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what is cps and where is it

cps is the crank position sensor. It tells the ECU what the position of the crank is.
Without it the ECU won't fire the coil, and you won't get any spark.
Check to see if you have spark while cranking. If you don't then the CPS is a good bet.
It is located at the 11 O clock position on the bellhousing, looking toward the front. It's a PITA to get at, you'll need an assortment of extensions and some u-joints.
You should also check the CPS connector for corrosion, sometimes replugging it will fix it.
 
CPS - crankshaft position sensor, its on the back of engine
 
the CPS is mounted at the front of the bellhousing for the transmission, drivers side.
 
whats the best way to check this and would this keep it from starting? do you suggest checking something else the valve stem on the fuel bar spays gas when i push it, it bleeds out then i crank it over again check the valve stem again and can make it spray with pressure again, so i think maybe the fuel pump works.
 
ya fuel pump works , but how much pressure?

and yes the CPS will stop from starting., it sends a signal to the computer.
 
Is the valve stem on the fuel bar where you check fuel pressure? How much should it have? what tells it whether it has enough pressure or not.
 
yes that's where you check pressure.
You need a fuel pressure guage that reads up to about 50 PSI.
My 87 is supposed to be 31 PSI with the fuel pressure regulator vac line attached, 39 PSI without. I don't have numbers for your HO, but that should put you in the ballpark.
 
would the fuel pump quit all at once? seem like when I started it that morning it reved up pretty high untill I put it in gear, then it seemed normal no other warnings. I did notice it rev up which I thought was abnormal but paid it no mined and drove on to work, or at leased I tryed.
 
possible. have you checked all the fuses?
I think that you need to elaborate what happened when it died. And what you've checked.
Check all the fuses and relays first.
Make sure that the CPS connector isn't nasty, in fact just unplug and replug all the wires connected to the engine.
Check that the CPS harness hasn't fallen against the exhaust and melted.
Verify that the motor is getting fuel.
Verify that you've got spark.
If it has spark and fuel it will start. You need to figure out which one of the triangle of fire you're mising to diagnose further. Spark is the easiest one to determine. Find out if the coil is firing spark plugs and report back. I'm willing to bet you've got no spark, and if that's the case the CPS has likely failed. It is known that the CPS can just die, and when that happens the motor will quite just as if you turned the key off.
 
can I jump or bypass the cps to see if thats the problem. this rig just shut off driving down the road at55 mph, I've had no problems at all with this. I think I have located the cps and there really is a good way to get to it, I can get my hand on it from the bottom side bearly. I did unpug the plug and pluged it back to check for bad connection.
 
I had the same problem. Popped the hood and I instantly saw that the wire from the coil to the distributor had come off the coil and was just sitting on top of it. Not trying to insult your intelligence, just reminding you to check the simple things first.
 
My '96 has 49 PSI at the fuel rail. Don't know when it changed from the 31/39 that 87manche posted, but I'd call a dealer/garage to check.

Just replaced CKS/CPS on mine today chasing random rough run & misfires. Took care of most of it. Starting new thread related to your thread, subject will be:
Crankshaft End-Play?
 
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When changing the CPS, remove the front driveshaft, it'll make it a whole lot easier to get at. I used a 20" extension from craftsman and a u-joint.
 
I just replaced my CPS. My 96 just flat out quit a couple times after about 45 minutes of operation. After waiting about 30 minutes it would start and run for another 7 hours with no problem. Another thread said the CPS can put out a marginal signal which will kill the spark, but not show on the OBD-II as a check engine signal.

I got it out and back in using a 12 inch extension with a swivel end. Putting the bolts back was easy. I forced the heads into the sockets with a piece of typing paper to hold the bolt head in the socket. Removed and replaced the CPS in less than 20 minutes.
 
my rig has set for over 2 days and still wont fire, so what ever it is it's dead. I've tried the turn key for 10 sec trick and that didn't work also I've checked connections at the coil and several other places. I was hoping someone would know how to jump or bypass the cps so I could try that.
 
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