cps=camshaft or crankshaft

Im about to go through the pain to install a crankshaft positioning sensor, just making sure I'm not supposed to be changing the camshaft. since both are abreviated cps

swebilius said:

Im about to go through the pain to install a crankshaft positioning sensor, just making sure I'm not supposed to be changing the camshaft. since both are abreviated cps

Click to expand...

CPS is generally used for the bellhousing mounted "engine speed" sensor. The distributor (camshaft) sensor is actually called "synch signal generator" and in one manual I saw it abbreviated "CKS" or something like that. Renix will actually run without the CKS (synch signal generator) but it will not be happy "guessing" where #1 is. CPS, will not run at all if the signal doesn't reach the ECU. The hall-effect ensor itself is very hearty but the wiring/connectors are very lame.

OMT - The camshaft (CKS) usually only appears in "ignition" sections and the "Crankshaft Position Speed" sensor is usually found in the fuel injection ection of most parts books.

my 94 4.0 is stalling while driving and not showing any computer errors. Everyone has told me to change my cps. So I bought the crankshaft sensor and waiting for somebody with tiny arms to get to some bolts.

swebilius said:

waiting for somebody with tiny arms to get to some bolts.

Click to expand...

Remove the crossmember under the transmission mount and lower the entire rear of the engine/tranny a little with a floor jack. Just watch for stuff getting pulled but this usually helps reach bolts. Don't drop one down in the flywheel housing or you will have a very, very long day.

Good thinking.

The Crankshaft Position Sensor (CPS) is located at 1100 on the bellhousing, looking forward. You will be well served with about a 24" extension for your ratched, and a little time spent notching the sensor bracket can help - you won't have to wrestle the bolts in along with the new sensor. A 7/16" or 11m/m (same size) socket with the inbuild universal joint won't go awry, either.

The Camshaft Position Sensor (properly abbreviated SYNC) is located inside the distributor, requring the distributor to be dismounted and disassembled in order to replace it. I've not seen a bad one yet - it's in a pretty friendly environment.

The CPS is responsible for generating timing pulses for fuel injection and ingnition events. It generates a total of six "trigger" pulses and a number of "warning" pulses every twice around.

The SYNC sensor is responsible for basically one thing - telling the ECM when cylinder #1 comes around. The system can function without the SYNC sensor - mainly by "guessing" when #1 is firing, and adjusting it's "guess" until the engine runs - although not terribly well.

Now, when I refer to "notching" the CPS bracket - here's what I have in mind...


(I know, I know - it's a little fuzzy. I'll take a better one one of these days - using the box underneath it as a background confused the autofocus...)

Note that the bracket has one notch extending downward, and one going straight out toward the end. The one notched straight out is the bottom hole, and the idea here is that, with the bolts loosened slightly, you can slip the end of the bracket onto the lower bolt, tilt the thing into place, and use a stick or a long screwdriver to rest upon it to hold it in place while you tighten the bolts. To remove, loosen the bolts and pull the wire. This is now a standard practise here - it's got changing the CPS knocked down to about 10-15 minutes - down from about an hour and a half of sweating and swearing! Significant improvement.

The notching takes about two minutes with a Dremel - five if you're not famiiar with Dremels yet. Be careful to not change the size of the bolt holes - just extend them.

5-90

5-90 said:

Good thinking.

The Crankshaft Position Sensor (CPS) is located at 1100 on the bellhousing, looking forward. You will be well served with about a 24" extension for your ratched, and a little time spent notching the sensor bracket can help - you won't have to wrestle the bolts in along with the new sensor. A 7/16" or 11m/m (same size) socket with the inbuild universal joint won't go awry, either.

The Camshaft Position Sensor (properly abbreviated SYNC) is located inside the distributor, requring the distributor to be dismounted and disassembled in order to replace it. I've not seen a bad one yet - it's in a pretty friendly environment.

The CPS is responsible for generating timing pulses for fuel injection and ingnition events. It generates a total of six "trigger" pulses and a number of "warning" pulses every twice around.

The SYNC sensor is responsible for basically one thing - telling the ECM when cylinder #1 comes around. The system can function without the SYNC sensor - mainly by "guessing" when #1 is firing, and adjusting it's "guess" until the engine runs - although not terribly well.

Now, when I refer to "notching" the CPS bracket - here's what I have in mind...

(I know, I know - it's a little fuzzy. I'll take a better one one of these days - using the box underneath it as a background confused the autofocus...)

Note that the bracket has one notch extending downward, and one going straight out toward the end. The one notched straight out is the bottom hole, and the idea here is that, with the bolts loosened slightly, you can slip the end of the bracket onto the lower bolt, tilt the thing into place, and use a stick or a long screwdriver to rest upon it to hold it in place while you tighten the bolts. To remove, loosen the bolts and pull the wire. This is now a standard practise here - it's got changing the CPS knocked down to about 10-15 minutes - down from about an hour and a half of sweating and swearing! Significant improvement.

The notching takes about two minutes with a Dremel - five if you're not famiiar with Dremels yet. Be careful to not change the size of the bolt holes - just extend them.

5-90

Click to expand...

Just curious about the notching. Does this work even with the plastic dust shield? The CPS's I 've bought came with a replacement snap-in dust shield, and I found that when that is used, it retains the CPS in its position before the bolts go in, and makes it a good deal easier to install. Can you still tip in the CPS with the shield in place?

Dunno - I've never had that dust shield.

I do need to work on some sort of wire guard - that one I took pics of? Nothing wrong with it - other than needing to attach two new wires to replace the melted ones... I think that sensor would be better mounted at 0100 than at 1100, but what do I know...

RULE - NEVER run critical wiring anywhere near the exhaust manifold, unless it is totally unavoidable...

5-90

5-90 said:

Now, when I refer to "notching" the CPS bracket - here's what I have in mind...

http://us.f1.yahoofs.com/groups/g_14019275/Notched+CPS+Bracket.jpg
(I know, I know - it's a little fuzzy. I'll take a better one one of these days - using the box underneath it as a background confused the autofocus...)

5-90

Click to expand...

Could you repost this image or email it to me... for some reason it doesn't display in your post, and if I cut and paste the URL into the address box of another browser window, I get an error message saying I don't have permission..

Thanks, Rick

OK - here goes...



Ain't the cleanest image, but it gets the point across.

5-90

XJXJ said:

Remove the crossmember under the transmission mount and lower the entire rear of the engine/tranny a little with a floor jack. Just watch for stuff getting pulled but this usually helps reach bolts. Don't drop one down in the flywheel housing or you will have a very, very long day.

Click to expand...

Yep. I had a very long day when I did mine. Nothin' like rootin around with a magnet in your bell housing.

could heat shrink tubing be the answer to shoring up cps wires?

never even seen a cps but need to replace anything that'll leave me stranded - my '98 has 105k on it and hopefully will see regular trips from LI, NY to northern NH.

thanks

sv

5-90 said:

OK - here goes...

Ain't the cleanest image, but it gets the point across.

5-90

Click to expand...

Does not show up for some reason... hmm. Guess I'll have to use my imagination! Thanks for trying. -Rick