new cam sensor installed CORRECTLY runs but not good

[Heg87t]

You're right...

Reference: posts 17, 33,37,
you shouldn't hijack someone elses thread...

You are right. :redface: I thought the picture might help the original quesiton but it ended up going off in the wrong direction.

My apologies.

 

[Chuck Leeper]

U r ..

You are right. :redface: I thought the picture might help the original quesiton but it ended up going off in the wrong direction.

My apologies.

sentenced to 3 burnouts of more than 100'! Once completed, you must have at least 1 beer!
Wrong direction seems to be getting more and more common on most of the boards I visit!

 

[Chuck Leeper]

U r ..

You are right. :redface: I thought the picture might help the original quesiton but it ended up going off in the wrong direction.

My apologies.

sentenced to doing 3 burnouts of more than 100'! Once completed, you must have at least 1 beer!
Wrong direction seems to be getting more and more common on most of the boards I visit!

 

[pacecarta]

the pic does help , i took a pic to show the OP but could find my flash drive to load it up from my phone, but im done with the OP he should have gotten his sensor corrected by now , and this is on topic so if you're back from penance of doing burnouts to appease Chuck ill chime in

as asked we need to know if you are 25* Atdc compression stroke , if so then yes your pic shows it will have the stock cap installed 180* out of phase and actually set on the tdc of the exhaust stroke (thats if you had the cap aligned with the tab since it can be put on 180 even though its tabbed but wont sit flush as intended by gm )
just loosen the cam sensor bolt at base ,twist the body 180 degrees, and tighten down , reinstall the cap aligning the tab on cap to tab on base ..thats it

now if you had set balancer at 25 ATDC compression stroke and pointed the dot on the cam gear at the pass fender before dropping in the sensor window edge would end up at approx 4:00 on the closest edge to the radiator , then when the cap goes on the wires would be as done at the factory and be at the 4:00 position , but position of wires isnt really important as long as the sensor body (which also aligns the cap) is indexed based on where the window is

 

[Just a Six??]

I cant understand with all the reference articles, the search feature & the help provided by members how this Cam Sensor topic comes up so often? Every Newb should be forced to buy a list of scan tools that would be under $1k in order to even own one of these cars. It should be mandatory for things like the Caspers tool, Scan master, fuel pressure guage, pump & hotwire etc. You know what I mean. Along with mandatory 25 hours of reading at GNTtype.org & vortexbuicks-etc.com I was NO Expert when I got mine in 88 & learned with books etc. Kirban sold the Steve Dove Guide to GN's & had all the part numbers, diagrams & lots of great reading. I have at least 250 passes at the track from 90-92 & never tore up anything (except tires!) running mid 12's. Not super fast by any standards but for my knowledge I was happy my stocker would do that.
Now with the internet there is NO Excuse for these kind of questions. I know a Newb likes to ask & thats great but the common questions that have 5000 hits about them like Cam Sensor is not one that needs to be asked.
Sorry for the rant but it gets old & many guys wont even try to help when it has 5000 posts already.
Back under my rock.
Cheers!

 

[Heg87t]

sentenced to 3 burnouts of more than 100'! Once completed, you must have at least 1 beer!

Thanks guys!! :smile: I don't have my posi installed yet so does the 3 burn out rule mean I have to do 6 with my one tire?? That would be ok since it means two beers afterward. :tongue:


I brought the engine up to TDC compression with the balancer mark at 0 on the timing tab and took this picture while leaning over the left fender not from the front.
I use the stock GM cap NOT a Caspers cap.

I am going to pull the left valve cover off tonight and remove and reinstall the cam sensor to make sure it's right. I understand how to do it much better after reading this thread.

 

[bmackinnon]

I am going to pull the left valve cover off tonight and remove and reinstall the cam sensor to make sure it's right. I understand how to do it much better after reading this thread.

You don't have to pull the valve cover to verify tdc on the compression stroke, just put your finger over the #1 spark plug hole while you rotate the engine as the timing mark on the balancer approaches the timing tab. You'll definitely know which rotation is compression... especially if your finger is IN the hole and the wife hits the starter a bit too long!!

 

[Heg87t]

You don't have to pull the valve cover to verify tdc on the compression stroke, just put your finger over the #1 spark plug hole while you rotate the engine as the timing mark on the balancer approaches the timing tab. You'll definitely know which rotation is compression... especially if your finger is IN the hole and the wife hits the starter a bit too long!!

Yeah I could do that too but I was using this as motivation to retorque the heads at the same time. :tongue:

I spent my lunch hour reading about the setting procedures and pondering which option to use:
1) Remove the stock GM cap, grind the locator tab off the inside, rotate the cap 180 degrees and reinstall.
2) loosen the hold down bolt and rotate the sensor body 180 degrees
3) Go through the full procedure to find 25 ATDC, remove sensor, and reinstall correctly.

Right now I am thinking option #1 tonight to get it running correctly when I drive it this weekend to do my burn outs :biggrin: then do #3 when I have time.

 

[pacecarta]

if you were at 0* tdc in that pic go with idea #3 ,

but you dont need to pull the sensor body out unless you care where the wires end up

 

[Heg87t]

if you were at 0* tdc in that pic go with idea #3 ,

but you dont need to pull the sensor body out unless you care where the wires end up

Yes, the picture was at 0* TDC compression stroke.
Do you think I am not just 180* out but 155*or 205* out?

I don't care about the wire position right now.

 

[pacecarta]

vortexbuick-etc cam sensor install
nuff said

 

[bmackinnon]

......and pondering which option to use:
1) Remove the stock GM cap, grind the locator tab off the inside, rotate the cap 180 degrees and reinstall.
2) loosen the hold down bolt and rotate the sensor body 180 degrees
3) Go through the full procedure to find 25 ATDC, remove sensor, and reinstall correctly.

Definitely NOT #1 or #2. I, for one, am pretty damn sure you are not 180 out.... and if you were 150 or 205 or whatever out, it would run like a$$, if at all... kicking, farting, backfiring, etc.... Just mark the balancer at 25 deg atdc, rotate it to that spot, loosen the bolt, connect the voltmeter, move the sensor a hair right, then a hair left to VERIFY it's correct, re-tighten, done..... should take all of 1/2 hour if you are slow like me..... :wink:

 

[Heg87t]

Pulled the sensor this afternoon and started over to reset it. Idles much better and the throttle response is improved also.
I think the sensor has been 180 out since I got the car causing it to idle and run bad.

Much better now.

Thanks to all for the advice.

 

[bmackinnon]

So WAS it definitely 180 out? .... and you ended up reseting it by pulling the sensor, rotating the motor 1 revolution and dropping it back in... and then of course, setting it by following the 'turn till the voltage drops' methodology?

 

[Heg87t]

So WAS it definitely 180 out? .... and you ended up reseting it by pulling the sensor, rotating the motor 1 revolution and dropping it back in... and then of course, setting it by following the 'turn till the voltage drops' methodology?

Yes. I first turned the body of the sensor 180* and the idle was better immediately. Smoothed out and didn't load up as I let it idle for a while. Took it for a quick drive and it pulled a lot better. Had a little stumble in it when I would accelerate.

Based on that I decided to do the full setting procedure to make sure it was right.

Drove it about 200 miles today and it ran well with no issues. Still a little stumble and it will sound the Caspers knock alarm if I roll into it half throttle at about 6-8 pounds boost. Full throttle it pulls well with no knock.
Next step is to finish hooking up my fuel pressure gage to verify function of the pump. Going to order a Turbo Tweak chip in a couple of weeks also.

Been trying to figure out the damn bad idle for 6 months now. I think the darn thing has been 180* out since I have owned the car. Guess I should have started with verification of the basics. Live an learn. Thanks for asking.

 

[JayC]

I must be missing something here. By your procedure, how do you compensate for the oil pump gear's location? You have to manually move the oil pump or else youre not longer in the correct position for the sensor to drop in.

Ive yet to see anyone actually reference the factory correct procedure for setting the sensor. Maybe its in one of those articles linked, I didnt look.

I set them via the factory procedure. Yes it takes longer but its dead on when you set it that way. I dont see where the Caspers tool makes a whole lot of difference. It essentially just takes the place of your voltmeter. Everything else has to still be lined up correctly. It is nice for setting them on the engine stand but in the car, it doesnt make much difference.

the pic does help , i took a pic to show the OP but could find my flash drive to load it up from my phone, but im done with the OP he should have gotten his sensor corrected by now , and this is on topic so if you're back from penance of doing burnouts to appease Chuck ill chime in

as asked we need to know if you are 25* Atdc compression stroke , if so then yes your pic shows it will have the stock cap installed 180* out of phase and actually set on the tdc of the exhaust stroke (thats if you had the cap aligned with the tab since it can be put on 180 even though its tabbed but wont sit flush as intended by gm )
just loosen the cam sensor bolt at base ,twist the body 180 degrees, and tighten down , reinstall the cap aligning the tab on cap to tab on base ..thats it

now if you had set balancer at 25 ATDC compression stroke and pointed the dot on the cam gear at the pass fender before dropping in the sensor window edge would end up at approx 4:00 on the closest edge to the radiator , then when the cap goes on the wires would be as done at the factory and be at the 4:00 position , but position of wires isnt really important as long as the sensor body (which also aligns the cap) is indexed based on where the window is

 

[darkred87T]

Two turns of the crankshaft =1 turn of the camshaft right?. TDC is both valves closed and piston all the way up in the cylinder. I just pull the valve cover and watch the rockers.

The cam sensor is supposed to be set at 25 DEGREES ABOVE/AFTER TOP DEAD CENTER. The notch in the balancer passes the "0" mark on the timing chain cover (going clockwise) and winds up 1.45" past it for 25 degrees ATDC. The light on the cam tool or cap should light up at this time. Turn the cam sensor clockwise until light goes out, then counterclockwise until it just lights up.

The Capsers cam tool comes with very detailed instructions on how to set the cam sensor. Read carefully.

 

[oldtimer]

"Quote"

And I suppose you tell us next that you also walked to school 10 miles...uphill...both ways.

Ya, and in our family, there was only one pair of socks. First one up in the morning got to wear them. Made the 10 mile walk to school in the snow a little more tolerable.:biggrin:

George

 

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