"weak" crank after head swap, won't start

dislexicmofo

Veteran Member
Joined
Feb 9, 2008
Location
Atlanta, GA
TDI
2003 VW Golf TDI GLS
First, I have read Whitebreads "so your car wont start thread". It was helpful but I am running out of things to trace.

The background: I put a new head on the car, timing checks out, I can rotate it by hand still and feel good compression and the release of said compression, checked several times while doing the belt. I do not believe that it is anything mechanical.

Symptoms: When cranking it seems to be "weak", it turns over, but not as readily or as fast as it should. It is hard to describe, I may post up audio tonight.

I was actually having problems with this before the TB failure so this may be leftover. The full story on that is that it was having trouble starting for a few months, you could hear the gear engage but I think it was sticking because it would grind a bit after starting, and then it would not start one day. I pulled the starter in the parking lot and put in a new one and it still wouldn't start. You could hear the starter engage, but then no dice. So I pulled it and took it back, they tested it, said it was fine, I put it back in and it started right up. (I am giving this information is just to paint a complete picture.)

What I have already done:
All the battery cables check out. battery to starter, ground cable, ground strap on starter, all are 0.4 ohms or less, which should be fine.
The battery is good, I had it checked and then charged it all the way with my fancy new charger/starter (great deal at harbor freight right now, $65 for 200 amp assist, 40 amp charge), the problem persisted. (It should be noted that the car behaves as described even if jump started.)
I think that the starter is good, It engages and turns over. I replaced it less than a year ago with a cheap o'rielly part as described. I know this is not ideal but it is what I did. I will be exchanging it later today to be safe, in case they gave me a bad one.
I have primed the filter, lines, and pump with a mighty vac, three times as instructed in the previously mentioned thread. I get good fuel form all of the lines so there is not much air left in there. I don't get as much fuel out of the hard lines as I would expect, I have not had to do this since I ran it out of gas 3 or four years a go so I don't really remember what to expect when the engine is operating properly.

If the starter doesn't fix this does anyone have any ideas on where to go next?

I also want to say thanks to everyone that's helped. I bit off more than I thought I could chew but with the help everyone has provided I have made it this far! I don't want to end up towing it to someone this close... I can taste it!
 
Last edited:

BobnOH

not-a-mechanic
Joined
May 29, 2004
Location
central Ohio
TDI
New Beetle 2003 manual
remote possibility it could be the IP case relief valve. Also, you do need to crack the injectors to finish purging the fuel supply
 

tditom

Top Post Dawg
Joined
Sep 5, 2001
Location
Jackson, MI
TDI
formerly: 2001 Golf GL, '97 Passat (RIP) '98 NB, '05 B5 sedan
...Symptoms: When cranking it seems to be "weak", it turns over, but not as readily or as fast as it should. It is hard to describe, I may post up audio tonight.

I was actually having problems with this before the TB failure so this may be leftover. The full story on that is that it was having trouble starting for a few months, you could hear the gear engage but I think it was sticking because it would grind a bit after starting, and then it would not start one day. I pulled the starter in the parking lot and put in a new one and it still wouldn't start. You could hear the starter engage, but then no dice. So I pulled it and took it back, they tested it, said it was fine, I put it back in and it started right up. (I am giving this information is just to paint a complete picture.)

What I have already done:
All the battery cables check out. battery to starter, ground cable, ground strap on starter, all are 0.4 ohms or less, which should be fine.
The battery is good, I had it checked and then charged it all the way with my fancy new charger/starter (great deal at harbor freight right now, $65 for 200 amp assist, 40 amp charge), the problem persisted. (It should be noted that the car behaves as described even if jump started.)
I think that the starter is good, It engages and turns over. I replaced it less than a year ago with a cheap o'rielly part as described. I know this is not ideal but it is what I did. I will be exchanging it later today to be safe, in case they gave me a bad one...
Cheap starters are not so cheap when you spend hours and hours troubleshooting and replacing them ;). Also note that when they "test" the starters at most parts stores they are not testing them under a load- only checking to see if the pinion spins out and turns with 12V applied.

Hopefully you will get a good one this time. Same thing happened to us a couple months ago on my s-i-l's NB.
 

dislexicmofo

Veteran Member
Joined
Feb 9, 2008
Location
Atlanta, GA
TDI
2003 VW Golf TDI GLS
Yeah, in hindsight I would have gotten a Bosch unit, but I couldn't get one that day. And I thought about the load testing too, I'm simply not going to take no for an answer.

Bob, I cracked the lines and got fuel earlier. It wasn't spraying everywhere though, just a little bit came out, I assumed that was enough. How many cranks on a cracked line should it take to bleed them?
 

BobnOH

not-a-mechanic
Joined
May 29, 2004
Location
central Ohio
TDI
New Beetle 2003 manual
Yeah, in hindsight I would have gotten a Bosch unit, but I couldn't get one that day. And I thought about the load testing too, I'm simply not going to take no for an answer.
Bob, I cracked the lines and got fuel earlier. It wasn't spraying everywhere though, just a little bit came out, I assumed that was enough. How many cranks on a cracked line should it take to bleed them?
if the pump is purged, it just takes a few cranks to spray out all 4
 

dislexicmofo

Veteran Member
Joined
Feb 9, 2008
Location
Atlanta, GA
TDI
2003 VW Golf TDI GLS
what kind of "spray" are we looking for here? to the hood? bubbling up a little around the joint... somewhere in between?
 
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