LIMP MODE Q&A

LIMP HOME MODE

When I initially bought my VW Polo 2.0L she was a thrill to drive. Her speed was instant, cornering was really good and road holding never better. She was a joy to drive, very unlike my VW Golf II, but then I started getting car troubles,  which were many and varied. My first encounter with VW agents was a disaster. After they "repaired" my EPC fault they charged me a ridiculous sum of money, only to experience the same EPC problem the following day.  After speaking to several of their mechanics, who collectively were unable to fix my car, I came to realize  that I was either far more knowledgeable about automotive electronics than all of them put together, or they knew very little about electronics.  This just put me off the agents completely and when I took my Polo to independent mechanical workshops,  I found the same to be true. I still remember how lost I felt when my VW Polo went into limp mode the first time and the second and the third and the fourth. I felt lost, stuck on the freeway, late for meetings, frustrated and miserable because I couldn't repair her like I did the VW Golf II due to the fact that the Polo had OBD-II. I  thought my VW Polo to be unreliable, there was a point that I feared driver her at night, and later started to hate  even diving the Polo.  I was literally on the verge of setting her alight. But them I decided to buy a Ross Tech cable and downloaded their VCDS and my Polo is a joy to  drive once again. The rest of this blog is devoted to 10 vehicles owners who have experiences similar trouble with their VAG vehicles ranging from Drive by wire problems, to EPC trouble, to DTC trouble Codes to CAN-Bus-issues to name but a few. 

DRIVE BY WIRE
Steve sent this:- Had the problem of no power, tried the technique described in your blog (disconnect battery, wait, reconnect, turn ignition key, wait, turn off, turn engine on, wait, press throttle...) - and it worked beautifully. Many thanks for your help, very much appreciated - particularly as you've probably save me many pounds. 

QUESTION? - DRIVE BY WIRE
Anonymous sent this:- I have a '07 Polo 1.4 16v BUD. I don't have any lights on the dash, but the engine seems really weak through mid revs and is using a bit too much fuel. When I hook up my OBDII there are no faults recorded but when I view the throttle position in real time it doesn't seem to open in a linear manner. As I press the pedal on the road, the throttle valve seems to open slower than the position of  the pedal. eg; 50% pedal = 30% throttle position, 80% pedal = 35% throttle, 95% pedal = 40% throttle, 100% Pedal = 100% throttle. As you can see WOT does give WOT at the throttle body, but I don't generally drive with my foot planted on the floor. I am confused why it does this as you would expect the throttle body to open the same amount as the pedal, could it need alignment? I am loathed to take it to the VW dealer for fault diagno$i$ so if anyone has any ideas????  Thanks 

ANSWER!
On drive by wire model vehicles the throttle doesn't open like legacy cable throttles because its electronically controlled. 

DRIVE BY WIRE
Durell  Dunn  left this:- I am currently experiencing the same problem with my 2003 polo,1.4. The car goes into limp mode and on some occasions switches off in traffic, hectic ! I will use your method. Thank you for saving me from going to a VW dealership, all I can do at this stage is do and hope 

DRIVE BY WIRE
Loci sent this:- Hi. I have a problem with my Volkswagen Polo 1.4 Tdi. It seems to have a good start but after I drive for around 35 minutes it loses the power so I could not pass 2000 giro. Thank you for your suggestions.

QUESTION? - DRIVE BY WIRE 
Anonymous asked:- My car is a polo 1.4 2012 model. When I start the car the EPC light switch on then I put gear to move the car but it limbs then I switch it off then start it again then the EPC light does not switch on then off I go... What could be wrong? 

ANSWER!
The trouble can be one of many things, among which are your accelerator pedal, throttle body, knock sensor, Fuel pump pressure, even a loose fuel cap. You need to check through each systematically but for that you at least need a scan of your vehicle.

ENGINE LIGHT COMES ON
Lee Kyprian left this:- Everyone who has ever owned a car has experienced the confusion and even panic which can arrive when your check engine light suddenly comes on.

QUESTION? VW ELECTRONIC POWER CONTROL
Abror Isoqov sent this:- Hello. My car is VW Golf 1.6 16v and I have a problem with acceleration it has no enough power. It accelerates very slow and at 5th gear it can get max 130 km/h. At neutral position when engine gets about 5000 rpm the EPC light comes on. After restarting the engine it goes off. Tester didn't determine any trouble codes. What can cause for this problem. I went about 7-8 auto services but any of them could help. But I didn't go to VW dealer because it will be very expensive. last time they charged me $125 just for diagnostic.  Please help me with this issue.   

ANSWER!
What you explaining is limp mode and everything else seems very odd. Because by the time the EPC light does go on, a DTC is already set which any scan tool should be able to retrieve. Unless there is a problem with you DLC wiring, so that communication between vehicle and scan tool is erroneous.

VW ERROR CODES
Steve Cain sent this:- Hi, vw polo 1.4tdi 2003, AMF engine code,  problem is that when driving at any speed, car looses all power, engine stuck on 1200 rpm, throttle pedal no response, glow plug heating light flashes, switch off & switch back on straight away, car drives normally, no warning lights. Can you shed any light on this problem, (driving my wife mad). Thanks, Steve 

ANSWER!
I have covered this problem quite substantially in previous blogs and it in your interest to ready through them.

WON'T REV
Anonymous sent this:- My VW Jetta 2002 1.8t stopped me on the highway and it refused to rev and the mechanic says it is the brain box. I don't understand is he correct?

ANSWER!
Yes he is correct, problem lies in the ECM circuit but not necessarily the ECM itself. Dude you need to get your car scanned to get a better idea of  the actual problem.

CAN-BUS
Hi! I read your blogs and saw writings from you  about the CAN bus protocol. I have a problem to understand something on my cars OBD connector and the CAN bus line. Can you please help me maybe? Can we talk about? When I connect my 2 channel  DSO to the OBD connector pin 6 and pin 14 ( CAN-H and L ) and pin 5 (GND) on my VW Polo 1.4D year 2003 I got this signal what I posted right now. But, when I do the same think on my Renault Clio 1.5DCI year 2003 I got the right CAN signal.  

ANSWER! 
The likely hood is that your VW Polo isn't CAN compliant because its still a 2003 and used KWP-1281 and KWP-2000 protocols.  All VW's after 2008 is fully CAN compliant.