00 cranks but wont start

Hello everyone. I'm in a bit of a tight spot and could really use some help.

I have a 2000 XJ that I just put a re manufactured 4.0 into. I tried to start it today and it will not start. I ended up putting a new CPS and cam position sensor in.

When the CPS is unhooked it will just crank like it wants to start but nothing happens. When the CPS is plugged in it will backfire through the intake and kind of bog down and the dash lights dim. There is no "no bus" in the odometer.

I didn't align the cam position sensor at first, but when I realized that I needed to I set #1 to tdc and put the shaft back into the oil pump. Here is where I had to get a new sensor because I forgot to take out the allen wrench that I used to align the sensor and shaft :gonnablow But the top of the shaft spins freely and doesn't interfere with the cam sensor so I think it is still good...

The battery was only reading 10 volts but even hooked up to a charger it wouldn't start. I am getting spark and fuel. All the sensors and grounds are hooked up that I can see.

Could something be mechanically wrong with the timing parts inside the engine? Do I need to adjust my TDC some since it was approximate when I set it? I can't find a mark on the damper pully to match up with the timing marks on the timing cover. Do I need to set base timing somehow?

Thanks for any help.

Just regarding the voltage,

Were you just connecting a charger to add to the 10 volt battery and trying to crank it? The charger will not give you the current you need to supplement a weak battery. The battery needs to be fully charged (several hours on the charger) or you need to use a high current device designed for jump starting, not a simple 2A or 2/10 charger.

Sounds like you need to search how to set the cam sensor timing. There are links to good write-ups on that.

And charge up the battery better.

It was a charger/jump start set up that was set to start. I think it was 200 amps. Is that not enough? It just made the engine crank faster.

I did realize that I needed to set TDC and set the cam sensor and I did that but it still wont start. I even had my dad crank the Jeep while I moved the sensor a little to find the sweet spot.

Here is a video of it trying to start. That was on the 12v/40 amp setting of the charger after it had been charging for a while. We tried on the 200 amp setting after that and the same thing happened.
http://www.youtube.com/watch?v=R30Gej9szXI

-Pull battery and take to parts store and get it Load Tested.

the electronics quit working around 10-11 volts, it still cranking over BUT No Workie.

Use a test multimeter to read batt volts at the batt terminals (>12 V), also while cranking (>11 v).

1. As said, pull the battery, fully charge it, then have it load tested. Think of a bad battery like the Grand Canyon and your charger like you trying to "P" it full--ain't going to happen.

2. NO BUS and won't start usually indicates an internally shorted crank sensor on the late models. If this is your problem your gauges won't show up when the NO BUS is present. To confirm, unplug the crank sensor then turn on the ignition switch--if the gauge miraculously reappear then your crank sensor is for sure shorted out.

So this is a reman engine that has never run?

It is possible that the camshaft itself was not timed properly, and that would cause the issues you're describing.

Check with a good battery first. I've replaced the entire distributor housing on my 2000 and never had to mess with any timing, afaik the computer takes care of the timing.

battery is not causing issue. have jumped numerous dead vehicles. so its not the battery. very possible cam crank sensor issue. the computer sets timing but there should be tdc marks next to the water pump. improperly installed cam shaft would not cause it. possible pinched harness/wire somewhere? either that or bad cam/crank sensor

Your cam sensor is still not properly aligned or worse-case scenario, as bourbon said, the timing set wasn't set correctly, so the physical cam timing is off(you have to pull hb and timing cover off). You had the coil rail off, #1 plug out, and had someone put their finger over the #1 hole while you cranked it clockwise to 0* and they felt air pushing out? You might have to spin another 360* to get to the end of the compression stroke instead of the end of the exhaust stroke if air didn't come out. Read this:
http://motorage.search-autoparts.co...estandard//motorage/292005/169830/article.pdf

oops, guess i should read things better. would defenitely make sure cam is in time with crank and there should be a mark on the damper somewhere. one way to check is to pull valve cover and watch #1 valves/rockers for no load on exhuast or intake. pull the plug and check where piston is. but the best way is to just pull the front timing cover and make sure the cam gear dot is matched up with the crank gear dot. if thats in time then you "distributor," cam sensor is not quite in time yet.

Thanks for the input everyone. I have classes down in Atl and the Jeep is in Chattanooga, so its not easy to work on it during the week. It is a reman engine that has never run. It no longer backfires through the intake and sometimes it will almost start, and then just go back to cranking.

I have pulled and timed the cam position sensor several times using the finger trick and a friend watched the valves while I turned the crank. The sensor has also been rotated while the engine was cranked to see if a sweet spot could be found. I can't find a timing mark on the harmonic balancer. I used a toothpick to align the sensor with the shaft.

It has a brand new battery (the other one was my dads, and the old battery was old/incorrect size).

I pulled the engine harness out today and looked over the entire thing and only found one cut wire going to the rear O2 sensor. Some of the harness sections were pretty stiff and the plastic coating was stuck together, but it all looked ok to me.

I also got a test gauge for the fuel pressure, it is at 39 psi.

Tomorrow I'm gonna try to get it to a shop. If the cam was installed incorrectly, the warranty covers the work for that since it would be a manufacturing defect. Unless you guys have something else I can check?

I also noticed fuel in my oil... Is that from the new rings not sealing yet and unburnt fuel getting past after I crank it?

Well, I have had it taken to a jeep dealership that was close by and they are taking their sweet ass time getting around to it. Today they finally told me that they got a p0000 code and no cam position sensor signal at the pcm. They said I need a new pcm, but thats wayyyyy expensive, $800 something for the pcm/install/program. Does that sound plausible to you guys or are they just throwing some expensive fix at me?

You said you had fuel and spark. If they're at the proper time, and if you have compression, it will run. Since you said you have fuel in the crankcase oil, I've a theory that you've washed the cylinder walls with fuel and are now suffering from a lack of compression. I've seen it happen with flooded engines.

Try putting a little oil in the cylinders through the spark plug hole...it will boost your compression. Just might work!

Thanks flyfisher. I'll talk to the dealership and ask them to try that. I just called and of course the guy working on it is gone and there is nothing useful written in the paperwork about any compression testing they might have done. GAH! This is the first time I have ever had to take a vehicle to a dealership/shop and its a PITA...

Yea, I wouldn't bother asking a dealership or shop to put oil in your cylinders. I've run into a bad computer once before, it was easy to check for me because I have several XJs. 800 for a replace and...program? I don't understand why. There's nothing to program. It's literally 3 screws, 3 plugs and go.

Why did you replace the engine? Was it running before you replaced it?

I don't know why they would have to program one. I don't plan on them doing it. I think I'm gonna have it taken somewhere else where I can park it temporarily and try the oil idea and put in a "new" pcm if needed.

The other engine over heated and cracked the head and it was knocking/rattling really bad from the block after I replaced the head.

Does the pcm part number have to match exactly or will it work as long as its for a 00/01 AT 4.0?

nismochasse said:

I don't know why they would have to program one. I don't plan on them doing it. I think I'm gonna have it taken somewhere else where I can park it temporarily and try the oil idea and put in a "new" pcm if needed.

The other engine over heated and cracked the head and it was knocking/rattling really bad from the block after I replaced the head.

Click to expand...

So the PCM was working before you replaced the engine.

Yes another PCM should work. I've even run a 4cyl on a 6cyl pcm just to see if the pcm was what was bad. It ran poorly, but it ran enough for me to know I had a bad pcm.