1997 5.7 4l60e bad highway miss and huge clunk. MAF reads 0

[94Sierra4x4]

My truck has an insane clunk/shudder/shake in overdrive anywhere from 1100-2000 rpm.
Just scanned my truck, MAF and camshaft position sensor.
Cleared codes, MAF popped up right away. Nothing else.
Reads 0.00 g/s at all throttle positons.

Obviously going to check the connections but its been doing this a while. Mostly not driving highway but
Normal everyday driving I have a bad miss.

Any input?
Also cam retard is -45° ...is this normal? Or being caused by bad reading from MAF?

Thanks guys!

Also, is Delphi a good brand for a replacement? $110 compared to ACDelco at $290 on rockauto

 

[94Sierra4x4]

Replaced the MAF. Still reading nothing. No power going to it (should have tested that first...hind sight)
So. Broken wire is obviously on my mind.
Is it possible the computer is the problem?
Going to try and get a hold of one to swap in and try it.
Any input would be great.
Cheers

 

[98_k1500]

Cam retard needs to be 0°. Mine stayed on -45 when i had a bent pin on my cam sensor. If its completly bad/unplugged, you the the -45 setting and it runs like poo. Need to look into this problem, may be easier to fix than the MAF and will narrow it down to only one problem.

 

[Carlos S]

Again cam retard needs to be 0 or close to. Mine was at -9 and at 2000 rpm overdrive i had a random misfire and bad mpg. Got the cam retard to 0 and truck was back to normal.(1997 two door tahoe 5.7) if i was you i would try to set at 0 before putting more parts on.

 

[94Sierra4x4]

How do I set the cam retard to 0? Or do I just replace the cam position sensor?
Thanks guys for the input. Seriously appreciate it.

 

[98_k1500]

Depending on what it costs, i would replace the cam sensor. You adjust the cam retard by turning the distributor, same method older engines use to set the ignition timing. May want to check the wiring good since you have known wiring problems. I would not move the distributor until i replaced the sensor tho. It can be changed without removing the distributor if the engine is turned to the right spot.

 

[94Sierra4x4]

So if I can't remove the sensor. Just give the key a crank till it's in the right spot?
I'll be checking wiring after I try a different computer, hopefully soon.

 

[94Sierra4x4]

Tested MAF ground, key on engine running, B+ to blk/wht wire, test light is lit. Ground is good...
Tested MAF power, B- to pink, no light, tested it just before it enters main harness then into pass side firewall.

 

[94Sierra4x4]

Tested MAF ground, key on engine running, B+ to blk/wht wire, test light is lit. Ground is good...
Tested MAF power, B- to pink, no light, tested it just before it enters main harness then into pass side firewall.

Edit: tablet didn't refresh thought I hadn't posted sorry.

 

[94Sierra4x4]

WOW..... The previous owner had removed the ENG-1 fuse..... Quickly reset codes, robbed the 20a horn fuse and plugged it in place. No code. Quick test drive revealed, way more power, and NO missfire, shake, clunk in overdrive, or at all....... My goodness.

Thank you guys for your help.
I am in 7th freaking heaven right now. Such a simple fix, wow.

Atleast she needed the new set of plugs and that old MAF was diiiirty, money well spent all things considering!
Thanks again.