Engine RPM limited

FraggyTDI

Veteran Member
Joined
Jun 28, 2011
Location
Paynesville, MN
TDI
04 Jetta
Hello All,

I not to long ago completed a BHW/manual swap into a golf with a gtb turbo. I ran great for a few months until I lost oil pressure and spun a rod bearing. So over the last month I've rebuild the engine with new crank, bearings, oil pump, and main studs. So to get to my current issue, I've been trying for the last 2 weeks to get the car to rev higher then 1500 rpm. No codes are popping up. Engine acts as if it's hitting a rev limiter.

Here is what I've done so far:
Removed intake system and ran straight off manifold. No change
Decoupled exhaust no change
Did both intake and exhaust no change
replaced cam position sensor. No change
Reloaded engine map no change
unplugged and re plugged entire harness no change
Adjusted torsion values no change
Checked timing wheel on crank to verify it's correct and in same location. It is
unplugged vacuum to turbo to run wide open. No change
Today I installed new crank position sensor...I got a change I now can rev to 2500. I took a log doing a slow rev see link
https://log.malonetuning.com/chart/235498#H8KLCADDqzVJWwIDbcKNw40Ow4IgEMKEw5%2FChcOzwpAUwq1%2Fw4%2FDksO0wrDDikpJwrA0wrDCmMOqw5Nbw5rDhHjDsMK4M8OffMObdcOqFh9XP8KydinClikrND1qGGLDsm9eTijDhyMnElZbMz45wonClsKoZ03Cs8KvwottM3jDi8OawpJQZsKpw6EewpIKw5fChsKsw5XCry%2FCrMKSd8KDwqzCssKFw7wpwroGBjvCtDjDoMKIE8OOwrjDgCxmZVbClsKKw4Q8BcK%2FwrpNw7vDv8Ojwp1Cw6bCvsO%2FAMKpw7krOMOXAAAA

So this is where I sit with no idea on what to do next. To me it seems like an electical/mapping issue. Car ran perfectly normal the first time I installed it. All work I did was mechanical so shouldn't have an effect.

Any input would be greatly appreciated.

Thanks
Chadwick
 

miningman

Veteran Member
Joined
Sep 3, 2007
Location
alberta
TDI
2003 Golf
hate to suggest it ,but this is the same symptoms I suffered when timing belt skipped a few notches. Check your timing
 

FraggyTDI

Veteran Member
Joined
Jun 28, 2011
Location
Paynesville, MN
TDI
04 Jetta
hate to suggest it ,but this is the same symptoms I suffered when timing belt skipped a few notches. Check your timing
Checked twice already and reinstalled to make sure I was right. Idles great revs up fine and then acts like a rev limiter like it's cutting out fuel.
 

turbobrick240

Top Post Dawg
Joined
Nov 18, 2014
Location
maine
TDI
2011 vw golf tdi(gone to greener pastures), 2001 ford f250 powerstroke
Maybe something gumming up the injection pump? I had a similar problem on my Kubota tractor after experimenting with high bio blends. A few moderate taps w a hammer on the pump had it back to normal.
 

[486]

Top Post Dawg
Joined
Mar 1, 2014
Location
MN
TDI
02 golf ALH
Maybe something gumming up the injection pump?
BHW=PD


Brake lamp switch? Hold both pedals down and RPM is limited somewhere around there unless you change a few things in the binary. If the switches are screwing up it'll think you're on the brake and gas at the same time.

ETA: new crank have the same reluctor wheel the old one did? New reluctor got any dents in it?
 
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FraggyTDI

Veteran Member
Joined
Jun 28, 2011
Location
Paynesville, MN
TDI
04 Jetta
Well I went ahead and pulled the cylinder off as I think it's the suspect. Sounds like cylinder two was dead at idle. And if I look at my log it's the only cylinder with a positive injection number and stays pretty much locked in. So I was thinking I damaged the injector somehow. However after a thorough inspection I double checked the exhaust manifold for blockages and it's all clear. So I dove into the injection stuff. I inspected the cam snsor pickup wheel and most all the tabs looked within a hairs distance until I came to one single tab that had been bent inward creating a large air gap. This I think is my culprit and it must of been damaged during the previous disassembly. Out of curiosity I put that tab right at the pickup up sensor and it is right at the same instance that cylinder two valve is at or close to full open. What a needle in a haystack stack now I just need to get some gaskets and get it back together.
 

FraggyTDI

Veteran Member
Joined
Jun 28, 2011
Location
Paynesville, MN
TDI
04 Jetta
Thought I would close this thread out for anyone who has an issue in the future. Turns out the cam may of been a contributing factor but I was able to render it out by replacing it with a new cam hub and sensor. After that my code for the cam signal being implausible had gone away. However I still had the issue, I then scanned codes again and a new code for the G28 sensor being implausible. I had already replaced the sensor so was sure it wasn't that leaving me with one option....Crank pickup wheel. I used my endoscope to look through the sensor hole. This is what I found


For reference this is what it looks like when good


Hope this helps anyone in the future that rebuilds an engine. Be sure to check your pickup wheel before you close up the engine.
 
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