BEW No gas pedal response on cold start
- Thread starter bmw
- Start date
Seems as if it actually wasnt burning oil, the gas pedal just "Lags" so to speak... I was holding it down and it just wasnt registering that I had pressed it for like 15-30 seconds or so causing me to believe it was doing it on its own, just confirmed today that that was not the case though. Oil level is good. Got a slight valve cover leak but I dont intend on wasting 500$ on a new valve cover lol, replaced the gasket several times over my years of ownership and seems the cover itself is just warped.. the bluish smoke i was seeing was just the drippage burning off the exhaust manifold. I seem to have contracted a nasty viral infection so wont be able to put the crank sensor in until im feeling better... its like nearly -20 celsius every day now here
~TDIguy~
Veteran Member
Mine does the deal like BMW described on a regular basis, the bogging down and then revving up with plenty of smoke. It started, however, since the belt broke and the torsion is not dialed in correctly yet. I'm wracking my brain as to what else would change to make it go back to an operational pedal.
My car will do the 1100 rpm idle and non responsive pedal and during this period the turbo is not audible. As soon as it drops down to normal rpms you can hear the turbo wake up, and consequently the exhaust sound changes and the pedal also starts working all at once... Almost reminds me of the old ford 7.3s that would partially block off there exhaust on a cold start to help warm the engine up faster. Just sitting here putting into words my random thought processes
My car will do the 1100 rpm idle and non responsive pedal and during this period the turbo is not audible. As soon as it drops down to normal rpms you can hear the turbo wake up, and consequently the exhaust sound changes and the pedal also starts working all at once... Almost reminds me of the old ford 7.3s that would partially block off there exhaust on a cold start to help warm the engine up faster. Just sitting here putting into words my random thought processes
Yesterday morning I started it up, pedal worked fine, backed it out of my drive way, then sudden loss of power and it died, started it back up and the pedal wouldn't work at all. I shut it back off, cycled the key and waited for the glow plug light about 4 cycles, fired it back up and it was fine. I put a new genuine crank sensor in it and got a homebrew tune done and it hasn't acted up as of yet, took in on a good 5 trips since. Seems if the crank sensor was attributed to the intermittent dying as soon as starting issue.
Seems as if the gas pedal only doesnt work when i start the car right away, if i cycle the key to activate the glow plugs like 4 times then start the car it seems to never have an issue. All the temp. sensors showed plausible values though, i wonder if one temp sensor is intermittently acting up, telling the ecu that its -40 or something stupid which cuts the gas pedal to act as a fail safe to prevent loading the engine when its super cold out. anyone know of any temp sensors which are common fail items on these cars? seems like ive exhausted all other options diagnosis wise, and i dont really want to keep shooting the parts cannon at the car.. already spent far too much on the thing lol, probably more than its worth at this point
~TDIguy~
Veteran Member
Wow i have no idea... still acting up then eh?
BlueMk4Golf
Member
had something happen smilar to me. My pedal didnt work after driving in rain, and huge pudels with water. The things that may be broken or maybe isnt working as they should are eiter your ECU. Not getting any information that the pedal is beeing pushed on, or your TPS, throttle position sensor.
These may have been mentioned. Sorry but i didnt take the time to read the whole thread
Sent fra min SM-G960F via Tapatalk
These may have been mentioned. Sorry but i didnt take the time to read the whole thread
Sent fra min SM-G960F via Tapatalk
No pedal response issue still happening intermittently, the TPS is brand new. The new crank sensor has fixed the stalling issue. I'm in contacts with a tech at a local VW dealership, told me the temp sensor is probably the cause... however I've already changed the one located by the glow plugs and tandem pump... I'm not sure of any others, still awaiting response, will post back with my findings
arcking
Well-known member
I'm really curious to see where this goes as I have the same issue with an '04 BEW. It seems to occur primarily when it's cooler and the car has sat for a number of hours. I suspect there may be a correlation with how long I wait after starting before shifting into D. Unfortunately, I've never 'caught' the intermittent problem with VCDS pulled up to check pedal position and other values. I've been able to get pedal response back by turning the car off and then back on (always works), waiting for a few minutes, and occasionally shifting from D to P to D again.
DuraBioPwr
Veteran Member
Any fix or solution to this? Mine is doing same thing. I wonder if there is a fueling lockout due to low oil pressure as in maybe its a dodgy oil pressure sender.
flan
Veteran Member
Mines done this forever. Usually won’t last more then 10sec on a below freezing cold start.
DuraBioPwr
Veteran Member
Its really weird. Random when it decides to do it but definently related to cold soaking of the engine. But yeah dont last long when it does it. 5 -10 seconds tops.
scurvy
Good Ol' Boy
There is no such thing, nor does the oil pressure warning light come on at idle.
I still think this could be a culprit.oilhammer said:
JDSwan87
Black Swamp Thing
- Joined
- Feb 9, 2014
- Location
- Michigan near Toledo
- TDI
- 2001 Jetta TDI, 5 speed Lagoon Blue Metallic(sold); 2005 Jetta TDI Wagon auto
My BEW does this also. I happen to run a scan gauge and the "TBO" (requested boost) reads "-0.7" when this happens instead of the usual positive value. The MAP sensor reading on the scan gauge also reads lower than the usual 14.3. Throttle pedal input has no effect on it nor does brake pedal, e-brake, auto gear selection or restart. It seems the colder the temp, then longer it lasts.
I don't worry too much about it. I chose to drive more, worry less.
I don't worry too much about it. I chose to drive more, worry less.
DuraBioPwr
Veteran Member
Im not really worried about it either as its not an inconvinence, but if its a component dying I would like to fix prior to it turning into one. Dont think its related to brake status. Definently tied to cold weather and why would a brake switch flake out only in the cold.
wonneber
Top Post Dawg
- Joined
- Oct 12, 2011
- Location
- Monroe, NY, USA
- TDI
- 2014 Jetta Sportwagon,2003 Jetta 261K Sold but not forgotten
wonneber
Top Post Dawg
- Joined
- Oct 12, 2011
- Location
- Monroe, NY, USA
- TDI
- 2014 Jetta Sportwagon,2003 Jetta 261K Sold but not forgotten
DuraBioPwr
Veteran Member
This is driving me crazy. Mine is getting worse with the no pedal response on cold start. Cant find anything wrong! No codes. I have noticed the turbo vane position as well. When it starts there is no turbo whistle and when it decides to allow throttle the vanes close up and the the whistle starts. I wonder if it is vacuum related? As in needs to build vacuum prior to being able to move the vanes closed on the turbo. Somebody mentioned above though that the requested boost value was low while doing the dead pedal thing so vacuum build lag dont make sense.
Something in the ecm programming is not allowing normal operation due to some condition not being met.
Something in the ecm programming is not allowing normal operation due to some condition not being met.
wonneber
Top Post Dawg
- Joined
- Oct 12, 2011
- Location
- Monroe, NY, USA
- TDI
- 2014 Jetta Sportwagon,2003 Jetta 261K Sold but not forgotten
Check when you start the car if the linkage on the turbo actuator moves.
Check if the vacuum pump is producing at least 20 inches of vacuum.
You need at least that much for the actuator to pull the arm fully.
It's only 2 nuts, the plug, the e-clip and vacuum hose to remove the actuator.
You can then check if the arm going into the turbo moves full range easily w/o binding.
There's a VW bulletin about the actuators rusting internally.
Not sure if yours has this problem or not.
I wonder if the ECU senses the arm did not move and is limiting the pedal response.
Check if the vacuum pump is producing at least 20 inches of vacuum.
You need at least that much for the actuator to pull the arm fully.
It's only 2 nuts, the plug, the e-clip and vacuum hose to remove the actuator.
You can then check if the arm going into the turbo moves full range easily w/o binding.
There's a VW bulletin about the actuators rusting internally.
Not sure if yours has this problem or not.
I wonder if the ECU senses the arm did not move and is limiting the pedal response.
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DuraBioPwr
Veteran Member
wonneber, Ill check that out tonight to see if it moves freely. Zero problems with boost control though during running.
On another thread related to this someone mentioned that if the tandem pump does not make 100psi to the injectors then it might do this until pressure builds. There is no pressure sensor on the internal 'rail' in the head though so dont know how the ecm would make a decision about fuel pressure when it has no sensor?
On another thread related to this someone mentioned that if the tandem pump does not make 100psi to the injectors then it might do this until pressure builds. There is no pressure sensor on the internal 'rail' in the head though so dont know how the ecm would make a decision about fuel pressure when it has no sensor?
BobnOH
not-a-mechanic
That's what it is. I've had frozen actuator, read many a thread here, can't imagine the turbo doing that. Maybe the tandem pump, but seems unlikely. My monies on wire/connect at something like the brake switch.
arcking
Well-known member
I can't speak for others, but I can note that in my case the car did this both before and after a brand new turbo (with actuator). I was thinking it might be related to the 09A in some manner, but it seems that others with manual transmission have the same issue which would rule that out.
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DuraBioPwr
Veteran Member
arcking,
Well thats encouraging anyways its not actuator related. I checked mine the other night and seems that it moves just fine and does not 'hang' anywhere. Yup, mine is a manual car. I wish i could get some information on the run permissives in the ECU. Have no idea where to find something like that.
Well thats encouraging anyways its not actuator related. I checked mine the other night and seems that it moves just fine and does not 'hang' anywhere. Yup, mine is a manual car. I wish i could get some information on the run permissives in the ECU. Have no idea where to find something like that.
tgray
Veteran Member
- Joined
- Sep 12, 2004
- Location
- Marengo, IL
- TDI
- '02 Beetle, '05 Golf, 2000 Jetta, 2001 Jetta, 2002 Jetta
My 2005 BEW Golf has done this for years with having no throttle response on a cold start. Seems to have been more frequent lately. I tried moving the automatic gear selector back and forth and it seemed to come out of it the other day. I tried blinking the brake light and still nothing. Other times I just turned the engine off and restarted and it always came back. Keep digging for answers. I would love to find a solution. With mine it is a challenge because everything will be fine if I go to check stuff. No codes and all working fine after the first glitch in the morning. Always when it is a cold first start and never when it is warm.
arcking
Well-known member
Another interesting tidbit - I have two '04 TDI 'twins' differing only in color and the ESP option from a physical perspective as far as I know (both automatics, german-made wagons, etc) - one has this issue the other doesn't. Drives me nuts.
I have ECU dumps taken with MPPS from both of them and when compared in WinOLS the two dumps differ a bit (if I remember correctly, one appeared 'offset'). I have no idea if this is normal, but I was expecting them to be the same. Looking at these is all Greek to me, but if someone is familiar with looking at dumps/tuning and would like to compare to see if there's anything of interest let me know. EDIT - the two ECUs are running different software versions, which likely is the cause of this discrepancy.
I have ECU dumps taken with MPPS from both of them and when compared in WinOLS the two dumps differ a bit (if I remember correctly, one appeared 'offset'). I have no idea if this is normal, but I was expecting them to be the same. Looking at these is all Greek to me, but if someone is familiar with looking at dumps/tuning and would like to compare to see if there's anything of interest let me know. EDIT - the two ECUs are running different software versions, which likely is the cause of this discrepancy.
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JETaah
Vendor , w/Business number
I've encountered this on about a half dozen BEW and BHW cars and only ones with auto transmissions. Never did find the problem on any of them. After a minute or so of idling on a cold start , it works normally. no fault codes thrown. Accelerator info present, no brake signal present, swapped ECUs...it's frustrating.
MOEY
Member
Hi guys
did anybody manage to find a solution to this?
mine is doing the same.found a leak on the vacuum hose.replaced the hose and problem solved. after few days its back to square one.seems to be something to do with the vacuum lines.gonna check few more hoses later and see if anything can be picked up. I believe there's a hose that's connected to the ECU and that's a common fail.
did anybody manage to find a solution to this?
mine is doing the same.found a leak on the vacuum hose.replaced the hose and problem solved. after few days its back to square one.seems to be something to do with the vacuum lines.gonna check few more hoses later and see if anything can be picked up. I believe there's a hose that's connected to the ECU and that's a common fail.
JETaah
Vendor , w/Business number
Doubt it.
If you are working on the BEW car in your signature, the only thing operated by vacuum is the turbo actuator, an intake flap valve which only closes a small portion of the port and a diverter valve for the EGR cooler. None of those things would cause the accelerator to just not operate. You could disconnect all of those items once the car passes the no-accel episode and the accelerator would rev the engine.
There is no vacuum connected to the ECU on these cars...not since 1998.
If you are working on the BEW car in your signature, the only thing operated by vacuum is the turbo actuator, an intake flap valve which only closes a small portion of the port and a diverter valve for the EGR cooler. None of those things would cause the accelerator to just not operate. You could disconnect all of those items once the car passes the no-accel episode and the accelerator would rev the engine.
There is no vacuum connected to the ECU on these cars...not since 1998.
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MOEY
Member
Tbe car was not going over 2.5k revs
When we changed the broken vacuum hose it immediately went back to normal. Few days later now its doing the exact same thing. Im going to replace few of the old hoses and see if that solves the problem. The other option I have is to replace the glow plugs