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98 Catera Crankshaft Position Sensor Replacement - Cranks Won't Start

102K views 71 replies 42 participants last post by  nika 
#1 · (Edited)
The procedure to replace the Crankshaft Position Sensor (CPS) is below with pictures - you can skip these first sections if you choose, its mostly my ranting.

My Symptoms: Here’s what my car did. The problem started with occasionally taking longer cranking before it would start. Then it sometimes would crank, but not start at all after it had been running (or sometimes start with alot of cranking). I could wait 5 minutes, 30 minutes, an hour, or overnight and it would start – it seemed to be random on when it did it and how long I had to wait. This went on for a couple months, with it happening more severely and more frequently, but still random and intermittent. Then one night after work, it wouldn’t start at lunch. When I went to leave in the evening it still wouldn’t start. I tried disconnecting the battery for 30 minutes, but that didn’t work. Next morning, still no start. Had it towed to the dealer, they replaced the fuel pump ($800!!! I’ll rant about this in a minute). The car ran fine for almost two weeks, and then started the same symptoms. This time it only took a few more weeks before it wouldn’t start at all. This time it was at home. It was getting no spark. I disconnected the battery and charged it and when I reconnected, it started right up. After one day of driving, it again wouldn’t start at home. After checking for fuel (fuel pump was working) and spark (no spark) and trying other stuff, the battery was low. I disconnected the battery and charged it and it started. So I was thinking that disconnecting the battery was resetting something, so I drove it to work. It wouldn’t start – I disconnected the battery for 30 minutes, then an hour, then overnight while charging the battery, and still crank but no start. I had it towed home. I installed a new Crank Position Sensor (CPS) and it started right up and has been fine for almost 2 weeks now. Some other people had there CPS cause the car to die while driving, or go out all of a sudden. Mine apparently was intermittent for several months. And its important to note that it always cranked normally, and the engine light never came on. And when it did start, it always ran perfectly fine – this was the most confusing to me and the reason this dragged on for so long.

About the Cadillac Dealer Shop (a certain, unnamed dealer shop on the north side of Indianapolis...Tutwiler...oh, did I say that out loud?): So from my story above, I had it towed to them and they determined that it was the fuel pump. I asked if they scanned it – they said they had and that it had no codes. I asked how they knew it was the fuel pump – they said that when they hit the fuel tank with a rubber mallet while cranking the car, they could hear the pump spin up for a second. Ok, that sounds reasonable. I took them at their word and coughed up the $800 bucks – I would have attempted this, but my wife was eight and a half months pregnant and I wanted my car to be ready for THE CALL – and I didn’t really have time to mess with it. So I’m sure its possible that the fuel pump and CPS were going out at the exact same time. And the first no start was caused by fuel pump and the subsequent no starts were caused by the CPS – and they just happened to have the exact same intermittent symptoms... yeah, right. OR maybe the dealer just suspected an intermittent pump and threw one on. Even if the pump was bad (and I doubt that it actually was) they still did a poor job diagnosing the problem. The CPS is a common problem on Cateras with these symptoms. The justification for the astronomical labor rates is proper equipment, training and experience to work on Cadillacs. They obviously didn’t have any of this in my case since my problem was mis-diagnosed, or at the very least, incompletely diagnosed (assuming the fuel pump was bad). I thought I was paying for premium service – what I got was royally screwed. Oh, but they do have a “free car wash with service” policy, so I did get my car washed – it only cost me $800. Fantastic. Next time I’ll take my chances with a random mechanic – I may still get screwed, but at least it won’t cost as much.

A quick note about the Service Manuals for anyone that is considering buying them: I’m a novice mechanic, so maybe its just me – but the service manuals don’t seem to be as useful as I thought they would be. The diagrams are often useless – It took me over an hour of looking at the CPS connector diagram and staring at the engine from every possible angle before I found it. And the procedure doesn’t tell you to remove the wiper arms or vent; I don’t see how you could possibly get to the connector without removing them. The index of the manual does not even come close to listing all relevant sections that pertain to the part\term you are looking up. There is alot of very useful info, but its difficult to find and sometimes incomplete.

Crankshaft Position Sensor Replacement

[See picture 1]
The first step is to remove the windshield wiper arms. A tip that I thought of too late: use tape on the windshield to mark the angle at which the arms are attached. Remove the round plastic cap, then the nut from each arm. The arm is wedged onto the cone shaped bolt, so you have to use some force to work it loose. The manual says to - grip the arm with both hands and use a rocking motion - whatever that means. Use some force and pull the arm back and forth in the direction that the windshield wiper would normally move. Eventually it will break loose and move pretty freely. You then have to relieve the tension from the spring-loaded hinge on the arm to be able to lift it off the bolt. You'll figure it out. Make sure to remove the round foam-rubber rings that are under the arms. You don’t want to knock one off and drop it down into the engine compartment and then into a hole in the frame, never to be seen again... not that that happened to me or anything. Tip: use a rag or towel to keep the arm from rubbing/banging against the hood.

[See picture 2]
Next remove the plastic vent cover at the base of the windshield. There are about 5 plastic screws under the rubber seal at the bottom of the windshield. The picture shows one of these screws in the locked position. Rotate the screw 90 degrees to unlock it and it pulls straight out. Use needle nose pliers (or whatever) and pull these screws out - otherwise you'll break half of them when you pull the vent cover off. There's one additional screw on the driver’s side that holds the vent cover to the car body. The driver's side of the vent cover should now be able to be removed - there's about a 2-foot section on the passenger's side that is separate and doesn't have to be removed.

[See picture 3]
With the vent cover removed, you should be able to dig behind the engine and find the CPS connector, but just barely. Look at the picture below.

[See picture 4]
The big connector in the middle was in my way, so I disconnected it and pulled the two ends out of the way. Look at the next picture and you can see the two connector ends pulled out of the way.

[See picture 5]
The CPS sensor is attached to the back of the aluminum bracket In the middle of the picture. It takes a little work to get the clip off the metal bracket, and then get the clip and CPS connector to a position you can unclip them.

If you’re unsure about whether the CPS is the problem, you can try this (I thought of this too late, but you can learn from my mistake). Just drop the new sensor down the back/side of the engine, attach it to the engine, and plug in the new sensor. If the car starts, you can remove the old sensor and route the new sensor along a more permanent route. If it doesn’t start, something else is the problem.

To remove the old sensor, unbolt it from the engine block. The sensor is right next to the oil filter, is sort of egg shaped (round, but wider on one side than the other) and held on by one bolt. If you get the car on jack stands or ramps, you should be able to easily see the oil filter and CPS by getting under the car right behind the driver’s side tire.

An aluminum heat-shield sleeve covers the first section of the CPS wire. The original routing of the wire seems to pinch the sleeve between the oil cooler lines and the engine block. This makes removing the old wire a bit difficult. Here’s what worked for me. Once you pull the sensor off the car, twist the sensor so that the wire twists and breaks free from the heat shield. Then cut the wire at the sensor end. Next, pull the connector end to pull the wire free from the car. I had to twist the connector end as I pulled to get it to come loose. And the shield didn’t come out, just the wire – I don’t lose any sleep over having the empty shield still in there.

[See picture 6]
Next you have to route the new CPS wire. You can see the general path from the stick in the picture. I placed my work light on the top of the engine at the back, then got under the car and looked up to be able to see the general path. From under the car, I ran the stick up the back of the engine and out the top. I then taped one end of a piece of speaker wire (that was a little longer than the CPS wire) to the end of the stick and secured the other end of the wire to the windshield wiper arm. I pulled the stick down and used the speaker wire to figure out my path. Make sure the final path of the CPS wire stays clear of the exhaust manifold – I also tried to avoid the coils as much as possible to minimize signal interference (I don’t know if this is a big deal or not). Then I attached the sensor connector to the wire end under the car and pulled it up and plugged it in. Make sure the CPS wire is routed where you want it and install the sensor and bolt it in. (-Bonus Question: what’s wrong with the picture above – besides the piece of wood sticking out the top of the engine of course?)

Install everything in reverse order – reattach the CPS connector to the clip and attach to the bracket – reconnect the big connector that was in the way – install the vent cover (this can be a bit tricky to get aligned) – install the windshield wiper arms (use the tape marks to line up the arms, or make a rough guess like I had to do) – fire this bad boy up!
 

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#29 ·
I had the same symptoms - the car would start and run perfectly, then die while driving, or fail to start on several long cranks, then kick right over. It was the CPS. I had the car at my local mechanic for a week and he couldn't figure out what was wrong. I checked this forum and then my dealer replaced after I told them what it was.

it's a major and totally incompacitating inconvenience.
 
#30 ·
Perfect symptom description...Perfect connector and CPS location pix....Found sensor at a local in-stock Mom-and-Pop parts place for $45...Auto=Zone and Murray's were both $85....ALSO...Murrays loaned me the "Mac Tool? to diagnose the problem throught he OBD2 connector..for FREE...
Thanx Agian....Problem fixed for less than $50..Not including the $150 towing...
Final Comment....Why in the world was the "Check Engine" light not programed to illuminate?
 
#31 ·
Thanks to SIRMQC for the post on the crankshaft position sensor, his sage advise just saved me $1400. Own a 2001 Catera with 60+K miles. I've been through all the horror stories of buying new tires every 6 months because of uneven tire wear, $4500 to fix the AC and others. It got to the point that I was telling the Cadillac folks what the problems were. Anyway the other day I'm driving down the interstate at 70+ when the car dies. Had it towed to the local shop and they thought it was a fuel pump relay. Car ran for about 45 minutes then quite. They gave up so had it towed to Cadillac dealership. Prognosis was bad fuel pump, $1400 dollars to replace. I read SIRMQCs post and gambeled it was the CPS and replaced it myself. Drove the car today and it appears fine. It is an easy fix as long as you don't try to route it behind the oil cooler lines which is what I believe causes this problem to begin with. I followed the advise of others and tied it off away from the exhaust manifold and just cut the connector off one end of the old one and pulled it out.
 
#32 ·
Thought I would add my story to this thread as way of saying thanks. The information here solved my problem.

Well, it finally happened to me. I have never been afraid to jump in my Cat and ripoff a 400 mile day. Now I'm not so confident. Last night I went out for a bite and she dies while backing out of the parking spot. When I started her in the garage she stalled. I thought I just hadn't kept the starter on long enough. The engine caught quickly the second time and off we went. There were a few stops before the diner and she started fine each time.

When she did die there was no CEL but the Sport light (s inside a cog) was flashing. I have a ScanGauge installed and immediately checked for codes. There were none. Still, from hanging out here and learning, I'm sure it was the CPS. The engine would crank strongly. I replaced the battery 2 months ago for an unrelated reason so I'm sure it wasn't that. I pushed the car back into the spot and checked under the hood for anything obvious. Not knowing which cable was the CPS I wiggled as many as I could. After 15 minutes I tried again and she fired right up. The Sport light was still flashing.

Not wanting to tempt fate and try a restart I headed for home. The transmission was in limp-home mode and engaged only 3rd & 4th gears. Highway performance was normal. Once back in my garage I shut her off and back on again. The engine started fine, this time with no flashing Sport light. I took a lap around the neighborhood and everything was back to normal. I'll have my local mechanic change it. I know it's an easy job but it's too cold for me to lay on an unheated garage's floor. I'm due for a car inspection and oil change. The sensor mounts next to the oil filter so while the car is up on the lift he can change it easily.

I hope my snap diagnosis is correct but I'll be renewing my AAA membership just in case. One more thing. As I checked old posts for CPS info I found a reference to the Fuel Cap Alarm being related to the CPS. I have been seeing the FCA intermittently for at least 6 months. I can't say for sure but if you get the Fuel Cap Alarm it could be a warning sign of a future CPS failure.
http://www.cadillacforums.com/forum...m/51395-99-catera-fuel-cap-warning-light.html

UPDATE:

I wanted to put an ending to this story. I just finished an 900 mile weekend with my new Crankshaft Position Sensor and the engine never skipped a beat. It started every time. No stalling. No codes. Nothing. Thanks to the information here I was able to save myself the frustration of dealing with clueless service techs. I ordered the part, handed it to the service manager, they installed it, and that was that. I was a little nervous during the first 30 miles of test drives before the weekend trip but after that I stopped staring at the gauges. Except for the speeding ticket I got (81 in a 65 zone) it was an uneventful trip.

It just turned 68,000 miles this weekend. After rooting around the engine and tracing the CPS cable I don't think the sensor actually wears out. It's the cable itself that's the problem. It passes very close to the left hand exhaust pipe and the oil cooler lines. I think the heat damages the sheathing (either melts it or cracks it) and shorts the sensor leads. I forgot to ask for the old part so I don't know which. Even though the cable has heat shielding, the farther away from the those heat sources the better.

GM/ACDelco PN= 90494182
BOSCH PN= 0261210

Elvin

 
#33 ·
My 2001 sport just had similar symptoms, cranks but doesn't catch.
Took it to my local Caddie dealer, told them I wanted the CPS replaced and the cable rerouted.
CPS & cable cost (cdn)$ 76.95 and labor to install $204.00
Car is back to running brilliantly.....
Many thanks!
 
#35 ·
I'm not certain, but I don't think so. From what I understand - the CPS sensor detects one section of the crank shaft as it rotates. Each time this section rotates past the sensor, it sends a signal. So as you crank, the signal will go on and off. I'm not sure if your voltmeter will be quick enough to pick this up.

BUT... no reason not to give it a try. If you suspect thats the problem, you'll have to get to the connector anyway to change it - you might as well take 5 minutes to try this before you change it out.
 
#38 ·
Hey there.... I am going to replace the heater valve on my 01 and wonder if it would be a good time to also replace the crankshaft sensor at the same time, Mine is Ok car is fine, but I have been heariang so much about the sensor I feel it might be a precaution to replace it while I am under the hood

So where is it located and is it a hard job ( for a shade tree teck.) so someone please advise... thank you.... Lee ( need the info asap. thanks )again
 
#39 ·
This is an extremely well designed/built car from an engineering stand point. Most likely the German Opel side of Cadillac which did the building that you object to and or take issue with. Unfortunately most dealerships failed to train their employees as they do overseas to work on a Catera.
 
#40 ·
I have a 97, I feel they are a well built car, but of course you definitely have to take care of them (just as any vehicle). Unfortunately, I bought mine 4 years ago for $13,000, 3 months after purchase, oil pump failure caused a $8,000 (used) engine to be installed. They wanted $12,000 to (try) and rebuild the old (rediculous!). Once installed, has been great until a month ago. Same symptoms, running along nicely, then dies with no warning. Sit on the side of the road, let it cool, fires right up, drive until good operating temperature, dies again. Frustrating to say the least. I thought it may be some type of temperature sensor for the fan because it seemed to die just before (or maybe just exactly when) the fan was to turn on to cool.

Now that I see that others are having the same problem with the CPS, I will try that first. I will post my findings.

p.s. Does everyone else have the same issues with the Cadillac dealers?
You know, they don't seem to want to help you out with your Catera?
They almost look disgusted when you mention the name. And, what is worse, I find that GM should be ashamed of the rates associated with Cadillacs. Obviously they think that if you own a Cadillac, you must be made of money. I end up doing everything myself because I can not justify the costs they want to fix, or even guess what your problem is. Ok, i'm going, just getting angry again.
 
#41 ·
Another Cadillac repaird due to this post. My Catera went quick. It only hard started a couple times & then just quit starting. Something popped into my head that reminded me of this post. I re-read it & sure enough, that's what I was having. No amount of waiting or jiggling wires helped. Searched around & sure enough, O'Reilly auto parts was the only place that had it in stock locally & had the best price to boot ($39.99).

I suspect that I could have done this without removing the wipers & cowl, but it did make it much easier to see what was going on.

For those who aren't aware, the actual sensor is located just below the oil filter (under the car). This post is mostly dealing with where the connector end is (on top of the engine by the four vaccume hoses that exit the rear of the intake). If you were quick, I would say that it wouldn't take more than 1/2 an hour to 1 hour to do this. I just unsnapped the connector, unscrewed the sensor (make sure you have a torx socket) & pulled from the sensor end. The connector pulled all the way down with a few minor snaggs. Also, the "screws" under the rubber molding by the windshield aren't actually screws. You just need to turn them about 1/4 turn to loosen them in their hole. Be careful not to break them (4 of mine already were from the previous owner) because they are plastic.
 
#46 ·
After having the car sit for almost 9 months because I just couldn't look at it anymore (because it just wouldn't keep running once operating temp was reached). I decided to go out and purchase a CPS (Crankshaft Position Sensor), paid $110 CAD for it, they had lots in stock because they said it was a common problem. I took almost 4 hours from start to finish, but ya baby! It has been running, and running and running without a hitch now for the past month. When I pulled the old one out, the wires had been pinched in the heat shield, when it got too hot everything expanded and shorted the sensor, causing the car to shut down. Re-routed the new one around the problem area, and kaabam! Life is good again. Once I purchased the CPS, that is finally when I got some answers from the dealership on the problem, not before, go figure, if they figure you actually may know the problem already, they are willing to help, otherwise, they will let you squirm and pay big bucks on diagnostics!!! Not very nice I would say, would you?
 
#47 ·
Yeah, so after running beautifully for over a year, that damn CPS goes on me...A bullet that I though I was going to be able to dodge reared its ugly head. lol. I guess my suspension upgrade will have to be put on the back burner. So the Cat will be sitting for the next couple of days while I wait for GM to bring the part in $85 is not bad. I may try napa to see if I can get it sooner. So for anyone thats done this themselves. Is it easier to access the sensor from the side or sliding under from the front?
 
#53 ·
please Help I own a 99 catera ran great for 4 yrs but one day stopped at a store turned off when i cam out tried to start it back nada even when cold.. had a verry miner miss min. befor i stoped tho..ran ODB 2 on it last code was is Bank1 cyl. 1 Cam sensor error ..code right befor that was cyl 3 misfire..nada about the crank sensor tho.. have all ready had to replace valve cover gasgets $62.00 autozone not to hard...other mancanic said it would run with a bad cam sensor is this right???
it has fire at the plugs/coils and is getting gas injectors are working
He said it sounds like the intake mainafold Temp sensor Ty. with 98 up GM's sence i was getting fire at the coil pack's which the crank sensor controls the fire and gas. does it?
but it dident give that code..he said if it is way outa range it would make the timming to far advanced TO HOT or de advance TO cold to start. is this right?? could the intake Temp sensor advance the timming so far to cause the cam sensor make a code??? and the car not start at all..
The Cam sensor is 133.00 us please help..
:confused:
 
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