Flat spot on accelaration
Discussion
Hello,
It's groovy having such a new forum.
I recently purchased my 156 and have been spending the last few months getting to know it. It's a 2.5 V6, drives superbly etc etc.
One thing I have noticed is it has a poor throttle response lower down the rev range. Anyone else notice this and what can be done to improve it?
It's groovy having such a new forum.
I recently purchased my 156 and have been spending the last few months getting to know it. It's a 2.5 V6, drives superbly etc etc.
One thing I have noticed is it has a poor throttle response lower down the rev range. Anyone else notice this and what can be done to improve it?
It's second hand, '98 with 80K on the clock. The service history is immaculate, had the big service done at 65K, cam belt and tensioners all done. Drives really well, plus no oil burn. I check the oil religiously twice a week, and it just hasn't moved on the dipstick.
The flat spot is in all gears. Above about 4200rpm it's fine, and pulls away like a train. Below that it can be quite annoying. Today, I pull out onto a dual carriageway, and in an effort to get up to speed, tickled the loud peddle a bit. Got it upto about 4500 in second and then changed to third, revs dropped to 3500 and all the power goes, the car feels like it's slowing down, until it hits 4000 rpm in 3rd and then starts to pull away again.
It's more frustrating than anything else. I don't drive like a lunatic, and more often than not I'm happy to drive at 60 on the m'ways. It's just something I have noticed after driving this car for a while.
What do you think I should do? It's covered under a warranty, do you think it's worth speaking to the garage I bought it from?
The flat spot is in all gears. Above about 4200rpm it's fine, and pulls away like a train. Below that it can be quite annoying. Today, I pull out onto a dual carriageway, and in an effort to get up to speed, tickled the loud peddle a bit. Got it upto about 4500 in second and then changed to third, revs dropped to 3500 and all the power goes, the car feels like it's slowing down, until it hits 4000 rpm in 3rd and then starts to pull away again.
It's more frustrating than anything else. I don't drive like a lunatic, and more often than not I'm happy to drive at 60 on the m'ways. It's just something I have noticed after driving this car for a while.
What do you think I should do? It's covered under a warranty, do you think it's worth speaking to the garage I bought it from?
Sounds more like that's just how it is.
I know the T-spark engine has a variable length airbox that opens up at a certain point, releasing more power & noise. Not sure if the 2.5V6 is similar.
In my 3.0V6, there's a fair bit of torque below 4k, but the best stuff starts at about 4200. To be honest, in day to day driving, I rarely get above 4krpm (that's just over 100mph in 6th!) and its a revalation when you find a good bit of road for a proper blast.
From what I gather, on the 3.0V6, a dodgy airflow meter seems to manifest itself either as a complete loss of power & undriveable car or a pronounced flat spot at about 5krpm.
I know the T-spark engine has a variable length airbox that opens up at a certain point, releasing more power & noise. Not sure if the 2.5V6 is similar.
In my 3.0V6, there's a fair bit of torque below 4k, but the best stuff starts at about 4200. To be honest, in day to day driving, I rarely get above 4krpm (that's just over 100mph in 6th!) and its a revalation when you find a good bit of road for a proper blast.
From what I gather, on the 3.0V6, a dodgy airflow meter seems to manifest itself either as a complete loss of power & undriveable car or a pronounced flat spot at about 5krpm.
I have 2001 v6 lusso, 22K F alfa SH, i'm the second owner. The v6 is a peaky motor for sure, above 4k revs there is alot more power/torque and it really goes, you just need to use all six gears !! Its a bit like a jap 4 cyl bike!!! One problem which has recently come up is it is running hot in traffic, 110c instead of the usual 90c, both fans are working so I suspect a bloken rad. and duff waterpump. Am taking into a dealer next week. Also the lusso suspension is far too soft and spongey, although this does make for an amusing drive on the limit !!!
number 46 said:
I have 2001 v6 lusso, 22K F alfa SH, i'm the second owner. The v6 is a peaky motor for sure, above 4k revs there is alot more power/torque and it really goes, you just need to use all six gears !! Its a bit like a jap 4 cyl bike!!! One problem which has recently come up is it is running hot in traffic, 110c instead of the usual 90c, both fans are working so I suspect a bloken rad. and duff waterpump. Am taking into a dealer next week. Also the lusso suspension is far too soft and spongey, although this does make for an amusing drive on the limit !!!
Is it running hot all the time?
The reason I ask is that mine occasionally gets hot, not too hot and not for too long. I have noticed the engine bay generally does tend to get quite warm, thought that was just a characteristic of the V6.
I may pop down to my local dealer and see what they have to say. I got a three year warranty when I bought the car, so if anything is amiss hopefully that will help.
Has anyone here got uprated suspension or wheels? I am thinking of changing the standard set up on mine for something a little more sporty...
It's not lighting the 'red light' on the temp. gauge so not critical, but is certainly running hotter than it did in the first few months of ownership. The top of the rad core has little rust/antifreeze stains so I suspect a partial blockage in the rad, although it isn't losing water. the trip too the dealer should sort it out and of course it should be free as it is still under warranty. I suspect that there isn't much cooling margin on the v6 as it is such a tight fit in the engine bay and has a small rad. and grill to allow the air in. However it still is a great car for the money with a lively performance !!!!
The new petrol Alfa engine are all quite guilty of flat spots in many instances. Right enough, a published cure in the AROC mag is to have the car chipped. This removes areas of very lean fuelling (put there for emissions reasons). Your car will not require a chip as such. I think it's a '98 or later and therefore will only require a ECU remap. This does the same thing but you don't actually change a chip- only the software programme to run it. Our workshop would diversify into this area if we had more capital and a larger market to tap into. I suggest you try "sales@reddotracing.co.uk" as they appear to be notable in Alfa remaps. Do be aware though, if you change the mapping, Alfa diagnostic equipment will not read your ECU's data and it will need to be returned back to spec before any diagnostic work is performed should a subsequent fault occur!
If it is pre '98, just fit a chip. I personally intend to opt for a Squadra chip in the comming months. This has specific fuelling and timing for 98 octane petrol and will yield higher gains over a normal chip. Super unleaded or Optimax is a better petrol as it has a slower burn rate and gives a more sustained push on the piston crowns. This is why it needs the ignition to be slightly advanced over 95 octane fuel.
The other likely suspect is that the lambda sensor is starting to play up. These typically last around an average of 80000 miles in Alfas but they can fail very quickly or last the car's life.
I think it is the over lean mixture though, so I think you will soon be enjoying even more performance from a performance 'chip'!
If it is pre '98, just fit a chip. I personally intend to opt for a Squadra chip in the comming months. This has specific fuelling and timing for 98 octane petrol and will yield higher gains over a normal chip. Super unleaded or Optimax is a better petrol as it has a slower burn rate and gives a more sustained push on the piston crowns. This is why it needs the ignition to be slightly advanced over 95 octane fuel.
The other likely suspect is that the lambda sensor is starting to play up. These typically last around an average of 80000 miles in Alfas but they can fail very quickly or last the car's life.
I think it is the over lean mixture though, so I think you will soon be enjoying even more performance from a performance 'chip'!
Thanks for all the help and advice. Been busy the last few weeks, but managed to get the car down to Ken Bell in Fleet, who was a star, I owe that man a 
Anyway,, he ran a full diagnostic, which showed no errors appearing. So we took it out for a spin, and true to form, the car wouldn't accelerate, stuttered and generally sounded poorly. Ken said his best guess was the Air Mass Meter. So paid up Ken ( a small fee and well worth it, top chap!) and called Warranty holding expecting an arguement over who should pay for a replacement.
To my suprise, WH were also on top form, and agreed that the part could be replaced under warranty, so I duly called the garage I bought the car and warranty from ( I was on a roll by this point) and they got it book in on Tuesday 27th.
Dropped off the car, went to work, couple of hours later got a call from the garage saying the car was ready to collect, not a penny to pay.
Needless to say I knocked off work a little bit early and picked up the car
What a difference. Car now feels like it should. Smooth through the gears and the scream of the V6 at 6000RPM is awesome. Obviously I was being careful to warm the car up first, and with the cold weather was being especially careful when and where I accelerated.
So, all in all, success. I will be writing a letter of thanks to the Garage that carried out the work, (Phoenix garage in Hartley Witney
) and now will mostly be looking at getting 17" wheels, better suspension and possibly a remap... :wink:
>> Edited by banjolucknicker on Wednesday 28th January 09:15
Anyway,, he ran a full diagnostic, which showed no errors appearing. So we took it out for a spin, and true to form, the car wouldn't accelerate, stuttered and generally sounded poorly. Ken said his best guess was the Air Mass Meter. So paid up Ken ( a small fee and well worth it, top chap!) and called Warranty holding expecting an arguement over who should pay for a replacement.
To my suprise, WH were also on top form, and agreed that the part could be replaced under warranty, so I duly called the garage I bought the car and warranty from ( I was on a roll by this point) and they got it book in on Tuesday 27th.
Dropped off the car, went to work, couple of hours later got a call from the garage saying the car was ready to collect, not a penny to pay.
Needless to say I knocked off work a little bit early and picked up the car
What a difference. Car now feels like it should. Smooth through the gears and the scream of the V6 at 6000RPM is awesome. Obviously I was being careful to warm the car up first, and with the cold weather was being especially careful when and where I accelerated. So, all in all, success. I will be writing a letter of thanks to the Garage that carried out the work, (Phoenix garage in Hartley Witney
) and now will mostly be looking at getting 17" wheels, better suspension and possibly a remap... :wink: >> Edited by banjolucknicker on Wednesday 28th January 09:15
I run a company performing ECU remapping specialising in Alfa's and Fiats and just want to clear a couple of things. The remap changes the data that the engine management programme uses not the programme itself.
Remapping does not affect the ability of the diagnostic equipment to read error codes or in fact any of the data held on the ECU so you dont have to have the original loaded back on.
Apart from that, AlfaMad was spot on and it really is the way forward for more power, economy in some cases and a smoother delivery with improved throttle response.
Remapping does not affect the ability of the diagnostic equipment to read error codes or in fact any of the data held on the ECU so you dont have to have the original loaded back on.
Apart from that, AlfaMad was spot on and it really is the way forward for more power, economy in some cases and a smoother delivery with improved throttle response.
AlfaNige is right. I'm from Monza Sports Tuning. A re-map will not affect the diagnostic codes.We have developed a modified file for re-mapping Alfa 2.0 Twin Spark engines which amongst other things specifically addresses the flat spot between 2-3000 rpm. It also increse bhp torque and throttle response. A rolling -road print-out can be seen at www.monzasport.co.uk/tuning.htm
The torque graph between 2-3000rpm is the one to look at! We also tuned the first Diesel car ever to win a race at Castle Coombe last year - an Alfa 156 Sportwagon 2.4 JTD!!! We are working on a modified file for the 2.5V6 and will keep you posted!
PetrolTed: Monza checked with me before posting so please don't jump down his throat for advertising
The torque graph between 2-3000rpm is the one to look at! We also tuned the first Diesel car ever to win a race at Castle Coombe last year - an Alfa 156 Sportwagon 2.4 JTD!!! We are working on a modified file for the 2.5V6 and will keep you posted!
PetrolTed: Monza checked with me before posting so please don't jump down his throat for advertising
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