wont rev past 3k Rpm

mjbrox

Well-known member
Jun 30, 2008
1,812
48
Golden CO
I finially got around to pulling what I thought was the Camshaft sensor but turned out it was the crankshaft. While the insulation on wires where intact, they where super brittle. I am going to replace the pigtail and hope that helps. If not, I guess I should replace the Camshaft sensor.
 

mjbrox

Well-known member
Jun 30, 2008
1,812
48
Golden CO
I replaced the pigtail and now it will rev to 4000 RPMS before it stops.

oh well, thats enough to go wheeling this weekend
 

joneschris

Well-known member
Aug 25, 2019
167
32
The Woodlands, TX
I finially got around to pulling what I thought was the Camshaft sensor but turned out it was the crankshaft. While the insulation on wires where intact, they where super brittle. I am going to replace the pigtail and hope that helps. If not, I guess I should replace the Camshaft sensor.

Just a fyi - the crankshaft position sensor is the same pigtail as a d1 foglight
 

mjbrox

Well-known member
Jun 30, 2008
1,812
48
Golden CO
Okay, im still having this problem. Things i have tried/checked

Cats dont rattle
Changed Crankshaft pigtail,
Switched to known good MAFs
Ran Truck with Temp Sensor unplugged
Ran Truck with o2 sensors unplugged
Verified i had good fuel pressure

One thing that PT said was peculiar was that my MAF never gets above 0.07 lb/min. But the readings seem to be independent of truck temp.

Thing is that this is temperature dependent but seems to be more time driven dependent. For example, the rev limit decreases as I drive it over time. But one test drive it would limit at 4k and the ECT was 185, then on a really cool day i drove it for 20+ mins and couldn't rev past 3k.

I do have a used camshaft position sensor but from what I understand that would just create a poor start condition. The truck starts/runs great when cold.

On Wed i am going to borrow a Foxwell NT530 scanner but honestly i dont know what to do with it.
 

mjbrox

Well-known member
Jun 30, 2008
1,812
48
Golden CO
I changed the camshaft position sensor with a used one and now it cranks but wont start........

This is so damn frustrating