Replaced timing chain guides on 540i. Rolls over but won't fire.

[Cowborg]

Hi,
Recently I replaced my timing chain guides and tensioner because they were broken. We rented the camshaft positioning kit and followed the instructions exactly while reassembling it and getting the timing correct. After we got the car back together, we go to start it out. It rolled over and fired for a split second then shut off. Now it rolls over but won't fire at all. I hooked up the fault code reader and was getting these 2 fault codes.

Table 0F
71 - Camshaft Position Sensor cylinder 1-4
72 - camshaft Position Sensor cylinder 5-8

My father thinks it's not getting gas. What could the issue be and how do I go about fixing it? A friend of mine told me that the fuel lines may possibly need bleeding but he hasn't taken a look at it, he just went by what I described to him.

[Silverlight]

It's probably because your upper timing cover is not in the correct position if that's the only codes your getting. The camshaft position sensors are really sensitive to their location

[edjack]

Good point. BMW has a Special Tool to position the upper covers.

[rf900rkw]

How can position set a circuit code? And keep in mind that Peter drove his car for many months after the shop missed the cover position by as much as possible.

OP step one is to check all your wire connections. More than one person has crossed up a few wires, since all the plugs are the same.

[Silverlight]

I figured that if the sensor was in the wrong location then it would be picking up inaccurate values setting the code. I may have read that has happened somewhere on bimmerforums before, but I'm no expert. Just curious, but did peter receive a code while driving with the upper timing cover out of position?

But on the other note, yes always check wires before hand. I myself have mixed up/forgot to plug wires back in after finishing something. Things like that would really stump me sometimes hahah

[cwise12]

Correct me if I'm wrong here, but I believe that the sensors being off by a bit won't keep the engine from running... just keep the VANOS from functioning. I would think it would be a spark or fuel problem.

[Cowborg]

Out of curiosity we stuck a screwdriver into the sensor holes to see if anything was blocking it. Well the vanos control unit (the circle with all the cut outs, not quite sure what it's called) was loose and just wobbling around. I guess the instructions that said to tighten them to 40n/m was a bit off. So now they are tightened and we're putting everything back... again. Then we'll see what happens.

[pegcity]

fingers crossed

[edjack]

There's a remote possibility that disturbing the sensors killed them.

Check for spark: Remove a plug, ground it to the engine, and spin the engine over. If no spark, consider replacing the sensors with OEM parts.

Have you measured fuel pressure, too? S/b 50 psi+. There s/b a Schrader valve on the fuel rail for this purpose.

[Ballard540]

^+1

Did a 540 a year ago, hooked em back up and driver sensor was dead. But ran when pulled into the shop.

And these are circuit malfunction codes, not correlation codes. They are probably bad

[rf900rkw]

If the trigger wheels weren't turning, or not turning the same speed as the cam, it can set these codes.

[Cowborg]

IT LIVES! Running just as fine as it was before this problem developed. There is a slight diesely sound to (very slight) it but I've read that some people just develop it with no issues. Lessons I've learned from this:

- Write down or take pictures of the steps so it's easier to put it back together
- Have a space that you can work in any weather (snow and rain made this take forever)
- Do lots of research from as many sources as possible
- Have a huge breaker bar

So thanks to everyone who helped on this thread and the other thread I had!

[Ballard540]

What was the issue? And besian systems has a solution for the diesel noise if you ever want to fix it

Sent from my DROID RAZR using Tapatalk 4 Beta

[Cowborg]

The vanos disc things were loose and just rattling around. I guess the instructions to tighten them to 40 n/m wasn't quite tight enough.

I'll have to look into that. It's not bothering me too much yet but I'm just happy to get it back on the road.

[Silverlight]

Glad to hear you fixed it! Timing chain guides are a pretty good diy accomplishment if i say so myself. Can't wait to tackle them as well as reviving the vanos system!

[Cowborg]

Thanks! The first big project I've done besides changing the clutch in my truck but this was a "bit" bigger of a deal than that. Probably would have enjoyed more if the weather co operated but oh well :p

[pnottus]

It's probably because your upper timing cover is not in the correct position if that's the only codes your getting. The camshaft position sensors are really sensitive to their location

Wow, best answer i've found. You might have saved me from tearing all down again. Thanks