cam sensor malfunction

[bigstick83]

i have that on my dtc's and a maf sensor or a vaf circuit low input, ok heres what happend i had a new engine put in and this dumb a$$ didnt run my maf sensor wires in a very good place and they melted through to the bare wires on my manifold and i fixed the wires but the light is still on and i cleared the codes and the ight come one right away after i start it.............................. any other ideas????????

[Sparky2263]

Need some punctuation inserted there. Having a hard time clearly understanding what you're saying.

Also, what code numbers, specifically, are you retreiving from the computer.

If it is the MAF wires that melted, it may have fried the MAF sensor if the 12V wire contacted the reference or return wires. No biggie to start as you can run w/o the MAF sensor. BUT, first things first.

[bigstick83]

sorry bout ths spellin i was in a hurry. i edited it so its better. i put a maf off an ls1 on it and it still dont work, i was told i could use one of them but i was pry told wrong

[Sparky2263]

i the ight come one right away after i start it.............................. any other ideas????????

What code is it setting? The code number, please.

[bigstick83]

p0102 and a p0340

[bigstick83]

would that have possibly burned up my cam sensor?

[Sparky2263]

P0102 indicates the MAF is reading nothing. Very easy circuit to diagnose. 12V on the pink wire from the 20A Eng. fuse, ground is the black w/yellow stripe wire and yellow is signal return. Here's the description and operation straight from the general;

Circuit Description
The Mass Air Flow (MAF) sensor measures the amount of air entering the engine during a given time. The VCM (http://motoralldata.com/alldata/MOTOR~V36017007~C26393~R0~OD~N/0/41746678/42420944/42420959/42420960/34853741/34857029/34857030/34857300) uses the Mass Air Flow information for fuel delivery calculations. A large quantity of air entering the engine indicates an acceleration or high load situation, while a small quantity of air indicates deceleration or idle.

The MAF sensor produces a frequency signal which can be monitored using a scan tool. The frequency varies within a range of around 5 to 7 g/s at idle to near 125 g/s at maximum engine load. This DTC sets if the signal from the MAF (http://motoralldata.com/alldata/MOTOR~V36017007~C26393~R0~OD~N/0/41746678/42420944/42420959/42420960/34853741/34857029/34857030/56191599) senor measures below the possible range of a normally operating MAF sensor. This DTC is a type A DTC.

Conditions for Setting the DTC Low Frequency Test



The engine is running.
Engine run time is greater than 0.4 seconds.
System voltage is at least 8.0 volts.
The above conditions are present for a period of time greater than 0.0 seconds
Action Taken When the DTC Sets




The VCM (http://motoralldata.com/alldata/MOTOR~V36017007~C26393~R0~OD~N/0/41746678/42420944/42420959/42420960/34853741/34857029/34857030/34857300) illuminates the Malfunction Indicator Lamp (http://motoralldata.com/alldata/MOTOR~V36017007~C26393~R0~OD~N/0/41746678/42420944/42420959/42420960/34853741/34857029/34857030/56492543) (MIL) the first time the fault is detected.
The VCM (http://motoralldata.com/alldata/MOTOR~V36017007~C26393~R0~OD~N/0/41746678/42420944/42420959/42420960/34853741/34857029/34857030/34857300) calculates an airflow value based on Idle Air Control (IAC) valve (http://motoralldata.com/alldata/MOTOR~V36017007~C26393~R0~OD~N/0/41746678/42420944/42420959/42420960/34853741/34857029/34857030/56492533) position, throttle position, engine speed and barometric pressure.
The VCM (http://motoralldata.com/alldata/MOTOR~V36017007~C26393~R0~OD~N/0/41746678/42420944/42420959/42420960/34853741/34857029/34857030/34857300) stores the conditions which were present when the DTC set as Freeze Frame and the Fail Records data.
Conditions for Clearing the MIL (http://motoralldata.com/alldata/MOTOR~V36017007~C26393~R0~OD~N/0/41746678/42420944/42420959/42420960/34853741/34857029/34857030/56492543)/DTC




The VCM (http://motoralldata.com/alldata/MOTOR~V36017007~C26393~R0~OD~N/0/41746678/42420944/42420959/42420960/34853741/34857029/34857030/34857300) turns the MIL (http://motoralldata.com/alldata/MOTOR~V36017007~C26393~R0~OD~N/0/41746678/42420944/42420959/42420960/34853741/34857029/34857030/56492543) off on the third consecutive trip cycle during which the diagnostic has been run and the fault condition is no longer present.
A history DTC clears after 40 consecutive warm-up cycles have occurred without a fault.
Using the scan tool Clear Info function or disconnecting the VCM (http://motoralldata.com/alldata/MOTOR~V36017007~C26393~R0~OD~N/0/41746678/42420944/42420959/42420960/34853741/34857029/34857030/34857300) battery feed clears the DTC.
Diagnostic Aids
Check for the following conditions:




A poor connection at the VCM (http://motoralldata.com/alldata/MOTOR~V36017007~C26393~R0~OD~N/0/41746678/42420944/42420959/42420960/34853741/34857029/34857030/34857300). Inspect harness connectors for the following conditions:
Backed out terminals
Improper mating
Broken locks
Improperly formed or damaged terminals
Poor terminal to wire connection
A misrouted harness. Inspect the MAF sensor harness in order to ensure that it is not routed too close to high voltage wires such as spark plug (http://motoralldata.com/alldata/MOTOR~V36017007~C26393~R0~OD~N/0/41746678/42420944/42420959/42420960/34853741/34857029/34859584/58828691) leads.
A damaged harness. Inspect the wiring harness for damage. If the harness appears to be OK, observe the scan tool while moving the connectors and the wiring harnesses related to the MAF sensor. A change in the display indicates the location of the fault.
A plugged intake air duct or filter element. A wide open throttle acceleration from a stop should cause the Mass Air Flow displayed on a scan tool to increase from about 4-7 gm/s at idle to 100 gm/s or greater at the time of the 1-2 shift. If not, check for a restriction.

[bigstick83]

um... my scan tool dont read that detailed

[Sparky2263]

Just make sure you have 12V and a good ground. If you have that, then you should see a small voltage on the return wire. If not, I would disconnect my return wire at the MAF and ck. voltage again to make sure the return wire isn't grounded somewhere.

[bigstick83]

Just make sure you have 12V and a good ground. If you have that, then you should see a small voltage on the return wire. If not, I would disconnect my return wire at the MAF and ck. voltage again to make sure the return wire isn't grounded somewhere.



i'm only gettin 5 volts from those pink wire and yellow wires

[Sparky2263]

Then the wires are hooked up wrong. The 5 volts is a reference voltage from the VCM. You need to trace back your wires and ensure you have 12V on the pink and a good ground on the blk/wht wire.

[bigstick83]

Then the wires are hooked up wrong. The 5 volts is a reference voltage from the VCM. You need to trace back your wires and ensure you have 12V on the pink and a good ground on the blk/wht wire.


if i cant get 12 v out of it can i run a 12v hot wire to it or not?

[Sparky2263]

if i cant get 12 v out of it can i run a 12v hot wire to it or not?

Yes, you can, but that's NOT the right way to do it. If you do, DO NOT splice it in, run it independent of other wires. You still need to make sure the signal wire from the VCM is intact with good integrity.

[rat]

I said this on annother forum, but. The ecm B fuse i think it is called runs the camshaft position sensor, maf, and evap stuff.

[Sparky2263]

I said this on annother forum, but. The ecm B fuse i think it is called runs the camshaft position sensor, maf, and evap stuff.

His wiring burned on the exhaust. It needs to be wired properly and integrity assured.

[bigstick83]

wheres that fuse at

[bigstick83]

nevermind thanks for all the help guys i gotrdun

[Sparky2263]

nevermind thanks for all the help guys i gotrdun

What ended up being the problem/solution ?

[bigstick83]

What ended up being the problem/solution ?


when the wire grounded out it popped the fuse, so i taped it all back off and put a new fuse in and its all good now, i didnt know there was a fuse for that is y i had the most trouble