Here is what I know: I was driving the car when the engine suddenly lost power and then shut off. Now it cranks, but won't fire or start.
- Fuel pump works, and I have pressure at least to the rail. Wet and gas smell in cylinder when plugs are removed. Starting fuild does not help.
- I am getting spark at the plugs.
-Timing belt is not broke, but appears to be looser than I expected. It moves the cam gear and rotor in the distributor when I turn it over, or crank by hand. (Maybe I have jumped a tooth?)
-I am now getting a CEL code 4, (CKP sensor). I'm not sure if this means the sensor or circuit is bad, or the computer doesn't like the sensor is reading.
-I rotating the engine by hand to find TDC #1, and there are two things: Eye balling the rotor position in the distributor, it looks to me to be off by a 1/4" rotation at least from making contact with #1 wire and TDC (maybe thats just me), but also right when I get to TDC #1 by hand, with the spark plug out, the crank very hard to turn until I push real hard and then it's easy until I get back around again.

Thanks so much

 

I suspect the CKP fault is cause of no-start. This can be a faulty sensor, wiring, connector, or ECU fault.

First check sensor resistance at distributor connector. If zero resistance or open, the sensor is the problem. If it's about 750 ohms (check emanual from DIY forum, Online Manuals for spec), the sensor is good and fault lies w/ other components. New or used distributor required to fix sensor fault.

Next step if sensor is good is to disconnect ECM/harness connector w/ CKP wires (there are 3 connectors, see emanual). Check resistance again between wires at harness connector.

If resistance is good, the ECU is problem (replace w/ used). If resistance is open/closed, fault lies in an intermediate wire or connector.

good luck

 

According to my Haynes Manual, it says on the 96 and new cars the sensor is near the oil pump and must be checked with a scanner tool. Can I still check the resistance at the distributor as you have suggested? I am planning to change the timing belt also, so I may find that the timing is off, and I'll have access to the sensor, since it is under the timing belt cover.

Also, what do you think about the tight spot as I rotate the engine by hand? When I say "tight," I mean it practically lifts the engine slighty before breaking free and continuing around. Do you think this means a valve is bent? or something else bent? Like I said, this is right at the very instant before TDC on #1 cylinder, with the spark plug out. I have a dowel in the cylinder so I can watch the piston move.

Thanks

 

Yes, you can check the CKP sensor as described, but need to find the connector that leads to sensor.

I see no reason to suspect broken timing belt. Your description of loose is correct, belt should be able to twist 90 degrees in tightest position. You could check engine compressions to rule out a bent valve.

good luck

 

I think he's correct about the CKP sensor being located at the crankshaft pulley for 96+. The wire for the combined CKP & TDC sensor comes out near the bottom of the lower timing cover and there's a connector alongside the back edge of the lower cover.

 

Update: The ECM checked out fine, and the wires up to the sensor plug are okay. The sensor seems to have no resistance (my meter seems to be acting weird). Anyway, I took the timing cover off, and my timing balancing belt is broke. Is my engine toast? The timing belt itself is not broke, but it is loose, and when I have the timing mark up, the #1 piston is not exactly all the way up. It is about 4 or 5 teeth off. I assume it should also be all the way up.

 

Cam timing off by a couple teeth might not have bent any valves. Unless it's been moving all over and it was at one time far more than 4 teeth off.

You know how to read the timing marks? The arrow on the camshaft sprocket it only approximate. The REAL timing marks are little dimples out at the teeth of that sprocket. They line up with the top of the head, or the top of the timing shroud behind the sprocket. The arrow is only to tell you whether you have to cam 180-degrees out.

 

Yes, I know what you mean by the dimples. I got the crank pulley off today (good thing I had the holder tool from amazon) and removed the lower timing belt cover. The plastic on the CKP was broke off on one side, which may be why it is throwing the code? But the crank gear timing marks are at the 9 o'clock position when the cam gear is at the TDC marks. Somehow the timing belt is so loose, I can slide it off by hand if I wanted to. I'm guessing it jumped teeth until it was too out of time to run? Perhaps it also jumped while it was turning it over to troubleshoot fuel and spark last week. Anyway, if I want to try to put it back in time and try to run it, I'm not sure what I should move. I understand how to tell if the cam gear is 180 out. is it possible to have the crank gear 180 out? Judging by the piston position, I think if I took the timing belt off and turned the crank clockwise 1/4 turn it would be at TDC and the marks would be lined up on the cam and crank. I know you are supposed to only turn the engine counter-clockwise though. I'm guessing this is not that simple...

 

The crank spins two times for every one spin of the cam. So only cam can really be 180 out of time.

The one way to ensure you don't hit the valves with the piston is to remove the spark plugs, rocker arms, and cam shaft. This will ensure that all valves are closed. Then get the crank to TDC. Then install the cam at TDC.

I remember JimBlake talking about having the crank 1/8th of a turn before the crank reaches TDC. Count the teeth on the sprocket, divide by 8, then use that tooth with the mark on the engine block. That puts all the pistons in the middle of the cylinder. Remove the timing belt. Set the CAM to TDC. Then move the crank to TDC.

 

Okay thanks. It might be a day or two before I get a chance to work on it again. I might get a hold of a compression tester too. We'll see what happens.