Why is my CAS maxed out?

[DJ23GSX]

I recently replaced my alternator and upgraded my turbo (20g) and after putting it back together the car ran like crap and knocked all over the place. I checked base timing and for some unknown reason it moved from 5* to 10* after putting on the new alternator and turbo. As it sits right now my cas is maxed out just to get base timing down to 5*. Before the alternator died the cas was just about dead in the middle to get the base timing to 5*. I'm trying to tune the 20g at around 20psi with an safc and I think my timing is too aggressive and causing knock so I would like to try and lower the base timing a bit. Is my cas bad or should I be looking elsewhere for a problem? My buddy has a 1ga (might even be a 90) cas kicking around but my car is a 1gb are they interchangable? Please don't suggest ecm link to fix my knock/timing issue. I would love to have it but I can't afford it and I got the safc for next to nothing. I've never had issues tuning out knock with the safc before this cas/base timing problem started. Oh and one more thing the car runs 93 octane 24/7.

Thanks

 

[EMX5636]

What size injectors are you trying to control with that SAFC?

For your problems, it could be a bad CAS, but they usually won't give consistent readings, or at any at all if it's bad. If your buddy has a 91-94, you can swap it for testing. 90's don't have the same wiring.

Another thing that it could be, is the intake cam is off a tooth, but I doubt it. Just pull the upper timing cover just to eliminate the possibility.

Once you get your CAS figured out, try running a bit less base timing if you can't spring for Link. Probably 2-3* base will help out a bit up top.

 

[TurboLaserRS]

I would say something is certainly suspect with your CAS. That is odd that it is maxed out like that. Mine is right in the middle like you said, so maybe your alternator fried the CAS. If you removed it, did you make sure it's not 180 out? Some have said it's not possible to run it that way, but mine runs, just at a very low idle.

 

[DJ23GSX]

What size injectors are you trying to control with that SAFC?

For your problems, it could be a bad CAS, but they usually won't give consistent readings, or at any at all if it's bad. If your buddy has a 91-94, you can swap it for testing. 90's don't have the same wiring.

Another thing that it could be, is the intake cam is off a tooth, but I doubt it. Just pull the upper timing cover just to eliminate the possibility.

Once you get your CAS figured out, try running a bit less base timing if you can't spring for Link. Probably 2-3* base will help out a bit up top.

I'm currently running 680's with a custom dsmchip eprom to compensate for them. I've checked the marks on the cam gears before and they were perfect. It's funny you say 2-3* base timing will help up top cause that's exactly where the car needs lots of fuel to get rid of knock and kinda falls on its face. I've seen timing up over 20* over 5k rpms on logs before hence the need for more fuel. I was running 19psi on the 14b before and the car pulled right to redline so I'm kinda confused why a bigger turbo would fall off in the upper rpm's like I'm experiencing. I'm guessing that the timing is too aggressive up top for the amount of air I'm flowing now with the 20g and I'm probly running really rich up top to compensate and making it feel like its falling off. Unfortunately a wideband is on the to do list right next the link.

I would say something is certainly suspect with your CAS. That is odd that it is maxed out like that. Mine is right in the middle like you said, so maybe your alternator fried the CAS. If you removed it, did you make sure it's not 180 out? Some have said it's not possible to run it that way, but mine runs, just at a very low idle.

The CAS has never been off the car so I would assume its not 180* off. I had no problems at all before the alternator setting base timing.

 

[EMX5636]

Are you grounding the timing connector while checking? Not insulting you, just making sure.

As far as the knock goes, my car gets a lot of rich knock so you might be going too far with adding fuel. Without a wideband though, it's only a guess. Any mods to the MAF?

 

[DJ23GSX]

Are you grounding the timing connector while checking? Not insulting you, just making sure.

As far as the knock goes, my car gets a lot of rich knock so you might be going too far with adding fuel. Without a wideband though, it's only a guess. Any mods to the MAF?

yes I'm grounding the timing connector and unhook the datalogger to adjust the timing. I'm running a completely stock 2g maf that still has the goo on the adjustment screw and all the honeycombs are still intact. I don't think its rich knock cause it goes away when I add fuel.

 

[blackrosenova40]

Maybe your cam jumped the timing belt!

 

[DJ23GSX]

Maybe your cam jumped the timing belt!

From what my mechanic/dsm buddy told me even if it jumped one tooth the cas doesn't have enough adjustment to bring it back to 5*. Is that accurate?

 

[pauleyman]

Mechanical timing and ignition timing are two very different things. I would say yes the CAS needing to be so far out could be a symptom of a skipped timing belt. Go look.

 

[DSM's 4 life]

my cas is past adjustment to for some reason i just opened my throttle slightly to get it to .63

 

[steve]

my cas is past adjustment to for some reason i just opened my throttle slightly to get it to .63

I think your confused. Maybe you mean TPS? The CAS is a timing reference and isn't adjusted by voltage.

I recently replaced my alternator and upgraded my turbo (20g) and after putting it back together the car ran like crap and knocked all over the place. I checked base timing and for some unknown reason it moved from 5* to 10* after putting on the new alternator and turbo. As it sits right now my cas is maxed out just to get base timing down to 5*. Before the alternator died the cas was just about dead in the middle to get the base timing to 5*.

Have you double checked to make sure that the harmonic dampener (crank pulley) hasn't slipped? Turn the engine over by hand to TDC (Check by pulling plug #1 and see when the piston is at TDC) and make sure that the mark on the dampener lines up with the T on the front cover.

 

[DJ23GSX]

I think your confused. Maybe you mean TPS? The CAS is a timing reference and isn't adjusted by voltage.



Have you double checked to make sure that the harmonic dampener (crank pulley) hasn't slipped? Turn the engine over by hand to TDC (Check by pulling plug #1 and see when the piston is at TDC) and make sure that the mark on the dampener lines up with the T on the front cover.

That's a great idea thanks. I've seen what happens when the dampener separates the timing mark just keeps going around and around when you check the timing. My mark is dead on 5* but if it just slipped and hasn't separated that would make total sense. I'll have to to check that tomorrow. Will I have to crank the engine around a few times for the mark to line up with the T or does it line up every time its at TDC? I'm a timing noob so pardon my questions .

 

[EMX5636]

The #1 piston will always be up when the mark is at TDC. Which stroke doesn't matter for this test. Good thought on the balancer. I've been running a Fluidampr for long enough to forget about that problem.

 

[steve]

Correct, you can tell when it's TDC compression stroke for cylinder #1 when the timing marks line up and the dowels in the cams are at 12 O'Clock. At most you might have to rotate the engine 720° to find TDC compression stroke for cylinder #1 but TDC cylinder #1 happens once every 360°.

 

[DJ23GSX]

So I had a few minutes to check my crank pulley and cam gear timing marks. It looks to me like the cam gear marks line up perfectly. What do you guys think?

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I did the old screwdriver in the #1 spark plug hole to find TDC and while looking at the timing mark on the crank pulley as soon as it hits the T on the timing plate the screw driver stops moving up. It doesn't start moving down till its maybe a 1/4" past the mark. I'm guessing that's normal? So its looking more like the dead alternator might have fried the CAS or am I missing something else?

Thanks for the suggestions guys

 

[steve]

Sounds like the marks are correct. One thing down.

When you set the base timing was the engine up to temp, and idling at 750 RPM?
Was just the check timing connector grounded and nothing connected to the DLC?

 

[DJ23GSX]

Sounds like the marks are correct. One thing down.

When you set the base timing was the engine up to temp, and idling at 750 RPM?
Was just the check timing connector grounded and nothing connected to the DLC?

Yes the car was fully warmed up and idling right around 750 rpm's. I had the timing plug grounded and unhooked the pocketlogger from the diagnostic port. I never had problems with there base timing before the alternator died. The cas used to be right in the middle to get 5* . After installing the there new alternator it was idling like shit and popping so I checked base timing again and it mysteriously jumped to 10* and in order to get it back down to 5* my cas is maxed out. I'm out of adjustment with the cas and can't get base timing any lower than 5* now.

 

[pauleyman]

The cams still have to line up relative to the crank. Was the crank on the mark when the cams were on their marks?

 

[DJ23GSX]

I did not check the crank mark.I didn't have time to pull the lower timing cover

 

[pauleyman]

Then the test isn't valid. At least make sure the harmonic balancer lines up. It's crude but better than not looking. Think about it, what if the crank skipped one tooth? Cams would still line up of course but not relative to the crank they wouldn't. Car would still be way out of time. You could say that two ways. Crank is off one tooth or cams are off one each. The only way to check cams is to make sure crank is in time.

 

[DJ23GSX]

OK I should have some time Saturday to pull the lower cover and take a closer look.

 

[steve]

Then the test isn't valid. At least make sure the harmonic balancer lines up. It's crude but better than not looking

That was kind of the point of checking what lines up when cylinder 1 was at TDC.
I didn't like the note that the pistons didn't seem to move for a 1/4" of rotation of the harmonic dampener after TDC but it's been awhile since I've looked to see how much dwell there is.

 

[DJ23GSX]

since I might be a little confused at the previous posts this is a pic of where the crankp pulley timing mark is when the cam gear marks are lined up and the dowel pins are at 12 o'clock. If its hard to see in the pic the crank mark is right there near the 10 mark on the timing plate. That's not good I'm guessing?

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[pauleyman]

Time to take the cover off and look in my opinion.

 

[steve]

I guess you were confused as to what you were checking. The idea was to verify TDC from the pistons since you can't see the crank timing mark and check that all the visible timing marks lined up at that point.

If the crank pulley lined up with TDC based on the screwdriver but the cams weren't in the position that you showed then the timing has jumped.
If the cams lined up at TDC based on the screwdriver but the crank pulley reads 10* like the latest picture then the crank pulley has slipped. It's not possible for timing to jumped jumped if the piston says the crank is at TDC and the cams line up with the dowels up.

You must reference where things are at TDC for your data to have any meaning.