Engine Management Light

Engine Management Light

Author
Discussion

Rotten Egg

Original Poster:

1,152 posts

247 months

Sunday 28th August 2011
quotequote all
I'm after some advise / experience please ladies and gents,

My Elise is an S2 'S' 2007 car with the Toyota lump totally standard apart from a 2Bular exhaust.

Occasionally the engine management light comes on and the car goes into a forced idle start where the engine revs itself between 1500 - 2500 rpm irrespective of throttle input.

This only seems to occur when the car has run hot - for example yesterday I got caught in a traffic jam on the A42, the temp rises, fans cut in and all appears fine.

I got to destination, stopped to get something out of the boot and when I restarted the engine the above occurs.

If I then wait 10 / 15 mins or so, the engine cools, turn the key and it runs fine - other than the MIL light is now on solid.

This morning, I jump in, fire up and all fine - MIL now not lit.

Twice, I've had the MIL read / reset by a local garage and so far the codes have pointed to a throttle body issue. Only yesterday did I realise that this only occurs after the fans etc have run from not moving.

Now I'm not convinced it's a throttle body issue but maye something else - What I don't know.

I know it's not related to the exhaust because it has happened both before and after changing the system.

Before I dive in and replace throttle body (££), does anyone have any experience of this problem and can you offer any advice ?

Thanks in advance,

Simon

McDuck

55 posts

207 months

Monday 29th August 2011
quotequote all
That sounds identical to the problem I had on my car - this is the description I wrote two months ago:


[i]I have a 2007 1ZZ Elise S, one of the early-ish DBW throttle cars. The car has a non-standard exhaust but does not have an induction kit.

Been having issues when the engine is hot and I restart it (e.g. after filling up with petrol). On restarting, it idles at 1,500-1,800rpm and goes into limp home mode, it won't rev past 2,000rpm, MIL on solid. It usually chucks up the Throttle Position Sensor fault code.

This only (occasionally) happens when the engine is hot, it never happens on a cold start.

If I leave the car to cool down for 15-20 mins, it will start up and run absolutely fine. The MIL light will disappear after a couple of restarts.

Having done some searching on here, I got a dealer to update the ECU software this morning - unfortunately, this has not fixed the issue.

Reading other people's experiences, the next step seems to be to replace the DBW throttle pedal unit - it sounds like some of the earlier units have iffy sensors.

Before I try this, does anyone have any other suggestions or experiences? The cost of the pedal unit ain't cheap and I'd like to sort this once and for all...[/i]


The problem got worse and worse, and the car did the self-revving thing which you mention. I eventually started getting MIL lights on random cold starts.

A Lotus dealer and a specialist both pulled the codes and acutlaly saw the fault - both recommended changing the drive-by-wire accelerator pedal, which would have cost £200-300. However, Paul at PSR Automotive was convinced the problem was the throttle body.

A brand new throttle body is £860 (eek!), however second hand ones are readily available from breakers for £150-200. Mine came from an Avensis which had done 6,000 and was less than a year old. Note, the 1ZZ used a cable throttle not DBW pre-2006 or pre-2007 (I can't remember), so make sure you get the right one. Labour to fit the TB shouldn't be much.

I've done more than 2,000 with the replacement throttle body, including a hot trackday at Le Mans this month - I haven't had a single reoccurance or MIL light at all. I am still using the original drive-by-wire accelerator pedal. I'm sure PSR would be happy to discuss - mention Chris' car.

Incidentally, I have heard of a few early Elise S' which have been suffering MIL light issues lately... these cars must be reaching that sort of age.

Rotten Egg

Original Poster:

1,152 posts

247 months

Tuesday 30th August 2011
quotequote all
McDuck said:
That sounds identical to the problem I had on my car - this is the description I wrote two months ago:


[i]I have a 2007 1ZZ Elise S, one of the early-ish DBW throttle cars. The car has a non-standard exhaust but does not have an induction kit.

Been having issues when the engine is hot and I restart it (e.g. after filling up with petrol). On restarting, it idles at 1,500-1,800rpm and goes into limp home mode, it won't rev past 2,000rpm, MIL on solid. It usually chucks up the Throttle Position Sensor fault code.

This only (occasionally) happens when the engine is hot, it never happens on a cold start.

If I leave the car to cool down for 15-20 mins, it will start up and run absolutely fine. The MIL light will disappear after a couple of restarts.

Having done some searching on here, I got a dealer to update the ECU software this morning - unfortunately, this has not fixed the issue.

Reading other people's experiences, the next step seems to be to replace the DBW throttle pedal unit - it sounds like some of the earlier units have iffy sensors.

Before I try this, does anyone have any other suggestions or experiences? The cost of the pedal unit ain't cheap and I'd like to sort this once and for all...[/i]


The problem got worse and worse, and the car did the self-revving thing which you mention. I eventually started getting MIL lights on random cold starts.

A Lotus dealer and a specialist both pulled the codes and acutlaly saw the fault - both recommended changing the drive-by-wire accelerator pedal, which would have cost £200-300. However, Paul at PSR Automotive was convinced the problem was the throttle body.

A brand new throttle body is £860 (eek!), however second hand ones are readily available from breakers for £150-200. Mine came from an Avensis which had done 6,000 and was less than a year old. Note, the 1ZZ used a cable throttle not DBW pre-2006 or pre-2007 (I can't remember), so make sure you get the right one. Labour to fit the TB shouldn't be much.

I've done more than 2,000 with the replacement throttle body, including a hot trackday at Le Mans this month - I haven't had a single reoccurance or MIL light at all. I am still using the original drive-by-wire accelerator pedal. I'm sure PSR would be happy to discuss - mention Chris' car.

Incidentally, I have heard of a few early Elise S' which have been suffering MIL light issues lately... these cars must be reaching that sort of age.
Chris,

Thanks very much for the feedback - sounds exactly the same !

I'll put a call to PSR and see where we go.

Will provide feedback.

Simon

david000

173 posts

221 months

Sunday 25th September 2016
quotequote all
My car had the same symptoms almost from new and in the end I replaced the throttle body off a random Toyota via ebay. We had to tweak one of the coolant pipes but otherwise all has been well for a couple of years.

Is it possible to rebuild \ fix the old bodies ?