Thread: 300 tdi problem

Check the wiring to the fuel stop solenoid at the back of the injection pump. It is simple push fitting and if loose/cracked/dirty can intermittantly affect the stop solenoid. With the key turned to IGN you will hear the solenoid click as you fit/remove the wiring.

Next step would be possibility of water or gunge in fuel, drain or remove the fuel sedimentor bowl at the drivers side, inside chassis rail back near the fuel tank. And obviously the main fuel filter too. You say glass bowl so I assume it is a RACOR et al replacement. Ive found in marine settings the water level can be high wnough that you dont notice water/fuel level in the bottom of the bowl... drain it and check.

Not much else will make a 300tdi "misfire" intermittantly, if the timing is out it will be always rough, if an injector is sticking youd presume it would always be rough.

S

Ditto what roverrescue said.
The solenoid connection has required a periodic clean up on mine thanks to corrosion on the spade.

Often shows up as a miss while running, or just wont start even though had been running fine prior to shut down.
Clean the terminal and away it goes.

Might be worth while taking the rocker cover off & checking for bent push rods & timing. Dosn't take long, might save a few dollars. My tensioner went but didn't give the normal tell tail signs.
Cheers Mick.

Make sure the connector ''clicks'' when fitting it.Mine played up for ages because the spade was between the connector and insulation. Pat

thanks all. tried the connection filthy wiped it off a bit and all seems fine.

It's stuff like this that makes me love this forum...

Originally Posted by trog

thanks all. tried the connection filthy wiped it off a bit and all seems fine.

I use a bit of Scotchbrite and clean it off with contact cleaner.

Heres another one concerning the fuel shut off solenoid.

I hope this helps someone, because I am not likely to see anything like this again, thank goodness. It took a while to find and rectify.


The symptoms were 300Tdi manual D1, driven hard, it would jerk, like the key being quickly turned on and off. Fuel solenoid thought I. Checked it, it clicks, it shuts off and turns on, can't fault it. Engine NEVER stopped completely, just violently jerks when pushed hard, even worse when cold.
Check wiring harness for problems, IE wiggle tested every inch all the way to the ignition switch, still nothing. I even ran a straight 12 volt jumper wire from the battery and it STILL did it.
Couldn't duplicate it AT ALL unless driving.
So, I removed the fuel solenoid and inspected it. All OK, or so it seemed...
Gasses and fluids can induce a sideways pressure, called bernoullis principle, where a fast moving fluid or gas can cause a negative sideways pressure, like how a spray gun works. When demanding more fuel flow, the coil in the stop solenoid was too weak to hold the plunger against the combined spring pressure and fuel flow rate, sucking it closed and momentarily shutting off fuel flow. As soon as the flow stops, the valve pops open again and so on.
I replaced the tested 'OK' solenoid, and all is now OK.


Made the brain cells work a bit that one.

JC