Help Detoit series won't start-gives Code 21

Look at the simplest thing first- is the fuel transfer pump working? The gears in it are often plastic- they crack and crumble when they get old.

Is your electrical system letting you down? Bad battery, or shorted battery, corroded grounds- is the ecm wire corroded where it's mounted on the positive terminal on the battery? Are the connections on the ecm loose, or corroded? Is the fuse for the ecm blown out?

Is the drain valve open on the water separator? If this is the first startup after the rebuild, are the fuel lines connected backwards on the transfer pump?

Good luck- hope it's an easy fix.

 

the connectors on both of these sensors tend to corrode because of the heat and little air flow where they are mounted.look at them closely.they may look fine,but break where they enter the plastic connector.give each wire a hard tug.you can by replacement connectors with 6 inch wire at napa.tell the counter person to look in the echlin catalog.good luck.

 

Use WD-40 instead of either. The engine will start fine with it, but you won't get the explosion you get with either, and the lubricant in the WD-40 will keep the cylinders lubricated. You can run the engine as long as you like with this. I have used a full large can all at one time trying to get fuel picked up with no problem before.

 

If it runs on ether it either is not getting fuel or the ECM is not letting it fire. I tend to lean toward the latter.

 

If it doesnt smoke at all and has good fuel pressure then its an electrical issue. Could be a pinched wire, unplugged sensor, cam sensor not picking up correct signal, weak batteries that are dropping voltage too low to power ecm usualy around 9 volts or ase simple as a blown fuse

 

Code 21 is Throttle Sensor Voltage High.
Code 52 is ECM A/D conversion fault.
Code 51 is not a valid flash code. Suggest recheck this.

"Dash is flashing engine shutdown and gives code 21 as reason." Do you mean that the red Stop Engine Light(SEL) is flashing this code when you press the diagnostic switch? This only means that the fault is active. Code 21 is NOT a shutdown fault. It will only bring on the orange Check Engine Light(CEL), and the throttle wont work(engine wont rev up).
Is the SEL on when you try to start the engine?

Timing sensor codes are 41(missing TRS) and 42(missing SRS).

S60's can be a pain to bleed. Suggest you try pressure bleeding into the secondary filter while cranking. Get one of those cheap pump up plastic garden sprayers and replace the spray wand with a 1/4NPT fitting.