Jump to content
SAU Community

Recommended Posts

Ok here is an update to the matter in case its useful to anyone.

I went to another sau member place (500hp) and after some testing he isolated the likely culprit is the AIR flow meter. With the air flow meter unplugged, the car held 15 btdc timing fine. Unplugging the other sensor, TPS, aac vavle, etc did nothing to to affect the irrational timing. Plug the AFM back in, car shuts of, upon restart the timing is jumping around again.

So I will try get another AFM and see if that fixes the issue. Hopefully it fixes the 02 sensor being all over the place too.

It's not the cam gear that is worn out, the cas doesn't connect to the cam gear at all. It passes straight through the middle of it and into the camshaft. It's possibly the drive in the camshaft that is flogged out, not anything to do with the cam gear. Can happen when people don't fit the CAS properly, eg. not putting the spacers in between the CAS and the mount, causing the CAS to sit further in than it should and damaging things.

Ok I understand exactly what you mean now. I had a look at the drive on both camshaft and cas end and they a are both fine. A half moon piece of metal shaking hands with the opposite other.

Ok , why do you think you actually have a problem? The ecu alters the timing to maintain idle. Unplug the tps and see what happens. Thats what you have to do when timing the car. How did you set tge base timing when you swapped the cas?

I think I have a problem because the timing should not be jumping around like crazy at idle. I have tested other cars and they hold steady timing fine at idle and above. Unplugging the TPS doesn't change it. I am now definitely satisfied mine is abnormal.

Your best off giving it to someone to look at for you who knows what causes the issues your having.

30mins and the problem should be located.
5mins pulling the CAS out and physically looking at the drive peg
15mins putting a scope on the two signal wires
5 mins checking the shielding
And 5 mins of fart arsing around tidying up.

It might take more than 30mins to fix the problem but locating it is not hard.

I've got several Sensors at the workshop your welcome to try them but chances are it won't be the problem.

I really appreciate that. I just managed to try another members cas and it was still jumping around, but in his car minutes ago the same cas wasn't. So yes you are correct it isnt the cas. As above it seems the AFM is the culprit.

Edited by sonicz

use datascan to set base idle, if it still does it while its in the "set mode" its abnormal....

i see that timing fluctuation on a daily basis at idle... not abnormal just a few things new adjusting.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Latest Posts

    • Nah, I think the current user name suits me pretty well
    • Ooo, quite aggressive! I hope there'll be a professional taking photos on the trackday that you can get. Should look great there!
    • I think a lot of you hit the real issue, these brands aren't making cars at a competitive price. Lucky that Foxxconnnn didn't buy Nissan otherwise the cars would be built by 13 year olds doing 15 hour shifts like iPhones. This reminds me of British Leyland. 5th largest global manufacturer in 1968, collapsed by 1975 with only a couple of brands escaping to be owned by Chinese brands today. Along they way they vacuumed up MG, Jaguar, Daimler, Rover, Land Rover, Austin, Morris, Wolseley, Mini, Triumph, Riley, Alvis,  Yes, they had other problems but the basic issue was the wrong production (and therefore retail) price. If you are a car manufacturer and you haven't noticed China coming, its already too late.
    • Or the cistransgender
    • I can't help with the clearance question, I've always taken my machine shop's advice on that. It is worth considering that a shop that does that every day for road cars will be looking for as good as they can get off the shelf, not perfect. If you want more careful race style "blueprinting" then you need a race shop to measure/machine the engine. I do have an opinion on line boring the block though....don't do it unless you have to. The crank centre moves higher but the oil pump stays in the same place when you line bore the block.
×
×
  • Create New...