Cam positioning sensor

[Justang2k]

how does it work?

I'm gonna have my cam installed by a shop (engine will be out of the car). How do I make sure that the cam positioning sensor will be working properly when I start the car?

[Justang2k]

do I need a special tool?

[pb_milan]

either the thing works, or doesn't.
it should be ok.
if your car runs now, it'll run later

mark the timing cover when you pull it out, and line it back up in the same position and you won't need any special tools.

[Justang2k]

cool. that's what I wanted to know. I don't like going into projects blindly.

but wait. I'm going to a 4.2L engine. All my 3.8 stuff is going to go on the 4.2 short block. does that make a difference?

I don't know. that's kinda why I wanted to know how it worked. I've heard of people messing things up with the cam sensor.

[pb_milan]

you can't really mess anything up (break anything) by putting it in wrong.

the car just won't start.
there is a special little tool that sets it in the right place.
i'm pretty sure if both engines are a TDC when you take it out/put it in, that it should be ok

i put that thing in wrong when i swapped to a 4.2 L :)

i just kept turning it and rotating it blindly (without a tool) until i got the car running nicely

later one when i got my hands on the tool i set it right (i was close)

[Justang2k]

ahhh yes, the technical way of doing things! :headbang: cool.

well I'll try the TDC thing. thanks

J

[1kwik6]

Actually, the car will start if it's off.Mine is still off a little bit, and it runs fine, but the cel is on.

[pb_milan]

Actually, the car will start if it's off.Mine is still off a little bit, and it runs fine, but the cel is on.

the car will barely run if its 20* off. it won't run at all if its over 30* off

[Justang2k]

heres the deal. My 4.2 is at the machine shop. they are putting it back together. but they informed me that I would have to put the cam positioning sensor in myself. So, I don't know where the sensor should be.

what do I need to get it back on correctly.
do they rent these tools at like an Autozone or something like that?

I'd like the engine to be perfect when I get it back in and all. if they rent these some place, then I'll just do that.

[1kwik6]

you can get the tool from Snap-on.

[Justang2k]

how much money is it gonna cost?

I need something super cheap.

[1kwik6]

Snap-on is never cheap.

[Justang2k]

yeah, that's why I stated I wanted somthing cheap.

I once bought screwdrivers from them.... WOW

anyway, can you rent these tools?

[1kwik6]

Not that I'm aware of. "Vato-zone" doesn't have them. Not sure about O'reilly's though.

[Red6Banger]

I looked at pics of the tool and I can't tell that it does anything. I positioned my postion sensor without one. There used to be a writeup on this board about it. I have hardcopy at home and will look to see if I can find it. What year is the position sensor/car? You use different angles depending on the year.

Here is the procedure from memory:

With the serpentine belt and spark plugs removed, stick your finger in the #1 plug hole while rotating the crank by hand. when you feel compression in #1 continue rotation till the piston hits the top of it's stroke. This ensures that you are at top dead center of compression stroke. The line on the harmonic balancer should be at 12:00. You should be about halfway between holes in the harmonic balancer. continue to rotate the crank clockwise until the 2nd (? this is where the memory becomes fuzzy) hole is at 12:00. Then insert the crank position sensor (CPS) with the top removed and the plug is at 38 degrees (this is the part that varies by year, this is for a 94) from straight with the engine centerline. Now turn the vane such that the a line between the ends of the vane would also be at 38 degrees (lines up with the center of the plug) and the vane itself is toward the back of the motor. Some of this is a little tricky since when you insert the CPS the curved teeth make it move some. The degrees listed above should be when fully inserted. Now tighten it down per the torque specs and replace the cover.


I am a little fuzzy on this so if anyone else has the procedure for it without the tool, feel free to join in. I found it helpful to use Powerpoint to draw a 38* angle and print it out as a guide. I guess that's what the tool helps with. Also I don't know the details of the 96-98 vane which is a different angle and the vane isn't fully 180.

Hopefully my description and cloudiness have confused you sufficiently that you will search in the engine forum for "cam position sensor". I got a bunch of hits, some of which include diagrams.

Here are some good ones:

http://v6power.net/forum/viewtopic.php?t=14989&highlight=cam+position+sensor
http://v6power.net/forum/viewtopic.php?t=1114&highlight=cam+position+sensor
http://v6power.net/forum/viewtopic.php?t=1025&highlight=cam+position+sensor
and here's one on the tool
http://v6power.net/forum/viewtopic.php?t=1025&highlight=cam+position+sensor

[Justang2k]

what if you don't take the cam positioning sensor out?
then do you have to use the tool?


I pulled the engine, and the #1 was at TDC. But it wasn't on the compression stroke. both keyways were at 12o'clock. that was on the 3.8 motor. now I took the front over off the 3.8 and put it on the 4.2 motor. I don't know what the 4.2 was... I forgot.
Then I took the whole thing to the machine shop. They say they don't have the tool. so i have to do it myself.

so if they haven't taken the sensor out of the front cover, do I have to mess with it?

[Red6Banger]

It has to be synced with the cam. That's why the check for TDC (and why they call it a cam postion sensor :D ). The position with the cover has nothing to do with it except to be sure that the actual sensing part is at the correct location in the rotation of the vane.

[Justang2k]

cool. I'll have to locate a sensor tool.

[mattd]

When i did my cam swap i tried to put the CPS back to where it shoud be(using the special tool). So when i took my car to ford for a recall i asked them to check the CPS to make sure it was on correctly. Well, it was off by 180 degrees, but the car seemed to run fine. My suggestion to you is to take it to ford. Its only a 1/2 hour job so it won't be that much. Thats my suggestion.

[Red6Banger]

The 180* problem is apparently the most common error. That's why I said TDC of the COMPRESSION stroke. If you use the exhaust stroke, you are 180* off. That's why you stick your finger in the spark plug hole. You should be able to tell the difference between compression and exhaust.

I am surprised it ran at all with the 180* error, much less well. The computer would have been firing the the injectors during the power stroke rather than the intake stroke.

[Justang2k]

seems to reason it would run alright. the fuel would just sit on the intake valves till they opened up again. probably not the way to make the most power though.

but yeah, that might be more economical. Just take it to Ford once I get it running decently.

[Justang2k]

mattd: would you happen to have the special tool still?
where did you get it?
how much was it?

[gitman]

Not that I'm aware of. "Vato-zone" doesn't have them. Not sure about O'reilly's though.

lmao i've never heard that one before, thats good :laugh:

[1kwik6]

Not that I'm aware of. "Vato-zone" doesn't have them. Not sure about O'reilly's though.

lmao i've never heard that one before, thats good :laugh:


Thanks, I try. :p

[mattd]

mattd: would you happen to have the special tool still?
where did you get it?
how much was it?

I sold the tool to V6sprout and i paid $30 CDN from Ford. They don't usually sell tools. But since i'm a frequent customer they ordered it for me.