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Random loss of throttle response from pedal

I’ve got an '04 VW Golf that has recently taken to occasional bouts of no throttle response from the accelerator pedal. This has happened a handful of times during the past few months and until this morning occured only while driving on the highway at a constant rate of speed (~58-60mph). What happens is the engine will start to decelerate as though I’ve taken my foot off the gas but my foot hasn’t moved off of the accelerator. The car’s a manual transmission and for no good reason I usually shift into 4th gear (out of 5th) slap down the accelerator pedal a couple time to rev the engine while the cluth is depressed between gears and the accelerator will wake up and I’ll get throttle response again and all’s well. This morning it happened twice on the highway and once in first gear starting from a stop at an intersection. I’m worried I may not make it home… This is Minnesota and it’s very cold – could it have something to do with the temperature?

Woops, I should clarify that when I stomp at the accelerator while shifting to “wake” the accelerator/throttle up the engine doesn’t necessarily rev at first – I’ll stomp on it a few times until I get a response from the tac to let me know things are “engaging.” The first couple stomps are usually in vain.

If you have the 1.8T Engine then your vehicle has a “fly by wire” throttle…meaning you have no direct connection between your foot and the engine… This connection has been made via cable for the last hundred years…NOw we need to get fancy pantsy and add fly by wire…Do you recall the toyota issue of late…with them driving off accelerating on their own…Fly by wire issues…

If it is drive by wire then it must be sorted out…you need to tell me what engine you have… If it isnt a fly by prob…your vehicle may be going into limp mode… Really need to know your engine here…

Not sure if they left the throttle alone on the other engines…but the 1.8T def has it

Before you go to the dealer which is where a fly by prob will be addressed…Please tell me your engine…Golfs can have quite an array… The 1.8T, the 2 point SLOW…the vr6…and the TDi

When this occurs do you have any lights on the dash lighting up like the CEL light or anything unusual?

I guess you missed the memo. The NHTSB has concluded that no electronic issues (be they with hardware or with software) can be found with the Toyota electronicaly activated throttle. New information has also come out in regards to both the tragic accident involving the off duty CHP officer (may he and his family members rest in peace)and unintended acceleration complaints in general. It seems the car that crashed was a rental and the customer before had complained about the floor mat causing the throttle to stick. The chain of events involves an auto detailer putting the wrong floor mat in this car and the person recieving the complaint about the floor mat cusing the gas pedal to stick not relaying the previous renters complaint.

It has also been shown that the number of unintended acceleration complaints increased as publicity about the case involving the CHP officer increased.

Toyota has been cleared, period.The NHSTB went on to say that the design used by Toyota for the electronic section of the throttle system was “well designed”.

It could be a clogged fuel filter or a dying fuel pump, among other things.

The engine is a 2.0 4-cyl; not the 1.8 turbo. I don’t know off hand if it’s a drive-by-wire or not but I can check the engine head and confirm.

RE the fuel pump or filter: I thought about this as well but I’m thinking it isn’t as the engine will idle without trouble and doesn’t sputter when the issue comes up. I don’t know enough about this to say with certainty that it isn’t, though.

Thanks everyone for your input – it’s greatly appreciated.

Who cares about the memo…the POINT is if they have a fly by wire it needs to be checked…that was why I mentioned it I dont care about what toyota problems were…it was just a reference to a POSSIBLE fly by wire issue in most recent memory. I just used it as an example to define the type of throttle he may have thats all. Memo…

I’m having the same issues with my 2003 VW Jetta (however it IS a 1.8T). So far I’ve had the fuel pump changed 2x, fuel filter, fuel pump relay, and air intake meter all checked/replaced. My mechanic is now stumped and is exploring some sensor issues, possibly the impulse sensor. I live in Cali so it’s prob not the weather, however just to warn you mine has continued to get worse. Now I can drive it about 1.5mi before it looses acceleration and stalls and it wont start again for about 5-7 minutes. Somebody Help!

Has your mechanic hooked it up to a scantool and driven it around to pick up live data from the engine management system? This should be done.

Your MAF sensor is the most likely suspect, but without the data from the engine I can only relay what the most common sensor failure is on the 1.8T

Pull it out and clean it off with carb cleaner or use the MAF cleaner spray they have…any good quik dry solvent should do the trick…cheap and ez fix if it works. Also check the condition of your air filter…actually…first…

I agree with you about the memo. It means nothing other than the fact that during testing any intermittent electronic fault did not show up during that particular test and whose knows what politics are behind that memo. Everyone knows that you can trust the government to tell the truth. :wink:
What code would the ECM show for a runaway car? :slight_smile:

In case anyone missed it, there was a show on TV the other night about aircraft accidents. The investigator stated that over the last few decades with the introduction of fly by wire that most accidents have been caused by electronic glitches and sometimes the failure of the flight crew to wade through the problem and manually override the problem.
That might be hard to do if you’re plummeting towards the ground at 500 MPH with no control of the aircraft.

Hundreds of millions of dollars are spent in aircraft design and they routinely have electronic faults; often leading to a smoldering crater and everyone on board dead.
Why is a lowly car supposed to be the exception?

The investigation is not over just yet. At the top of everything you generally have a den of thieves and/or incompetents.

Can also be a vacume leak throwing the ECU into limp mode…but you would have a CEL on for sure if it was that…

No he hasn’t, I’ve quickly realized I took it to the wrong guy. But now I’ve invested so much money in him I’m kinda stuck cuz he’s not charging me labor now.

The next time it does it, try this.
Lift your foot off the gas pedal, hook your other foot under the brake pedal and pull up on it. Now try the gas pedal.

I could do without ABS…Stability COntrol…Fly By Wire… ALL OF IT…

I never had an accelerator cable snap on me…or make me drive thru my garage…or shut my car down… All these Nanny Electronics have been foisted upon us…I dont want most if not all of them.

How about how an On Star system can show your throttle and brake position during a crash…or shut you down completely if the ops so chose to do so and all the data that the insurance companies can get from it to decide if you were at fault…F-U
…Try shutting me down in my old 65’ Dodge Coronet 440…LOTSA LUCK…

Too much Big Brother stuff going on as of late.

The fly by wire prob can save you some fuel, maybe…but there isnt a day goes by that I dont know and feel the fly by wire in my GTi…it feels like my accelerator is attached to my throttle with a rubber band… It has many other drawbacks as well from a mechanic/failure and troubleshooting standpoint as well NO THANKS…I really dont need it.

Learn how to drive so we can do away with ABS and Stability Control…I certainly dont need them.

Thx, yeah I suspected it could be the MAF or Impulse Sender. I even mentioned it my mechanic but he just blew me off. Apparently he didn’t like that I, a girl, had done my research and was telling him what to do. Ugh. Thx for the info!

I’m not convinced this is the problem but an intermittent fuel pump can cause a problem like this. Pump failures are not always a yes they work, no they don’t thing.

The MAF is mentioned and that is a good suggestion. The entire intake tract between the throttle plate and MAF sensor should be carefully inspected for any leaks no matter how small.

Last summer I had an erratic bucking/near stalling at times with my Lincoln and it was due to a razor type split in a breather hose. I could set the cruise on that car at 75 MPH and go for a hundred miles without a hiccup.
Slow down and attempt to accelerate out of a sweeping curve or something like that and the car would buck like it’s running out of gas. It would also only do this on occasion, not all of the time.

(The problem was a 1/2" long razor split in a softened breather hose and it would open up under certain acceleration conditions and this would throw the MAF off. Bad part is there were no codes present, even MAF codes.)

Sureley…those razor splits can drive you NUTZ…they close up when the engine isnt flexing its mounts…But get on the gas from a stop and the engine twists under the hood opening up those types of cuts and BAM…it falls on its face because the MAF will get erroneous readings bec much of the air is diverted around that sensor…to the engine it was as though you werent asking for much throttle.

Yes…check that Air filter and then go to the MAF then look for cuts or breaks in ANY vacume line…they are VERY sensitive to vac leaks ESPECIALLY being TURBO’D…

So, I’m the one with the '03 Jetta with the same prob. I’ve already had my fuel pump, filter and more replaced with no avail. However I just spoke to my mechanic and he said the problem is the Coolant Sensor as well as the air intake meter so finger’s crossed that’s it. Either way, hope this gives you a direction to go in with your Golf. G’luck!

Actually I found out he did try the computer but because the check engine light is not on there aren’t any codes being kicked out…at least that’s what he said. Who knows.