93 4.0 black smoke and rough idle

[hunter29078]

http://ppl.ug/hYHXMaHc-gU/

Pic of throttle body

 

[RonD]

That would explain the smoke, change that trans vacuum sensor, lol.

Blow out all the other vacuum lines as best you can.

Hot spark may have been burning it better but the oil will still foul them and pretty quickly, and you will be back to where you were.

O2 sensor should also be pulled, and probably changed from oil fouling.
Cat converter will have a shorten life as well.

 

[enjr44]

Well, the top end should be carbon free after washing with ATF.

 

[hunter29078]

Yeah nice and clean.

Turn our cat has got to come out to get modulator out, so its going to stay in today. However I unhooked the line from the modulator and ran the engine to see how it would idle without the atf. Idles much better but then begins to flood. A little black smoke, so I did the clear flood routine and it was running. So I pulled fuel pump fuse, and ran it it dry and tried again. It must be pouring from the injectors because it not only turns over it cranks up and revs to about 4000 rpms.

The plugs, wires, atf must have masked this test earlier, the fuel pressure was decreasing rapidly and at the time wasnt sure if it was the fpr or check valve. Could the atf have been thrown up into the injectors and caused them to screw up? This truck was driven around for some time in this condition also sat a lot.

Anyhow, anyone got recommendations on injectors? The motorcraft ones have gold plated o-rings. Found a set of bosch on ebay for around $100. That sound about right? The red ones are stock correct?


Thanks.

 

[ghost_rader]

did you ever get this issue figured out? if not i have a sugestion. on the 93-94 rangers with the 4.0, the two o2 sensor plugs are on top of the bell housing. they will both plug into the wrong plug. try switching the left and right sensor plugs. i had this happen to me a long time ago and drove me mad for a frw days till i realized what happened.

 

[Angie]

Also it is weird because the black smoke stopped when I changed plugs and wires, so apparently ATF doesn't blow smoke out like oil or a rich condition


Trans fluid is strong WHITE SMOKE when it is burnt by sucking oil through a busted trans diaphragm. Stick a vacuum gauge onto the intake tree, use a long rubber line and pass the line through the fire wall and go driving and see what the readings are through different situations. you will learn what happens when you have a broken diaphragm, (extreme hard shifting too) and you can also place a 3 dollar clear plastic filter on the vacuum line that feeds the trans air line and when she is blood red you will know you have trans fluid in the intake.

trust me I can write a book about blown trans diaphragms.