free hit
counters
S4S - Engine/Ancilliaries - The Lotus Forums Jump to content
Sign in to follow this  
pytliks

S4S

Recommended Posts

hello, ..on warmup, idle is fine at about 1300rpm and drops automatically to about 1000, I am touching the throttle to bring it slowly up to 2000 then it breaks down, some backfire, maybe hits 2300 then drops off to about 1900 and its ok, cycles repeat like this...have run freescan, replaced Lambda O2 sensor, new fuel pump, new crank sensor....have some relays on order...

anyone close to me who could have a look, anyone had a similar problem ? Melton Mowbray, Leicestershire (midway between Leicester/Nottingham/Grantham/ Stamford....

thanks, paul

Share this post


Link to post
Share on other sites

Upgrade today to remove Google ads and support TLF.

had new plugs but must say will look at leads... but why so critical around 2000rpm? its perfect up till then...

Share this post


Link to post
Share on other sites

Have you changed the chip/memcal recently? Or how about the fuel filter (long shot)

Edited by fmxa

Paddle Faster, I hear Banjos!

Share this post


Link to post
Share on other sites

no chip changes...it seems strange to break down so specifically?..after its warmer, might get to 2300 but she's struggling and inevitably falls back to below 2000...

Share this post


Link to post
Share on other sites

How about the fuel filter?


Paddle Faster, I hear Banjos!

Share this post


Link to post
Share on other sites

The ECU has a 'get (limp) you home' mode when a serious fault occurs.

Not sure if it limits the revs this low, but one of our more tech people

(Dermot?) might be able to tell you if this is a possible cause of your

problem.

:D

Share this post


Link to post
Share on other sites
post-1009-1131875180.jpghi Paul, the freescan software showed following fault...have some relays on order from Lotus, should be here on tuesday, but will also get a fuel filter... have attached the reading....

Share this post


Link to post
Share on other sites

can eliminate fuel filter, as fitted new one, same result.... can anyone provide scenario, if say the timing belt had come out of synch, could you get this effect??...spark advance looks to be operating normally....

Share this post


Link to post
Share on other sites

Stick the most obvious:

You have a freescan log saying that there is a problem - this is the most likely source and I'd eliminate that before doing anything else.

Some cars have a a double contact relay for the fuel pump and the injectors and another for "ignition supplies (rear)" whatever that is! Both relays are part number A082M6182F.

I'd swap both of these out before doing anything else. If that clears the fault code and you still have the problem then you can look for a mechanical solution safe in the knowledge that the engine management is OK.

By the way, these are almost certainly standard relays - probably available from Halfwits / your local auto factor - no need to pay Lotus prices...


Ian

Share this post


Link to post
Share on other sites
hi Jens...new fuel pump fitted recently...

<{POST_SNAPBACK}>

How's the TPS reading?

Is it possible the over run fuel cut off is acting up? That is, above a certain rpm and below a certain TPS (often 2%), the ECU will cut the injector signal on the overrun to reduce fule consumption and emissions. Injection is resumed around 1400 rpm or so.

I'm guessing that something is causing the ECU to shut off the injectors incorrectly. Could be an incorrect TPS reading or calibration.

No DTC's?

Michael

Share this post


Link to post
Share on other sites

well guys...GOOD NEWS...had an email from Lotus Technical Dept this morning '' Try reversing the two cables on the engine speed sensor'' (had a new one fitted 12 months ago) and had this problem allied to a couple of other items, since then...am advised a manufacturing fault had occurred but Lotus did not do a recall or advise buyers!!!!!...to say i'm pissed off with the factory is putting it very mildly !!!!!!...i'm livid....but happy that engine revs to over 5500 with no difficulty !!!!...thanks all,,,

Share this post


Link to post
Share on other sites

Hi,

Is the EBPV (= Exhaust Back Pressure Valve) operating properly ???

Maybe its stuck close ... ?

Marcus


Marcus

Share this post


Link to post
Share on other sites

sorry, its Paula and Marcus... anyway have written to Lotus CEO about the poor quality control of parts supplied, 6 weeks ago also had to exchange a defective new fuel pump...wrongly wired up at manufacture, engine speed sensor, hope the new timing belt is ok??.... <_<

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Sign in to follow this  

×
×
  • Create New...