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Cr*p electronic injection?
Alez - 22/4/08 at 09:08 AM

Hi All,

I've driven a few different cars with different fuel injection systems. For some of them (newest types), the throttle response was disgusting:

-sluggish and lots of lag;
-you could actually feel electronic closed loops acting when doing some things like parking etc;
-if driving any hard, very difficult to avoid rpms increase briefly when pushing the clutch in order to shift up due to lag (only way was to release throttle totally, wait, push clutch pedal).

I just hate all that and I would like to learn from you guys what system brought that to cars because I'm useless with mechanics. I was suspecting this would be inherent to the EFI systems. But recently I found that the MX-5 mk1 (which has a nice throttle response in my opinion) had EFI:
"
The engine employs an electronic fuel injection system using a vane-type air flow meter and a camshaft angle sensor instead of a distributor.
http://en.wikipedia.org/wiki/Mazda_MX-5
"

So now I don't know what to blame for the terrible throttle response that some cars have. I thought it would be the EFI in itself and I would have to live with carbbed cars forever because of this (I love them but they are not great for the environment).

Comments, experiences?

Cheers,

Alex

UncleFista - 22/4/08 at 09:20 AM

It's all emmisions bollox, throttle must open and close smoothly, fuel cut at any excuse etc.

I'm sure that if you could map a modern car yourself most problams would go away

Mr Whippy - 22/4/08 at 09:27 AM

I found many modern cars to be very sluggish reducing revs, especially when changing gear or even the revs increase when the clutch pedal is pressed even though I have lifted off the throttle. Usually results in me smashing gears and swearing a lot, very annoying.

Grounds for getting rid of a car very quickly.

MikeRJ - 22/4/08 at 10:00 AM

quote:
Originally posted by Alez
So now I don't know what to blame for the terrible throttle response that some cars have. I thought it would be the EFI in itself and I would have to live with carbbed cars forever because of this (I love them but they are not great for the environment).


EFI is not inherently like this, if it were then it wouldn't be used for performance applications (e.g. F1!).

The reason that modern euroboxes have that mushy, sluggish throttle response because it's deliberately engineered into the system. One reason is for refinement (i.e. Noise, Vibration and Harshness). By using softer engine mountings, transfer of vibration to the shell can be minimised, but makes the engine more prone to moving around. By slugging the throttle response this can be minimised.

Another reason is that emissions targets are getting very tough to meet. By using "fly by wire" throttles, the response to sudden throttle openings can be damped out, menaing that you don't need anything like as much fuel for acceleration enrichment which helps emissions and fuel economy.

I agree that driving these cars is an exercise in frustration, the engine is so unresponsive and lethargic that you'd swear there was something wrong with it if you didn't know better. I recently drove a new shaped Astra 1.6 SXi, and the performance (or rather lack of) was simply laughable, my old 1.1 Fiesta was quicker off the mark.

[Edited on 22/4/08 by MikeRJ]

Alez - 22/4/08 at 11:21 AM

Cheers, it all makes perfect sense now because the MX-5 is a '91 therefore emissions and fuel economy are not as restrictive. Also the cars I'm hating the most because of this effect are all very new (my brother's Golf mk4 is one example).

Thanks!

[Edited on 22/4/08 by Alez]

Alez - 22/4/08 at 11:47 AM

quote:
Originally posted by MikeRJI recently drove a new shaped Astra 1.6 SXi, and the performance (or rather lack of) was simply laughable, my old 1.1 Fiesta was quicker off the mark.


My first car ever was a 1.1 Fiesta mk1 which used contacts for ignition if I remember well. It didn't have much power but, being so simple, the little car was very light and actually very responsive and reasonably quick as a consequence.


[Edited on 22/4/08 by Alez]

mark chandler - 22/4/08 at 06:12 PM

I had the misfortune of hiring a 1.8 auto astra a few months ago, as you drew to a halt the gearbox disengaged and you jolted to a stop, when pulling away it span up then you felt the clutch bite and off you jerked..... all very poor.

Unfortunately it has to be said, get a proper jag none of that fluffy rubbish as tehy are meant to go fast!