Poor fuel economy, sputtering and smoke

I recently changed my camshaft position sensor, crankshaft position sensor and lift pump to clear a few codes and get my 2004 beetle tdi running again. I replaced the Mass airflow sensor not long ago also. It's running but my mpgs are way down. I went from 42 to about 35-33 mpg. I noticed some smoke when shifting from 2nd to 3rd and the car sputters a bit before the smoke blows out. I cleaned a ton of gunk from my egr while I was tinkering. It was caked on really thick. I'm getting a Mass airflow sensor code (signal implausible) when coasting from highway speed to merge with traffic. I cleared the maf code and it comes back after a couple hundred miles or so despite my spraying it with maf sensor cleaner. I have a vcds lite and would be happy to post some measuring block data with a little guidance. All help and suggestions is appreciated, thank you!

You probably need to put a Bosch MAF in there. Or before that check to make sure the wiring leading to the MAF is good.

Did you check your torsion? What’s it set at?

My new Mass
airflow sensor is Bosch. Not sure what torsion value is or how to check it, LOL

I checked the mass air flow sensor wires with a multimeter. They checked okay , voltage within spec. I also read the measuring blocks and the pressure was within spec. Car also surges about 500 RPMs at idle sometimes. It goes up and down fairly quickly kind of jumping.
Torsion value -5cf, i just checked.
MAF actual at idle is 225 to 245 mg/str.

Before you go much further read this.


http://forums.tdiclub.com/showthread.php?t=336279&highlight=problem+setting+torsion


You should check your cam also. My cam torsion went to -4.something when my cam was going bad.

I read through a lot of the thread you suggested. I'm not sure how go check my cam to see if it's going bad. I didn't see any posts In that thread about sputtering or black smoke or jumping tach issues. I'll keep searching

Easiest way is pull the valve cover. This will require removing the upper intake hose and the egr. Very easy to do.

Once the cover is removed look at the cam lobes. FEEL the edges are they sharp. Each of those cam lobes has a chamfered edge that should be very smooth and should be visibly there. Rotate the engine by the crankshaft using a 19mm 12 point socket so that you can feel and see all of the cam lobes and their edges. Most of the wear occurs around the tips.

The cam and crank sensors you replaced were they Bosch also? I just recently saw a thread where a member put in a new crank sensor and didn’t tighten it down all the way, his car was running similar to yours. Are the wires to those sensors in good order?

I replaced the crankshaft position wire all the way to the ECU. It had a short I believe. The camshaft position wire tested good. I'm don't believe the new sensors are Bosch. I'll review my parts order to check

I think I may have a boost leak. Coming home from work Tuesday morning my intercooler pipe blew itself off of the EGR. It looks like when the hose popped off it dislodged a fuel line. I was able to reconnect the fuel line, no obvious damage. I have ordered a doggie collar fix kit to prevent this from happening again because I noticed significant wear on the hose tabs. I am hopeful that this will fix my issues with the sputtering, smoke and fuel economy. I am hopeful but trying to keep my expectations low.

Common problem on these PD engines with those clips holding the boost pipes. I have a dog collar on mine.

A boost leak will cause smoke and other issues, hopefully this will fix your problem. Also it might be a good idea to check the rest of the boost pipes make sure all the connections are fully seated. Behind the passanger side front tire is where several joints are.

I got my dog collar fix put on and I'm still having the same issues. I'm thinking about pulling and cleaning my intake manifold, looks like quite a job but I'm sure it's clogged, my egr was caked up bad so I'm sure the intake is in the same shape. I thought about buying a used one to minimize my downtime but I'm not sure which one I need. My engine is bew I'm pretty sure but the pics of the alh intake look more similar. Where is a good place to get an intake?