Hello all im new to the forum. i have a 1988 d100 with 318 tbi when i got it it did not run it seemed to be a timing issue i have pulled it up to tdc and put it back in time changed the hall effect,cap,rotor,and wires and now it only runs at wot and like its on 4 cyl. then. i dont know what to check next. any ideas? i am building a 400+ 4barrel engine for it but need it to run now, any help would be great. thanks

 

You have made sure the firing order is correct and none of the wires are crossed, right?
I had that problem when I replaced the wires on my 76, the wiring diagram was backwords and the truck wouldn't start.

 

when you set the timing did you follow the correct procedure?

At operating temp with the coolant temp sensor disconnected?

 

I don't have that issue, my problem was the diagram in the Haynes had everything on the dizzy backwords, so I had to re-route the plug wires in the opposite side of the dizzy cap.

Try to find a procedure for setting the timing

 

As far as the firing order I've checked and double checked. I know to get it exactly right I've gotta run it up to temp with the coolant temp sensor unhooked. But I can't keep it goin long enough to get it to temp. Thank you guys for responding so fast this thing is drivin me nuts! I've built and owned ten or more of these trucks but this is my first tbi

 

have you pulled the spark plugs to see what they look like?

 

I did they looked great I probably should've spent the extra 20 buck and just bought a set but they look to have very few miles on em and no gas fouled smell on any

 

First; did you remove the distributor?

Bring the engine to TDC with the #1 cylinder in firing position and make sure that the rotor is pointing at the #1 wire on the cap. I have seen people change wires and get the firing order correct but they started the #1 wire on the wrong terminal of the cap.

 

Is it possible that you re-installed the dizzy 180 degrees off? From the top, the cap and wires would look correct, and by all other accounts, is correct. But the shaft and thus, the rotor are exacly backwords. Not to tell on myself, but Ive done it. Pretty easy to do really, and as soon as I turned the key, I knew what I did wrong.

 

I took out the dizzy found tdc and then put it back in the rotor looked to be pointed dead at one but I've been wrong before I plan on pulling it back out and doin it all over again just to be sure and to check the firing order again... When I bought the truck all it would do is turn over once I finally got it home to work on it the previous owner had the distributor loose and had done a "tune up" gotta love cleanin up other peoples messes right thanks again you guys