Engine Flat Spot

September 15, 2007

MY CAR IS A 2003 AVENSIS D4D T3S SHOWING 80000 MILES ,I HAVE A PROBLEM WHICH SEEMS

TO OCCUR AFTER OR DURING MOTORWAY JOURNEYS.WHEN THE CAR HAS BEEN TRAVELLING AT A

STEADY SPEED OF 70 MPH AND I SLOW CAR DOWN FOR A DEVELOPING HAZARD AHEAD THEN

TRY TO ACCELARATE AGAIN THE ENGINE LOSES POWER SO I HAVE TO DROP A GEAR AND WAIT

FOR TURBO TO KICK IN THIS IS ACOMPANIED BY A BLAST OF BLACK SMOKE OUT OF EXHAUST.IT

APPEARS TO BE A FUEL STARVATION PROBLEM TO ME. CAR HAS HAD FUEL FILTER CHANGED

AND BEEN TO TOYOTA DEALER FOR ECU REPROGRAM,AND A FUEL ADDITIVE HAS BEEN TRIED.

THE FAULT REMAINS!!! ANY IDEAS WELCOME TO RID THIS PROBLEM,LOOKING ON FORUMS

FOR OTHER MAKES OF CARS SOMETHING CALLED A EGR VALVE BECOMING PARTIALLY BLOCKED

PRODUCES A SIMILAR FAULT, COULD THIS UNIT BE THE CULPRIT???ANY SUGGESTIONS WELCOME.

September 15, 2007

MY CAR IS A 2003 AVENSIS D4D T3S SHOWING 80000 MILES ,I HAVE A PROBLEM WHICH SEEMS
TO OCCUR AFTER OR DURING MOTORWAY JOURNEYS.WHEN THE CAR HAS BEEN TRAVELLING AT A
STEADY SPEED OF 70 MPH AND I SLOW CAR DOWN FOR A DEVELOPING HAZARD AHEAD THEN
TRY TO ACCELARATE AGAIN THE ENGINE LOSES POWER SO I HAVE TO DROP A GEAR AND WAIT
FOR TURBO TO KICK IN THIS IS ACOMPANIED BY A BLAST OF BLACK SMOKE OUT OF EXHAUST.IT
APPEARS TO BE A FUEL STARVATION PROBLEM TO ME. CAR HAS HAD FUEL FILTER CHANGED
AND BEEN TO TOYOTA DEALER FOR ECU REPROGRAM,AND A FUEL ADDITIVE HAS BEEN TRIED.
THE FAULT REMAINS!!! ANY IDEAS WELCOME TO RID THIS PROBLEM,LOOKING ON FORUMS
FOR OTHER MAKES OF CARS SOMETHING CALLED A EGR VALVE BECOMING PARTIALLY BLOCKED
PRODUCES A SIMILAR FAULT, COULD THIS UNIT BE THE CULPRIT???ANY SUGGESTIONS WELCOME.

What I do know of EGR valves are Discovery owners tend to blank them off for the following reasons.

You take your foot off the power the EGR valve opens to recurculate the exhaust gasses, because they still contain unburnt fuel, but this fills the intercooler with hot exhaust gasses and gives a horrid flat spot on acceleration.

Also that my D4D dosn't do this, my best power is available from 2500 rpm probably 80mph in 5th, Sometimes when it seems a bit sluggish uphill overtaking hot days etc slightly lifting the pedal and reappliing more gradually gives more of a kick.

Maybe disconecting the EGR valve would show if this improves things it must be a valve in a pipe exhaust side of the turbo to the air intake.

good luck.

September 26, 2007

MY CAR IS A 2003 AVENSIS D4D T3S SHOWING 80000 MILES ,I HAVE A PROBLEM WHICH SEEMS
TO OCCUR AFTER OR DURING MOTORWAY JOURNEYS.WHEN THE CAR HAS BEEN TRAVELLING AT A
STEADY SPEED OF 70 MPH AND I SLOW CAR DOWN FOR A DEVELOPING HAZARD AHEAD THEN
TRY TO ACCELARATE AGAIN THE ENGINE LOSES POWER SO I HAVE TO DROP A GEAR AND WAIT
FOR TURBO TO KICK IN THIS IS ACOMPANIED BY A BLAST OF BLACK SMOKE OUT OF EXHAUST.IT
APPEARS TO BE A FUEL STARVATION PROBLEM TO ME. CAR HAS HAD FUEL FILTER CHANGED
AND BEEN TO TOYOTA DEALER FOR ECU REPROGRAM,AND A FUEL ADDITIVE HAS BEEN TRIED.
THE FAULT REMAINS!!! ANY IDEAS WELCOME TO RID THIS PROBLEM,LOOKING ON FORUMS
FOR OTHER MAKES OF CARS SOMETHING CALLED A EGR VALVE BECOMING PARTIALLY BLOCKED
PRODUCES A SIMILAR FAULT, COULD THIS UNIT BE THE CULPRIT???ANY SUGGESTIONS WELCOME.
What I do know of EGR valves are Discovery owners tend to blank them off for the following reasons.
You take your foot off the power the EGR valve opens to recurculate the exhaust gasses, because they still contain unburnt fuel, but this fills the intercooler with hot exhaust gasses and gives a horrid flat spot on acceleration.
Also that my D4D dosn't do this, my best power is available from 2500 rpm probably 80mph in 5th, Sometimes when it seems a bit sluggish uphill overtaking hot days etc slightly lifting the pedal and reappliing more gradually gives more of a kick.
Maybe disconecting the EGR valve would show if this improves things it must be a valve in a pipe exhaust side of the turbo to the air intake.
good luck.

September 26, 2007

MY CAR IS A 2003 AVENSIS D4D T3S SHOWING 80000 MILES ,I HAVE A PROBLEM WHICH SEEMS
TO OCCUR AFTER OR DURING MOTORWAY JOURNEYS.WHEN THE CAR HAS BEEN TRAVELLING AT A
STEADY SPEED OF 70 MPH AND I SLOW CAR DOWN FOR A DEVELOPING HAZARD AHEAD THEN
TRY TO ACCELARATE AGAIN THE ENGINE LOSES POWER SO I HAVE TO DROP A GEAR AND WAIT
FOR TURBO TO KICK IN THIS IS ACOMPANIED BY A BLAST OF BLACK SMOKE OUT OF EXHAUST.IT
APPEARS TO BE A FUEL STARVATION PROBLEM TO ME. CAR HAS HAD FUEL FILTER CHANGED
AND BEEN TO TOYOTA DEALER FOR ECU REPROGRAM,AND A FUEL ADDITIVE HAS BEEN TRIED.
THE FAULT REMAINS!!! ANY IDEAS WELCOME TO RID THIS PROBLEM,LOOKING ON FORUMS
FOR OTHER MAKES OF CARS SOMETHING CALLED A EGR VALVE BECOMING PARTIALLY BLOCKED
PRODUCES A SIMILAR FAULT, COULD THIS UNIT BE THE CULPRIT???ANY SUGGESTIONS WELCOME.
What I do know of EGR valves are Discovery owners tend to blank them off for the following reasons.
You take your foot off the power the EGR valve opens to recurculate the exhaust gasses, because they still contain unburnt fuel, but this fills the intercooler with hot exhaust gasses and gives a horrid flat spot on acceleration.
Also that my D4D dosn't do this, my best power is available from 2500 rpm probably 80mph in 5th, Sometimes when it seems a bit sluggish uphill overtaking hot days etc slightly lifting the pedal and reappliing more gradually gives more of a kick.
Maybe disconecting the EGR valve would show if this improves things it must be a valve in a pipe exhaust side of the turbo to the air intake.
good luck.

November 22, 2007

MY CAR IS A 2003 AVENSIS D4D T3S SHOWING 80000 MILES ,I HAVE A PROBLEM WHICH SEEMS
TO OCCUR AFTER OR DURING MOTORWAY JOURNEYS.WHEN THE CAR HAS BEEN TRAVELLING AT A
STEADY SPEED OF 70 MPH AND I SLOW CAR DOWN FOR A DEVELOPING HAZARD AHEAD THEN
TRY TO ACCELARATE AGAIN THE ENGINE LOSES POWER SO I HAVE TO DROP A GEAR AND WAIT
FOR TURBO TO KICK IN THIS IS ACOMPANIED BY A BLAST OF BLACK SMOKE OUT OF EXHAUST.IT
APPEARS TO BE A FUEL STARVATION PROBLEM TO ME. CAR HAS HAD FUEL FILTER CHANGED
AND BEEN TO TOYOTA DEALER FOR ECU REPROGRAM,AND A FUEL ADDITIVE HAS BEEN TRIED.
THE FAULT REMAINS!!! ANY IDEAS WELCOME TO RID THIS PROBLEM,LOOKING ON FORUMS
FOR OTHER MAKES OF CARS SOMETHING CALLED A EGR VALVE BECOMING PARTIALLY BLOCKED
PRODUCES A SIMILAR FAULT, COULD THIS UNIT BE THE CULPRIT???ANY SUGGESTIONS WELCOME.
What I do know of EGR valves are Discovery owners tend to blank them off for the following reasons.
You take your foot off the power the EGR valve opens to recurculate the exhaust gasses, because they still contain unburnt fuel, but this fills the intercooler with hot exhaust gasses and gives a horrid flat spot on acceleration.
Also that my D4D dosn't do this, my best power is available from 2500 rpm probably 80mph in 5th, Sometimes when it seems a bit sluggish uphill overtaking hot days etc slightly lifting the pedal and reappliing more gradually gives more of a kick.
Maybe disconecting the EGR valve would show if this improves things it must be a valve in a pipe exhaust side of the turbo to the air intake.
good luck.

I have the same problem. I have a T3X diesel. It is fine for the first 6-8 miles. When the engine has warmed up I and I slow down for junction or try to accelarate I have little or no acceleration. If I keep my foot on the accelaerator the turbo kicks in after about 10-20seconds follwed by a blast of black smoke. Car is now with Toyaot garage for the third time as it is too dangerous to drive. I am still waiting for a fault diagnosis. At least they have now acknwoledged that there is a fault. They tested it the first time and said that there was nothing wrong.

December 17, 2007

MY CAR IS A 2003 AVENSIS D4D T3S SHOWING 80000 MILES ,I HAVE A PROBLEM WHICH SEEMS
TO OCCUR AFTER OR DURING MOTORWAY JOURNEYS.WHEN THE CAR HAS BEEN TRAVELLING AT A
STEADY SPEED OF 70 MPH AND I SLOW CAR DOWN FOR A DEVELOPING HAZARD AHEAD THEN
TRY TO ACCELARATE AGAIN THE ENGINE LOSES POWER SO I HAVE TO DROP A GEAR AND WAIT
FOR TURBO TO KICK IN THIS IS ACOMPANIED BY A BLAST OF BLACK SMOKE OUT OF EXHAUST.IT
APPEARS TO BE A FUEL STARVATION PROBLEM TO ME. CAR HAS HAD FUEL FILTER CHANGED
AND BEEN TO TOYOTA DEALER FOR ECU REPROGRAM,AND A FUEL ADDITIVE HAS BEEN TRIED.
THE FAULT REMAINS!!! ANY IDEAS WELCOME TO RID THIS PROBLEM,LOOKING ON FORUMS
FOR OTHER MAKES OF CARS SOMETHING CALLED A EGR VALVE BECOMING PARTIALLY BLOCKED
PRODUCES A SIMILAR FAULT, COULD THIS UNIT BE THE CULPRIT???ANY SUGGESTIONS WELCOME.
What I do know of EGR valves are Discovery owners tend to blank them off for the following reasons.
You take your foot off the power the EGR valve opens to recurculate the exhaust gasses, because they still contain unburnt fuel, but this fills the intercooler with hot exhaust gasses and gives a horrid flat spot on acceleration.
Also that my D4D dosn't do this, my best power is available from 2500 rpm probably 80mph in 5th, Sometimes when it seems a bit sluggish uphill overtaking hot days etc slightly lifting the pedal and reappliing more gradually gives more of a kick.
Maybe disconecting the EGR valve would show if this improves things it must be a valve in a pipe exhaust side of the turbo to the air intake.
good luck.
I have the same problem. I have a T3X diesel. It is fine for the first 6-8 miles. When the engine has warmed up I and I slow down for junction or try to accelarate I have little or no acceleration. If I keep my foot on the accelaerator the turbo kicks in after about 10-20seconds follwed by a blast of black smoke. Car is now with Toyaot garage for the third time as it is too dangerous to drive. I am still waiting for a fault diagnosis. At least they have now acknwoledged that there is a fault. They tested it the first time and said that there was nothing wrong.

We have the exact same problem on my wife's 53 D4D T2. It has started loosing power at intermittent intervals, but particularly at junctions when pulling away after having stopped. There is also a puff of black smoke emitted when the flat spot finally clears and the car races off again. The car has just been serviced with new oil, fuel filters and diesel cleaner and there doesn't seem to have been any improvement.

Any solutions would be gratefully received as the car is now potentially dangerous to drive.

December 18, 2007

To Philthefuel,

Have same model vehicle with 90,000 odd miles on it. Your EGR valve is a mechanical device as your aware either working of eng-vacum or in some cases electrical signal. If Toyota run a check on system & no error codes showing ie: map sensor etc witch can in some cases cause same problem. It still is highly likely that your EGR valve is sticking in open position, with the effect that car feels like someone has thrown a big anchor out off the window. At your milage it would be possible or quite likely for EGR valve to be well coked up or full of carbon deposits causing the valve to stick on ocassion. May well be worth returning to Toyota & pointing out what you consider to be the problem. See how much it costs to change , may well be money well spent. I work for another car manufacturer & it is quite a common fault on diesel models, not being a major job to carry out. Could be well worth your money to change component via Toyota. For example if you have to have MOT carried out & valve is playing up, upping your emmissons you would find it hard to past. Good Luck.

January 1, 2008

:yahoo: Just for those members who, like me, get frustrated at reading questions but don't always get to read the answers...here's some good news.

Took our Avensis D4D to Inchape Toyota to try and sort. (Had severe reservations going to this main dealer after they quoted me 800 pounds plus for an offside drive shaft - when in fact all it needed was a wheel bearing!) They were very helpful and suspected that the problem was due to the EGR valve being coked up. They duly took it out and cleaned it up and then refitted. Car now works perfectly once more. :thumbsup: