Hi everybody,

My '96 2.3L died the other day while driving. The timing belt had snapped, so I replaced it. Everything was working fine prior to the belt snapping, but now that the belt has been replaced, it just cranks with an occasional but predictable "whoomph" noise (exhaust?).

I have confirmed I have spark, fuel, and air within specs, so the fundamentals are in place. I checked the crank position sensor, and cleaned the "sensing" end with my finger (it was noticeably dirty), and it looks good. Cam position sensor...it's there, and the wires are connected, but I can't say otherwise. Belt tensioner is sound, all fuses are good, and so far as I know, so are all the relays (no signs of electrical distress). I took the plugs out yesterday (replacing today), and they were wet with fuel (likely from all the cranking in the last few days), but still...just in case that's a clue. The AC, steering pump, fan, thermostat enclosure, and radiator hose have not been replaced just yet, but I didn't think they were necessary before attempting a dry start; however, all necessary sensors are plugged in, and the MAF/air intake stuff is plugged in also. Please correct me if I'm wrong about the other stuff needing to be reinstalled.

The engine has 200,000, so anything is possible in the "coincidental failure" department, but again, it was running like a top when the belt snapped. The only notable is that I had a P0420 code, and a cont. memory code of P0340 when I scanned it shortly after it broke; however, my check engine light had been on for about 3 weeks, so either or both codes were present before the belt broke.

I've read, and read again that this is typically a timing case. I'll double-check today that I've got the crank/#1 cylinder at TDC on the compression stroke, and do the same to ensure the cam sprocket marks are "perfectly" aligned with one another, but I've been having an issue with the cam marks lining up perfectly. Instead of lining up perfectly across from one another, they end up about 1/2 tooth off from one another when the belt is fed around it properly. I was either given the wrong belt at the parts store, or my marks are manufactured ever so slightly off. Even so, 1/2 tooth of misalignment on the cam shaft should result in poor performance versus not starting....right? I've also read where some cam sprockets have two marks. I didn't notice a second on mine, but I'll check again, and make sure I have them matched accordingly. Also, I cannot find the mark on the aux/oil pump sprocket, but in a thread where another had the same issue, it appears that one can get pretty close by placing the factory "dent" that's on the edge of the sprocket at about 11:00. I'll certainly listen to any suggestion that can tell me how to properly align the oil pump sprocket without a mark. Given the cam position sensor takes its readings off this somehow, it might be playing a role in my problem.

Also, some other tidbits:

Will the cam position sensor prevent the engine from starting if all other things are in working order? I had that cont. memory 0340 code, and while it was running prior to the belt snapping, perhaps it's playing a part now if it failed somehow.

I read a forum thread on some Ranger site somewhere indicating the rear O2 sensor can play a role in "tricking" the PCM into thinking the cam position sensor isn't working. Anybody else hear anything similar? My other code (P0420) is consistent with the rear O2 possibly needing attention.

I had one person I spoke to who said I likely damaged the crank position sensor when I loosened the pulley/damper. It's the all-in-one pulley/damper type, so a harmonic puller wouldn't work, and a puller large enough to grab from behind would be a squeeze. Instead I put a 2x4 on the top of the damper, and "tapped" it with a hammer, rotated, and repeated until it loosened a little (and it barely wiggled at all (literally, almost indiscernible). I took care when sliding it off too. I find this person's claim a bit unlikely since I've read stories of the pulley/damper being loose and wearing out the keyway, and not causing issues with the crank sensor. Still...any input is requested. Again, I've seen the sensor, and it looks quite nice actually.

I also read another thread on some site (this one?) where the damper's timing pointer/line has to be on 10 degrees BTDC on the cover when the crank keyway is at 12:00. Mine centers on the TC notch of the cover when I'm at 12:00.

Is there anything else I might look into if the problem persists beyond what I discuss above? It just seems odd that an engine can be working one second prior to a timing belt snapping, and not the second after it is replaced.

Any suggestions, hints, tips, tricks, or offers of help will be greatly appreciated. Something is either wrong with my reassembly, or there was a "secondary" failure along with the belt failure...or both. Help desperately needed.

Dave

HOLY LONG POST BATMAN!

I think you may have read one or more of my recent timing-related posts.

Based on what you've said:

Go get a cam position sensor right now, just do it.
The computer takes the crank position sensor FIRST (the truck won't crank without the crank sensor connected but WILL crank with cam sensor disconected) uses the cam sensor to make sure they match for fuel timing/etc. so YES it could be making your life harder right now.

Sounds like a timing issue FOR SURE
I actually counted how many teeth we're between 12 o'clock and where the 3 pulleys point in another thread. Sounds like you read that.

KEEP TRYING. I set my timing literally 30 times. I'm not even kidding. l thought there is no WAY it'll line up this far off/far from where it says it should be. And voila it ran perfect.

__________________
'83 Ford Ranger 2.3L 4Spd, Dual Tanks, 195/60R15's, Welded Rear End TOTALLED AT 483,211 MILES

Yeah, I figured I'd cover all the bases with a long post initially, and avoid a long series of responses and suggestions up front.

The problem ended up being that I have 2 marks on my cam sprocket (and most procedures do NOT mention this as a possibility). As I wasn't looking for a second one, I didn't look for a "matching" shape (i.e. diamond-to-diamond, triangle-to-triangle), but instead went with the first one I found, not knowing there could be a second. When I read somewhere that some models/engines have 2 marks, and that the shape must be matched, I looked and found a second one. As luck (or lack thereof) would have it, the one I was using was a diamond, and the cover mark was a triangle. The second (i.e. correct) mark on the cam sprocket was 60 degrees off the one I was using, so the result was obvious.

I also noted from a previous thread somewhere, wherein there was no mark on the oil pump sprocket, which was also the case with me. In that thread it was noted that the factory "dent" on the edge of the sprocket would be close to 11:00 when properly lined up, so that's what I did with mine. Upon further inspection, I finally found the faintest of marks on my oil pump sprocket, and it was indeed at 12:00 when that "dent" was at 11:00. Coincidentally, when I properly lined up my cam sprocket, the cam sprocket's "dent" was also at 11:00. Might be helpful for somebody else should they find they cannot find their mark on either the oil pump sprocket, or the cam sprocket, though I don't know if that's by design or coincidental.

In any event, my engine is running fine now except for a slight off-idle hesitation once the engine is warm/run for a couple of minutes. That's for another thread.

Thanks for your response though! I was beginning to believe nobody cared!

Dave

Glad it's running! GOod work

__________________
'83 Ford Ranger 2.3L 4Spd, Dual Tanks, 195/60R15's, Welded Rear End TOTALLED AT 483,211 MILES