I have an 89 TII and I recently removed all the emissions. It'll turn over and fire up but won't stay going unless I hold down the throttle. As soon as I let go it dies.

It's throwing codes:
9 - Water Thermosensor Engine
11 - Air Thermosensor Engine
12/18 - TPS

Now, I know the TPS and water thermosensor are good because I just replaced both of them the other week. I wouldn't imagine how the air thermosensor would go bad so I'm led to believe it's something electrical. Does anyone know if all three have a common ground? I had to remove both of the grounds when I did the rats nest removal.
I hope it's just something as simple as running new grounds.

 

you removed the grounds? im thinking you need those grounds..... because all those sensors are on the same sub-harness.

 

No, I removed the grounds to get the brackets out of the way so I could remove the rat's nest. I put them back after I removed everything else of course. So, the grounds are there and connected. I think I'll just run some new wire and reground everything to somewhere else and see what happens.

 

You just go to the FSM. You look in the fuel section. You find a section called CONTROL UNIT. It shows what the input/output of each pin on the ECU plugs should be. You backprobe each wire that relates to the componets you mentioned and compare your reading with that in CONTROL UNIT. You make corrections based on what you saw.

All three of those sensors have their ground wire in common with each other. Their gnds are all spliced together and return to a pin on the ECU. Other sensor gnds are also spliced to the ones mentioned. Like the afm's gnd, the boost sensors gnd etc. They ALL gnd THROUGH the ECU. The ECU has it's grounds on the engine. On a series four those two ECU gnd wires are on the rear rotor. On a series five I think that ECU gnd is in another place. See your local series five FSM for the location.