84 B2, Idle issues. Runs fine at speed.

[Sparkman337]

I have a 84 B2, w/2.8L V6, 4X4, only 74K on truck. Most of the time when starting, even after warmed up. Truck idles rough and stalls. Once started Black smoke comes form tail pipe. When starts and runs normally no smoke from tail pipe. Have had ford look at it when I had Transmission Sensor replaced (wouldn't start in parK), they say it needs a EGR valve, TPS sensor, and a DPFE replaced. Looking at other posts, Should I replace the TPS and DPFE first to see if that clears it up? Also my Haynes manual shows that to replace the EGR valve I need to remove the Carb, is that right?

Any help with the issue would be greatly appreciated. Thanks for the info in advance.

John

[Ruffinit]

IF you have been through the carb tune up procedure in the Haynes or Chiltons manuals I would change one thing at a time. Most often this happens because the carb tuneup was not performed completely. As far as the EGR valve goes, I believe it is on a standoff on the front passenger's side of the intake manifold. Not the carb.

[Sparkman337]

I replaced the EGR and EGR Position Sensor on top. The EGR valve was stuck in that position. Must have been the original sensor. Truck ran fine for 48 hours then went back to rough idle and will not stay running. The EGR Solenoid and the one towards the fire wall on the passenger wheel well cycle when the engine runns crappy. I removed the vacuum line from the bottom of the MAP sensor and the engine ran perfectly (w/ exception of solenoid going nuts). So now off to replace the MAP sensor. So far the EGR and position sensor were $127 total, the map sensor is $60. So lets see what that gets me.

[Sparkman337]

Replaced the MAP sensor and ran some Sea foam through the vacuum lines. Truck runs fine now, but that also happened when I replaced the EGR and Position sensor. So lets see how long this will last? I will keep you all posted.

[Sparkman337]

Well this lasted all of 16 hours. I replaced the MAP on monday evening about 7pm, ran the truck for 30 min and drove it around. Ran fine with no issues. Drove it to work tuesday morning also with no issues. Went to lunch at 11 and it it back to running like crap. It is still sputtering at idle but runs when give gas. I have replaced MAR, EGR valve (w/gasket), and EGR Position Sensor. Not sure what else to replace or check. I am going to dump an entire bottle of seafoam into the vacuum system and see what happens. Will also have timing and carb tune checked. not sure where else to go. Help Please!