Loss of power, idles under throttling

Craig Almaguer

Well-known member
As some of you may know, I replaced the injection pump and timing belt, all the push rods and some rocker arms, and all the copper washers on injectors and banjo bolts at injectors. I put it all back together and it started! I drove around town on several occasions yesterday. It did well around town and on the freeway at 65mph, two separate occasions. On the way home yesterday, from work, I suddenly experienced a loss in power. I barely made it home in second gear, and had to throttle the gas pedal and keep it pegged to the floor most of the time. RPMs were very very low…Super sluggish and zero pep. Upon entering the driveway and coming to a stop, I sat there and let it idle, and tried to rev it a little bit before turning it off. I did also hear very faint, whining noise, right before the turbo kicked in, and drowning that whining noise. Could I have tightened my timing belt a bit too tight? slipped a tooth? Wondering if the whining noise came.

Do I find top dead center on the flywheel and then make sure the pin slips into the injection pump? But is it possible the cam pulley slipped? While fitting the belt, I did notice the injection pump pulley and the cam pulley are ever so slightly off. Like half a tooth when I rotate the crankshaft, the belt slipped in but when I reached 180° on the crank pulley the belt would lift a little bit exposing half a tooth “off” … until I tightened the tension pulley. I suppose I need to take everything apart and expose it all to see if the injection pump pin fits. The crank pulley is straight up at 12 o’clock and the cam pulley lines up with the little dot and crease mark?

I feel that sudden loss in power maybe was the belt/tooth slipping. Now, is it possible my pushrods are jacked up now? OMG, this is killing me.

Thanks for your support



Well-known member
I know it sounds stupid, but in the past I've had the accel cable come loose and experienced the same symptoms(besides the whining).

I would inspect the cable while someone inside the car pushes the accel pedal down&up a few times


Well-known member
I’d pull the timing cover and inspect the timing. You should have a timing mark for the pump, crank, and cam cast into the timing case. Those, along with aligning the flywheel timing pin, should make it clear where everything should line up.

On the crank pulley I’d make sure you have the solid type, not the type where the sides are spot welded on. Those fail catastrophically.

Ideally, you would have pulled the head to inspect for valve/piston damage, but I understand the hesitancy.


Well-known member
Check your air cleaner element and that it's not soaked with oil.

Open prime port on fuel filter housing and hand prime, should have zero air and immediately push fuel out, so be ready.

If you crack open the timing case for inspection, get a paint pen and mark all your targets. spin engine a few times by hand to make sure its correct. take a photo for future review.

Craig Almaguer

Well-known member
Thanks, you guys for the tips. I did pull the timing cover and inspected. All seemed OK, but the fuel injection pump seemed slightly off ….reset timing on bottom, flywheel, crank pulley, cam pulley, and adjusted the injection pump slightly - I honestly don’t know if it was out, but obviously something was off. It all went back together, well, and fired it up, and it’s been running fine. I ran a few errands right now, filled up a full tank, and even added some Diesel Kleen injector cleaner. Very little black smoke and seems to pur like a 300 TDI should. lol

Thanks again!!