Will not start. Recently had a head gasket leak. (Water into cyl #2)Got it all back together and running fine. Drove it Tuesday and ran perfectly, parked in dreveway. Wednesday morning it would not start. Turns over but gives no signs of starting. Checked for fuel pump operation and i hear the pump starting for a few seconds as expected. Checked for engine codes and found: P01313, P1316, P0102(MAF sensor flow low),P0105(manifold absolute pressure low),P0112( air intake temp low)(it's been over 80 deg F here),P0117,P0400(EGR),P1000,P1111. I believe the P1313and P1316 are left over from the head gasket leak.(Cyl #2 misfire)P0117 is because I had a loose connector on the temperature switch on Tuesday. I don't know the reasons for any of the others.

I replaced the MAF sensor and had the throttle body professionally bebuilt last year. I also replaced both fuel pumps last year. I followed instructions for resetting the imobilizer and the inertia switch just in case. No go. Any ideas?

 

Was it started for a short period of time, then shut off?

 

No, I drove it into the driveway one evening and shut it off. The next morning it did not it nothing but turn over. No indication that it tried to start. Just the starter turning the engine with no signs of life.

 

So, I might have a look at the CKPS to see if it was still plugged in, and correctly seated. Check for fuel pressure. Check for spark and injector firing (noid light, scope, test light?). Then go from there. Make sure the en gine harness plugs are ll plugged in. How about the cam sensor plugs?

 

CKPS... is that crank position sensor? How do I check for spark? Injector function?

 

Yes, the one down at the bottom of the bell housing. A "noid light", available from Amazon or Harbor Freight, or an LED in series with a 5k resistor can tell if the injectors are firing- You have to get either connected in parallel with the injector coil.
or

http://www.harborfreight.com/11-piec...set-97959.html

You can pull the coil and lay it on top of the valve cover with a plug hooked to it, with a ground wire to the plug "case" will let you see it spark.

Some part of the answer to your problem is model dependent. It is a good idea to add the car MY to your signature or mention it in the post1

 

OK, thanks. I'll check these things. It's a 2000 XJR 110K miles.

 

I found a noid light set (loaner) at the local auto parts store. (Auto Zone) I tested the wiring to two of the injectors and they are firing. I also pulled one coil and tested for spark. Yep. Still doesn't start. I haven't been under the car yet to look at the crank position sensor.

 

Looked at the crank position sensor. From outward appearances it looks fine. In place and plugged in and wiring intact. I checked the fuel pressure at the fuel rail and have 42 psi. Any other ideas?

 

Hi ppauto,

You can only tell so much by visually inspecting the CKPS, but since you have spark I think we can, at the very least, assume that the CKPS has not completely failed (although it could be failing).

You've confirmed that at least two injectors are receiving electrical pulses to fire. Have you confirmed that fuel under pressure is available at the fuel rail?

You've had a LOT of codes - have you cleared them to see which ones reappear?

Don

 

I decided to check the compression. Drivers side all good. The passenger side, 0 compression all 4 cylinders. I pulled the valve cover expecting to find broken chain/tensioners, parts, etc. Everything appears normal except the cam flats don't line up. It looks like the exhaust cam jumped one tooth. This engine had upgraded tensioners installed under warranty years ago. (the second generation spring loaded type)How could the secondary chain slip a tooth with the tensioner in place and still maintaining the chain tight?

 

Sounds like you are on the right track. My only fear would be if you have cylinder
damage due to overheating. The cylinders with Nikasail don't tolerate overheating.
It damages the coating and then you won't get compression. I hope adjusting the
chain and camshaft corrects the compression. Certainly try that first. A little oil in
each cylinder with low compression will temporarily correct a compression leak. Maybe look at "Cylinder Wash" comments. If you determine that the engine is beyond
economical repair, consider a used XKR engine. They usually have fewer miles.

 

So, is there any chance that the cam slipped enough to cause the loss of compression but not far enough to damage the valves?

 

It sounds like you slipped two teeth and bent the valves. The second gen tensioners can still crack and lose pressure, but thought the springs were supposed to prevent the chain skipping.

 

So, anyone want to buy an XJR cheap?

 

As to your question about chain tensioners and cam slipping... you also "mentioned" head gasket on Cylinder 2 side. So, it sounds like the head that had the new head gasket has now come up with slipped cam timing. I would say something bad happened in the head gasket work!

 

I know it looks that way. I did the work myself. The mechanics is my thing. The electronics is not my thing. I had no trouble tearing it down and putting it back together. I did it all by the book. I have been driving it for 2 weeks and it has run perfectly until the morning when it would not start. I parked it in the evening after an non eventful drive. The next morning, it would turn over but not start. There were no unusual noises while driving or when attempting to start in the morning. This is why the cam positioning issue is a mystery to me. The timing chains were intact and the secondary tensioner was maintaining tension on the chain. I don't see how the cam could have "slipped". I checked the position and it was actually 3 teeth off. I don't see any damage to the chains or cam gears. I reset the cams to the proper position and turned the engine by hand. It binds up. There is definitely valve to piston interference. (bent valves)

 

Hmmh...

So that pretty much means the teeth jumped OR the front sprocket came loose. Did you re-time it, or just get the teeth set up like they were originally? Anyway, you can get an engine for about $2,000 or $2,500. or just fix buy a head or fix the valves.

Nothing sucks like getting it all back together and having another problem. But, they run so good when they are right! I suggest you think things over before making a quick decision.

 

I re-timed it with the timing tool set. If the front sprocket came loose, the cams would be out of time with the crank but not with each other.

 

If one of the sprockets came loose, it's timing would be different to the other cam in the head and to the crankshaft. The sprocket relationship to each other would stay the same but the cam would slip on the shaft themselves as it tries to open the valves against the resistance of the springs. So, technically, the chain didn't jump the sprocket but the timing is still affected....