high load cough

[theelanman]

Its an intermittent cough at high end load.......
Overtake something....4/5 coughs......throttle back......runs sweet as a nut....
Im thinking coil packs n leads........
If I get chance today ill try to get an elanscan run in

[Dave Eds]

bad case of catarrh judging by the state of my front bumper after you fired it up yesterday morning G!

[theelanman]

Took it for its MOT yesterday......gave it a foot down test.......
No cough........mmmmm.......looks like its intermittent as ive not had chance to do anything yet.......so do we reckon coil packs?.........

[Specky]

and...or mucky injectors.

TTFN

[theelanman]

Its back.....and now with cel......doh
Cough bang light backfire.....light out fine.....
Mmmmmm
I didnt get time to cheapscan it as I was rushin to get home to go out.....
Will try to get a code.....

Just read the mucky injector thread.....sounds like I might as well get em done.....

[John_W]

Gareth,
A bit prevoius as you haven't read the error codes yet, but have you replaced the HES?
John

[theelanman]

Yep twice.......
Altho the last one was about 2 months ago n its not really been anywhere since.......

[HJ2]

... and did you replace sparkplugs?

[theelanman]

Coils plugs and leads were my first choice.......
But hadnt got round to it.....
First time no cel so I would be guessing..
Now I have cel I should be able to detect problem a bit easier I hope

[carlotus]

Hi theelanman

I would start with easy tasks first. Change out the
spark plugs and the leads.

I had the same problem and changing the plugs and
leads cured my problem.

Good luck

Regards

Carl

[theelanman]

mmmmm.....
its back....
the strange thing is that Ive just serviced the car and put new plugs and leads in....(brand new magnecor)
Ive chucked the plugs but still have the old leads.....I think Im going to change back.....
also the oil pressure seems to be down a little.......about .5 bar down (4.5 under load.....2 at idle.....compared to 5 and 2.5 before....)
the turbo also seems a little sluggish.......seems to get to .5 bar then is reluctant to move further.....I know Ive got a stick wastegate and need to wiggle but would this stickiness still affect the boost at the bottom end...(I have only experienced it at the top end pop when the CEL comes on)
ta
G

[HJ2]

I asked about the plugs, because you'll have to make sure they are gapped to 0.8 mm!
Have you checked this?

[dapinky]

Can't offer any advice on the missfire (other than agreeing with Henk-Jan), but on the oil pressure, are you using the same oil since the service?

A thinner oil will give a slightly lower pressure......

....i noticed this on mine on Saturday - car got a tad warm on track and oil pressure dropped to a level that was worrying me a bit, but it picked up again once car had cooled down. Have now changed the 'old' oil (5W30 fully synthetic) for 15w40 'high milage semi synthetic' and have seen a nice improvement in pressure.

[hodge]

'the turbo also seems a little sluggish.......seems to get to .5 bar then is reluctant to move further.....I know Ive got a stick wastegate and need to wiggle but would this stickiness still affect the boost at the bottom end...(I have only experienced it at the top end pop when the CEL comes on)
ta
G

hi Gareth,
yes, wastegate stuck in closed position will give the 'top end pop and CEL light' (overboost) as you say but if it's stuck in open position it will vent (waste?) exhaust pressure away from the turbo so there is less to drive it, result - reduced turbo action (boost) , esp noticeable at low revs.

pete

[tigerdog]

If the car is boosting normally and coughing at high load, definitely check the plug gap. In installed NGKs gapped at 1.2 and had issues at full boost; dropping back to .8 cured it completely. I haven't used magnecors but if they are suspect, a number of us are using Kingsborne 8mm wires to good effect. They are relatively inexpensive, made in a variety of colours and if you mention Lotus Elan Central, they may still offer a discount because of the group buy we did a couple of years ago.

[lotuska]

I had a very similar issue a long time ago, check the following Link, and it doesn't cost anything to change.