Boost - overboost, newbie question

[Benmac]

Hi all,

Been wanting an Elan for a while (see my hello post in the general section).

Anyway, got a nice car from WillB who I know from Seloc and plan to spend some time doing some mild restoration. Nothing much just tidying up. Anyway, on the way home I struck a little bit of an issue.

Will thinks its overboost and having had a quick look now I think that may be the case but I thought I'd ask the question for some specific help. Any guidance, pics, how tos gratefully received.

Basically when you really gun it the boost quickly goes up to nearly 1 on the gauge! That seems a touch high! The issue was that it did this when accelerating hard and the engine behaved as if it had misfired or hit a limiter momentarily and the MIL light came on. Backed off and coasted and the light went off and all was well. Doesn't do it every time and you can happily drive round it by not going mad but it would be good to fix it. Car feels utterly fine otherwise, nice and smooth, gauges where they should be etc etc.

Will and I think it may be chipped as it certainly feels very strong. I know the ECU is behind the glovebox. What would I see if that is the case? I'd happily revert to standard if it is chipped and this is the issue (basic chip just winding the boost up??) and maybe invest in an Everest later on.

[Enright]

I'd say you have one of two problems:
Either you have a big bore exhaust and the wastegate can't keep up with the increased flow, or the wastegate is just sticking.

If it's the former then one of Alan's chips might help because of it's programming, but the only real solution is to port the wastegate, which is quite an in depth job on a 15 year old car with lots of rusted fasteners (believe me, I know)!

If it's the latter then you need nothing more than a set of molegrips.
You just look for the wastegate actuator rod below the front of the turbo heat shield, and wiggle the bejesus out of it from right to left. That will nicely free it up and then it shouldn't overboost.

Oh, and to tell if it's been chipped, have a look to see if the security seals on the ECU have been broken. If they have, then it's a fair bet that someone's put something a bit fruitier inside!

Edit: I found a pic from when I took my turbo off to port the wastegate, which clearly shows the actuator rod at the bottom:

[Benmac]

Cool, thanks, I'll have a wiggle and see how I get on. Its got some sort of stainless exhaust which sounds decent enough, but I haven't had a chance yet to poke around to see if its a particularly big bore.

I do hope its the former. Will just drive round the issue for now. When you say 'port' do you mean proper grinding out by a pro or is it something I could do with my dremel?

[Benmac]

Just had a look and I've found the actuator rod. Saw that I'll need to take the heat shield off to do it so as a precaution I whacked some penetrating oil on the bolts for that!

Wish me luck, I do hope its that.

Had a look at the ECU quickly. Haven't taken it out so dunno about seals. Odd one though to the right of the ECU a little bit behind it there was a dangling connector and nearby a socket that pointed up that seems just right for the connector. I'll take a pic but in the meantime any ideas? I've left it unplugged for now as that's how I found it.

[GeoffSmith]

Welcome Ben.

It sounds like your boost creep is caused by the exhaust (a few of us suffered after getting a 2¼" Peco exhaust). Porting the wastegate is a DIY job and Neil did a write up with pictures I seem to remember. It's one of my jobs for the Winter (maybe) but you soon get used to easing off when neceesary, to avoid it.

I'll be interested to hear how the Elan/Elise comparisons go - they were my two top options at the beginning of the year and I chose the Elan (after a chat with Will).

Geoff

[Monty]

Hey Ben,

Not much to add to what the lads have already said, but noticed u`r a member of NORLOG are u living up in the NW? Do you go to there meets? as i could meet up and have a chat.

[Dico]

i could meet up and have a chat.

And see if you have a BBR kit fitted rather than an ecu chip??

[GeoffSmith]

Don't forget it's one of Will's. Wouldn't he recognise a BBR or MBC?

[WillB]

Don't forget it's one of Will's. Wouldn't he recognise a BBR or MBC?

I must admit I'm not too hot on the differences as I think most if not all of my previous Elans have been pretty much standard.

Ben's Elan is the 1st I've ever driven with the Wilwood brake upgrade! I've done about 1000 miles in his Elan and didn't get the boost creap. I guess I must be getting slow in my old age and never took advantage of full boost!

I remember viewing one last year on which the owner said it had a BBR kit and the engine bay wiring was in a bit of a mess.

Am I right in remembering that Dico's Elan has the BBR kit?

[Enright]

Just had a look and I've found the actuator rod. Saw that I'll need to take the heat shield off to do it so as a precaution I whacked some penetrating oil on the bolts for that!

Wish me luck, I do hope its that.

Had a look at the ECU quickly. Haven't taken it out so dunno about seals. Odd one though to the right of the ECU a little bit behind it there was a dangling connector and nearby a socket that pointed up that seems just right for the connector. I'll take a pic but in the meantime any ideas? I've left it unplugged for now as that's how I found it.

You really shouldn't need to remove any heatshields to free up that actuator rod. It's tricky (expect skinned knuckles) but doable - if you try to undo the bolts they'll probably snap, and give you hardly any extra access.

The plug sounds like the ALDL link, and the socket is a blank which is just the retainer for it.

Oh, and if you read from here onwards, you'll see my porting wastegate story.

[Sy V]

Ben

Everything that Neil (Enright) has suggested thus far is spot on. I'll just embelish it a bit.
Original diameter of OEM exhaust is 2" even 2.25" aftermarket exhausts can cause your symptoms.
The wastegate actuator rod wiggling exercise is best performed from underneath, especially if (like me) you have fingers more comparable with pig's tits!

[Enright]

Sy is also spot on in his embellishment - he does have fingers like pig's tits!

[GeoffSmith]

Some useful info on the ECU is here. The fingers holding the MEMCAL are obviously not Sy's.

[Monty]

don`t think it will be a BBR as it sounds like Ben is hitting the fuel cut

If it has the wilwood kit, who was the previos owner? got to be someone of here and would bet it`s chipped and aftermarket exhaust.

[Benmac]

Cheers, chaps, all good stuff I'll do some reading. Had a proper waggle of the actuator rod so we'll see if that helps. Haven't driven it since. Porting looks doable given my skills and tools so will plan to do that to at some point.

Exhaust is definitely aftermarket but I haven't been right under to check the bore. Symptoms when its done it defintiely sounds like the fuel cutout, had a quick read of the manual.

Took it to a Norlog meet today with the wife behind in the Elise (yes Monty I actually had a good nose at your car at Phoenix on their open day)

Swapped cars on the return and the Elise threw a minor wobbly. It had a sticking stat a couple of months back and it seemed to do it again then came back to life. Hmmm.

Then I got home and gave the Elan a really good wash to prep for polishing and had a proper poke about looking for jobs to add to my list pf things to tidy up. Then locked the keys in the boot. Arrrrggggh. AA out and we quickly got it open but then it took an eternity to put the barrel back in. We ended up taking the boot lid off to do it as gravity was against us.