Cam sensor signal missing

Holden/Delco Tuning. ALDL, OBD 1.5. Circa 1989 to 2004.
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Cam sensor signal missing

Postby wrx884 » Thu Dec 24, 2020 4:42 pm

Hey Guys im trying to track down an issue with my 98 VT L67 where now im at a point its not driving but is cranking over but not firing.

Original issue was i started getting bad hesitations while driving mainly under load so i did all the basics 1st, so far replaced/testing with known parts from an NA ecotec motor. coil packs, DFI, leads, TPS, IAC, fuel filter (new), CAS (new non genuine), cam sensor etc... but to no avail. checked all connections and cleaned most even tho all looked good. started changing vac lines as i noticed some of those rubber elbow pieces were getting stress cracks in them. Can hear the fuel pump prime when u turn the key so as far as i know thats all good.

Recently had a tech 2 unit hooked up to see what was happening and so far we were getting no codes logged but the tech 2 said the cam signal was missing, sometimes it would be there but even then the car wont run. where should i start to start looking into this signal that's missing or intermittent? another thing we noticed that was odd while the tech 2 was running some checks i could hear a solenoid clicking from the gear box area sometimes but not all the time so not sure if this is something that's causing the issue?

Some more back round info the body of this VT is from an NA ecotec and i had another VT L67 as the donor car that was my daily driver that didnt have any issues prior. The motor, gearbox and fuel tank from the L67 body was all swapped over as was the PCM, BCM and fob key. After the motor and drive line swap the car run perfect for a month with no issues so im kinda certain anything we did there should be fine?

any help much appreciated cheers.

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Re: Cam sensor signal missing

Postby 'quipt4it » Thu Dec 24, 2020 5:58 pm

Hi wrx884,
Running OK then running slightly off then nothing at all points to one of those sensors.
CAS have been problematic for these since they were new. I wouldn't trust 'off brands', especially with even genuine items having problems.
Intermittents are the hardest to track (fwiw).
Did it run after you replaced the CAS?
If not, you may have inadvertently 'wiped' it without properly 'gapping' it in the interrupter rings.

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Re: Cam sensor signal missing

Postby 'quipt4it » Thu Dec 24, 2020 6:28 pm

Just confirm, running OK> running bad> replace with those parts> not running.

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Re: Cam sensor signal missing

Postby vlad01 » Thu Dec 24, 2020 6:29 pm

There is no gapping on the VP series 2 onward CAS, they are not adjustable and have a very large gaps for plenty of leeway. I do agree, I head a lot of the non genuine CAS die very quick, never had an issue with genuine though. All of mine have lived longer than the cars they're in.
I'm the director of VSH (Vlad's Spec Holden), because HSV were doing it ass about.

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Re: Cam sensor signal missing

Postby 'quipt4it » Thu Dec 24, 2020 6:31 pm

vlad01 wrote:There is no gapping on the VP series 2 onward CAS, they are not adjustable and have a very large gaps for plenty of leeway. I do agree, I head a lot of the non genuine CAS die very quick, never had an issue with genuine though. All of mine have lived longer than the cars they're in.

You had better luck than me :lol:

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Re: Cam sensor signal missing

Postby vlad01 » Thu Dec 24, 2020 6:34 pm

Only time I ever had an issue was with the early type with the small gaps and a powerbond balancer having too small gaps to even work with the sensor, chewed it out. Got a genuine used balancer and a 380K old used CAS, 120K later still going.
I'm the director of VSH (Vlad's Spec Holden), because HSV were doing it ass about.

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Re: Cam sensor signal missing

Postby 'quipt4it » Thu Dec 24, 2020 6:35 pm

vlad01 wrote:Only time I ever had an issue was with the early type with the small gaps and a powerbond balancer having too small gaps to even work with the sensor, chewed it out. Got a genuine used balancer and a 380K old used CAS, 120K later still going.

I'm sure I saw you touch wood there
Last edited by 'quipt4it on Thu Dec 24, 2020 6:38 pm, edited 1 time in total.

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Re: Cam sensor signal missing

Postby vlad01 » Thu Dec 24, 2020 6:38 pm

I guess I was already, desk is wood afterall.
I'm the director of VSH (Vlad's Spec Holden), because HSV were doing it ass about.

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Re: Cam sensor signal missing

Postby 'quipt4it » Thu Dec 24, 2020 6:39 pm

vlad01 wrote:I guess I was already, desk is wood afterall.

lol

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Re: Cam sensor signal missing

Postby vlad01 » Thu Dec 24, 2020 6:48 pm

My last car I did over 400k on the engine, if you take an average of 60km/h and 2500rpm thats 1 billion revs, or about 18 billion cycles of the sensor itself. Pretty reliable if you ask me.

Not sure now if that was the same CAS i used on my daily or the VN one I had from 384K but either way done another 120k on top. I got a spare in case.



Anyway I would check the connector pins and wires at the DFI plug, cam sensor runs to there but it should run fine without the cam sensor. So if everything has been replaced I would check that. Fuel and spark is all you need to get running, so start with checking spark.
I'm the director of VSH (Vlad's Spec Holden), because HSV were doing it ass about.

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