What can cause P0016, the check eng. Lite stays on and if cleared comes right back on

ROJOMAN

MEMBER
2003 DODGE CARAVAN
73,300 MILES

The van has no power under load, surges and stumbles at times. You can drive it up to 45-50 mph if you very gently accelerate, above that it starts to fall flat or if you jump on the accelerator it will stumble and hesitate. The vacuum reading is low 11.5-12in with a fluctuating gauge but it will smoothe out some around the midpoint of the rpm range, the compression is 160 psi plus on all 4 cyl. It has a new cam and crankshft sensor the timing marks all line up it acts like the convertor is plugged but its not, the pcm has the software update sticker on it, fuel pump psi is 60 plus at idle. I am leaning towards the crankshft tone wheel is that possible and replaceable.

1 Reply

JACOBANDNICKOLAS

MECHANIC
109,885 POSTS

This code leads to the crankshaft and camshaft position sensors. Here are some possible causes for this code:

Timing chain stretched, or timing belt skipped a tooth due to wear, misalignment of timing belt/chain, tone ring on crankshaft slipped/broken, tone ring on camshaft slipped/broken, bad crank sensor, bad cam sensor, damaged wiring to crank/cam sensor, or timing belt/chain tensioner damaged

Check both crank and cam sensors for damage. Also, check for wiring issues at both points. Remove the crankshaft harmonic balancer and check the tone ring to make sure it is tight and not damaged as well as making sure the shear key hasn't been damaged causing a misalignmeent. If everything checks good, then you will need to check the timing belt to see if it is stretched or the tensionier is allowing excessive play. Regardless, the problem is due to the crank and cam sensors not working together. That is causing the power loss.