of this lil' nugget.
Well, the parts store closed for today.

Check into it... Hopefully this will help others!!!

~All have a ~Merry Christmas~ All others ~To each his own~
Many Blessings...

 

[adsm08]

~I have gots to post this~
'87 Ranger 2.9L Auto
In a way, there are two filters. Inside the fuel accumilator is a wix#33268 filter. Clogged to the gills! Previous owner changed it before also. Teeth marks on it.
Blew my mind, I did not know that and never heard of it. As in, any other posts, its not even mentioned, nor in Haynes book. But one of the first filters at Advance On-Line and Napa. Guess more truck owers should be aware of this lil' nugget.
Well, the parts store closed for today.

Check into it... Hopefully this will help others!!!

~All have a ~Merry Christmas~ All others ~To each his own~
Many Blessings...

Yeah, I keep forgetting those are there too. They aren't generally meant to be serviced with the rest of the fuel system filters, and in fact, more than half of them, including my truck, aren't actually filters but screeners. The screens can clog up with a gel like crap that is dirt particles and fuel mixed together, and can cause a fuel issue. Also a bit of a pain to replace on 4x4s. Take the shield off, it won't save you any time trying to fish it out around, it just gets stuck.

Good call Rat.